11-30-20 DeepMind's AI biologist can decipher secrets of the machinery of life
An AI system developed by UK-based company DeepMind has achieved the long-sought-after goal of accurately predicting the shape of proteins from their sequence alone, a key part of understanding how the machinery of life works. In a competition, AlphaFold was able to match two-thirds of the results achieved by humans doing expensive and time-consuming lab experiments. “I was really wowed when I saw it,” says John Moult at the University of Maryland, one of the competition’s organisers. “This is the first time we’ve come close to approaching experimental usefulness, which is pretty extraordinary.” Proteins are vital for life. Cells are full of machines – from turbines that generate energy to transporters that walk along tracks pulling cargo – that are built from proteins, and the shapes of these machines are crucial. For instance, the coronavirus can enter and infect cells because the spike protein on its surface fits into a receptor on human cells, like a key into a lock. These shapes depend on the sequence of 20 different amino acids that are chained together to make proteins. It is easy to work out the sequence of any protein because this is determined by the DNA that codes for it. But despite half a century of efforts, biologists hadn’t previously been able to work out the shape of a protein from its sequence alone. Instead, they have had to rely on experimental methods such as X-ray crystallography, which involves analysing the diffraction pattern formed when an X-ray beam is fired through a protein crystal. “This is exceptionally difficult,” says John Jumper, who leads the AlphaFold team at DeepMind. Making crystals of some proteins is hard, and interpreting the diffraction patterns can be tricky. Brute-force computing based on physics alone isn’t an option, because proteins are too complex. Instead many groups worldwide have turned to machine learning, where AI systems are trained using data sets of known protein structures.
11-30-20 Coronavirus: How do you vaccinate 7.7 billion people?
What happens once a coronavirus vaccine is approved? Kalipso Chalkidou, director of global health policy at the Center for Global Development and Nicole Hassoun, an ethicist at Binghamton University in the US, discuss five challenges we'll need to overcome to vaccinate billions of people around the world.
11-30-20 Covid vaccine: Moderna seeks approval in US and Europe
Moderna is filing for US and European emergency regulatory approval of its coronavirus vaccine so that it can be recommended for widespread use. Regulators will look at trial data for the mRNA vaccine and decide if it is safe and effective enough to recommend for roll out. Clinical studies show the jab is more than 94% effective at protecting people from becoming ill with Covid-19. Pfizer, which has a similar jab, has already filed for the same US approval. UK regulators are also reviewing data on the Pfizer vaccine, as well as another type of Covid vaccine from AstraZenca and Oxford University for emergency approval. Moderna says it hopes to gain UK approval soon, now that it has trial data from 30,000 volunteers - including high risk groups like the elderly - that suggests it works. In those studies, 15,000 people received the real vaccine while the other participants got placebo injections. No serious side effects were reported. During the studies, 185 people in the placebo group fell ill with Covid-19, and some severely so. In comparison, there were 11 cases in the vaccine group and none were severe. Full trial data has not been released, but will be published in a peer-reviewed journal in due course. The three front-runner vaccines have different pros and cons. The AstraZeneca jab is cheaper - around £3 ($4) for a dose, compared to around £15 ($20) for the Pfizer vaccine and £25 ($33) for Moderna's. And it is potentially easier to distribute because it does not need to be stored under ultra-low temperatures. But its efficacy in trials - between 62% and 90% - is a bit lower than the Pfizer and Moderna vaccines. Dr Alexander Edwards, associate professor in biomedical technology at the University of Reading, said: "This is great news indeed - the more trial data that we have, the greater confidence we have that vaccines can be used to blunt the human cost of Covid-19.
11-30-20 One of biology's biggest mysteries 'largely solved' by AI
One of biology's biggest mysteries has been solved using artificial intelligence, experts have announced. Predicting how a protein folds into a unique three-dimensional shape has puzzled scientists for half a century. London-based AI lab, DeepMind, has largely cracked the problem, say the organisers of a scientific challenge. Their program determined the shape of proteins at a level of accuracy comparable to expensive and time-consuming lab methods, they say. The discovery is expected to accelerate research into a host of diseases, including Covid-19. Dr Andriy Kryshtafovych, of University of California (UC), Davis in the US, one of the panel of scientific adjudicators, described the achievement as "truly remarkable". "Being able to investigate the shape of proteins quickly and accurately has the potential to revolutionise life sciences," he said. Proteins are present in all living things where they play a central role in the chemical processes essential for life. Made up of strings of amino acids, they fold up in an infinite number of ways into elaborate shapes that hold the key to how they carry out their vital functions. Many diseases are linked to the roles of proteins in catalysing chemical reactions (enzymes), fighting disease (antibodies) or acting as chemical messengers (hormones such as insulin). "Even tiny rearrangements of these vital molecules can have catastrophic effects on our health, so one of the most efficient ways to understand disease and find new treatments is to study the proteins involved," said Dr John Moult of the University of Maryland, US, the chair of the panel of scientific adjudicators. "There are tens of thousands of human proteins and many billions in other species, including bacteria and viruses, but working out the shape of just one requires expensive equipment and can take years."
11-29-20 The vaccine breakthrough
Pfizer and Moderna may soon begin emergency distribution of coronavirus vaccines created with genetic technology. Pfizer and Moderna may soon begin emergency distribution of coronavirus vaccines created with genetic technology. Here's everything you need to know:
- How do these vaccines work? Up to now, vaccines have introduced the immune system to a benign version of a virus or bacteria, priming it to recognize and fight the real pathogen if and when it strikes. Vaccines for measles, polio, the flu, and other infectious diseases use parts of or entire viruses that have been weakened or inactivated. The Pfizer and Moderna vaccines are based on a novel approach. They rely on a snippet of genetic material called messenger RNA, or mRNA, that is encased in a tiny, protective bubble of fat.
- What does messenger RNA do? When the coronavirus attacks, it hijacks the machinery of our body's cells and instructs them to crank out more virus, generating a cascading assault. The vaccines take advantage of this process by injecting mRNA into muscle cells in the upper arm, which are instructed to manufacture just a piece of the coronavirus — the outside spike proteins, which the virus uses to latch onto cells.
- How well do these vaccines work? Phenomenally well, so far. The benchmark for FDA approval is an efficacy rate of 50 percent, roughly the average of what flu vaccines achieve. Early results for the Pfizer and Moderna vaccines show about 95 percent efficacy, including for those over 65 — a game-changing result.
- Are there any drawbacks?: The downside of messenger RNA is its fragility, which leads to significant practical hurdles. To keep from degrading, Pfizer's vaccine must be stored at minus 94 degrees Fahrenheit, roughly the winter temperature of the South Pole.
- What about safety? So far, the only side effects that have been reported by some recipients are fatigue, fever, joint pain, headaches, and soreness in the injection site lasting a day or two. Close monitoring of the study subjects will continue, but adverse vaccine effects typically surface early.
- When can I get one? Both companies have manufactured tens of millions of doses and are ready to hit the ground running when approval is granted. Still, mass inoculation will take at least four to six months.
- The enormous promise of mRNA: The excitement over mRNA vaccines' early success extends well beyond what it means for the coronavirus pandemic. The trial data offer the first solid evidence for a technology whose potential has excited researchers for years, and hold out great promise for the fight against other diseases.
11-28-20 What the coronavirus vaccine shows about the potential for innovation
Money and hard work gets the goods. The word "innovation" is now one of the most cursed in the English language. Silicon Valley robber barons recognized the cultural capital created by millions of inventors and scientists going back thousands of years, and colonized it to describe their ruthless business practices or semi-pointless new widgets. Innovation used to mean things like "developing new crop varieties that feed a billion people," now it means "creating a new way to trick people with compulsive personalities into spending $10,000 on Mobile Clans Fun Bucks." Nevertheless, it would be a mistake to cede the word entirely to Elizabeth Holmes or Mark Zuckerberg. Because the last several months have seen one of the most astounding examples of innovation in human history: the development of not one, not two, but now three different coronavirus vaccines. Thus far a Pfizer/BioNTech project, one from Moderna, and another from AstraZeneca/Oxford University all look good and will ideally start being distributed within weeks — and there are dozens more possibilities already in trials behind them. It turns out human society can achieve a lot if we just try really hard. Who knew? The speed of this vaccine development is totally unprecedented. Previous vaccines have taken years at best and usually over a decade to be developed and proved to work. Now, scientists did have some advantages in this case, as the SARS-CoV-2 virus seems to be relatively easy to target with a vaccine, and there are (alas) a whole lot of infections happening, which makes gathering the necessary data on efficacy easier. And the various scientific teams have built on years of past work developing a basic format for messenger RNA vaccines, which is what the first two vaccines use. But on the other hand, science was also starting from scratch. Unlike chicken pox or measles, which had been studied for decades before work on a vaccine started, scientists had to figure out how the virus works from a standing start — by sequencing its genetic code, analyzing its proteins, and so on — before getting to work on a vaccine. Yet all three were still designed and completed within a few months. It seems what happened is that governments and private companies hurled massive quantities of resources and manpower at the problem. The European Union, desperate for a way to throttle the pandemic, directed billions in grants, contracts, and purchase orders as a promised reward. Even the Trump administration also pitched in several billion dollars in similar fashion with Operation Warp Speed. Then pharmaceutical companies found that their profit incentive lined up neatly with the need for a vaccine. Whoever could develop one and prove it worked fastest would reap enormous profits — and even the laggards would probably get a piece of the action too, since it will not be possible to produce any one vaccine fast enough to get it to the entire planet. So all the big players got their top scientists working around the clock. There are a lot of ways innovation can happen, from the private tinkerers at Bell Labs to the fully government-run Manhattan Project to good old academic science. But major, rapid breakthroughs tend to happen just like this — when large available resources and expertise coincide with the kind of intense social pressure that focuses the mind and leads people to put forth their maximum effort.
11-27-20 Oxford/AstraZeneca Covid vaccine 'dose error' explained
On Monday, the world heard how the UK's Covid vaccine - from AstraZeneca and Oxford University - was highly effective in advanced trials. It gave hope of another new jab to fight the pandemic that should be cheaper and easier to distribute than the Pfizer/BioNTech and Moderna mRNA vaccines that announced similarly impressive results just days before. But after the jubilation, some negative press has followed. On Thursday, multiple news outlets in the UK and US reported that there were questions over the data. They weren't about safety, but rather how effective the jab is. The questions centre around efficacy levels. Three were reported from the trial - an overall efficacy of 70%, a lower one of 62% and a high of 90%. That's because different doses of the vaccine were mistakenly used in the trial. Some volunteers were given shots half the planned strength, in error. Yet that "wrong" dose turned out to be a winner. Some of the shots were weaker than they were designed to be, containing much less of the ingredient that is meant to give a person immunity. The jab is actually two shots, with the second given a month after the first as a booster. While most of the volunteers in the trial got the correct dose for both of their two shots, some didn't. Regulators were told about the error early on and they agreed that the trial could continue and more volunteers could be immunised. The error had no effect on vaccine safety. About 3,000 participants were given the half dose and then a full dose four weeks later, and this regime appeared to provide the most protection or efficacy in the trial - around 90%. In the larger group of nearly 9,000 volunteers, who were given two full doses also four weeks apart, efficacy was 62%. AstraZeneca reported these percentages and also said that its vaccine was, on average, 70% effective at preventing Covid-19 illness. The figures left some experts scratching their head.
11-27-20 Do Oxford/AstraZeneca covid-19 vaccine results stand up to scrutiny?
Earlier this week, pharmaceutical giant AstraZeneca and the University of Oxford released positive results about their covid-19 vaccine, claiming that it was on average 70 per cent effective, and could reach 90 per cent efficacy depending on dosing. But now, several questions have been raised over the findings. What’s going on? As scientists, journalists and business analysts chewed over the figures, they noticed some potential problems with the way the trial was conducted, which cast some doubt on the reported results and could be a hindrance to getting the vaccine approved. In a word, methodological. “There are lots of issues,” Paul Hunter, professor in medicine and expert on clinical trial methodology at the University of East Anglia, UK, told New Scientist. Rather than results from one large phase 3 trial, which is what we saw from trials of other covid-19 vaccines, these results were actually pooled data from two separate trials, one in the UK and the other in Brazil. And there was a glaring mistake in the way one of the two trials was conducted. Due to a laboratory error, some of the participants in the UK-based trial got roughly half of the intended dose of their first shot (the vaccine requires two shots at least a month apart). The error violated the protocol setting out how the trial was supposed to be conducted, but the trial continued and the data from those volunteers was included in the analysis. According to a report in the New York Times, the vaccine developers noticed the error – which was the result of work by a third-party contractor – while the trial was ongoing, but consulted with regulators and were given the go-ahead to press on. Yes. The volunteers who received the erroneous half-dose first shot turned out to have a higher level of protection against covid-19 than those who did not. The “full dose” vaccine was 62 per cent effective but the half dose 90 per cent. That is the source of the 70 per cent average and the notion that the vaccine might be tweaked to hit 90 per cent.
11-27-20 We seem to find larger animals more charismatic than small ones
Humans seem to find larger animals more charismatic than smaller ones – although some exceptionally small species punch above their weight when it comes to charisma. There are several recognised kinds of animal charisma: aesthetic – the innate human response to how an animal appears; ecological – how notable an animal is based on the likelihood that it will be encountered by humans; and corporeal – the emotions inspired by an animal in groups of people with lived experience of the species. There already exist a number of datasets that have measured animal charisma. Some involved surveying volunteers about their attitude towards particular species of birds and mammals, others involve assessing data on the number of Wikipedia page views for a particular species, and the number of images of the species posted to Twitter and the photo-sharing site Flickr. Emilio Berti – formerly at Aarhus University in Denmark – and his colleagues pooled together the information from nine of these existing datasets. This allowed them to assess the charisma of 13,680 animal species – including amphibians, birds, mammals and reptiles. The researchers came up with a standardised measure of charisma between 0 and 1 for each species based on their rankings within the respective datasets. Having completed the analysis. Berti and his colleagues found there was a correlation between charisma ratings and animal size – which was measured as the average adult body size for birds and mammals, and the maximum adult body mass for amphibians and reptiles. “The bigger you get, the more sublime reaction humans have,” says Berti. However, the researchers also found that a few of the smallest species also had a very high charisma rating. These included the Virgin Islands dwarf gecko (Sphaerodactylus parthenopion), which is one of the smallest terrestrial vertebrates at 18mm long. Berti says that extremely small species may also evoke strong positive reactions in people, potentially as a result of their perceived cuteness.
11-27-20 Thailand: Rare whale skeleton discovered
An almost perfectly preserved whale skeleton thought to be between 3,000 and 5,000 years old has been discovered in Thailand. The bones were found in early November some 12km (7.5 miles) off the coast just to the west of Bangkok. The 12m (39ft) long skeleton is thought to be that of a Bryde's whale. Experts hope the find might provide "a window into the past," especially for research on sea levels and biodiversity. The partially fossilised bones are "a rare find," mammal researcher Marcus Chua of the National University of Singapore told the BBC. "There are few whale subfossils in Asia," he said, and even fewer ones are "in such good condition". Pictures shared by Thailand's environment minister Varawut Silpa-archa show the bones apparently almost entirely intact. According to the politician, more than 80% of the skeleton has so far been recovered, including vertebrae, ribs, fins and one shoulder blade. The skeleton's head alone is estimated to be about 3m in length. Mr Chua says the discovery will allow researchers to find out more about the particular species in the past, whether there were any differences compared to today's Bryde's whales. The skeleton will also provide information about the "paleobiological and geological conditions at that time, including sea level estimation, types of sediments, and the contemporary biological communities at that time". "So this find provides a window into the past once the skeleton has been dated," Mr Chua says. The bones are yet to be carbon-dated to determine their exact age, with the results expected in December. The gulf of Thailand has an interesting history in the last 10,000 years, the biologist points out, with sea levels possibly up to 4m higher than today and active tectonic activity. The skeleton was found off the current coastline in Samut Sakhon. Bryde's whales, which live worldwide in warm temperate and tropical waters, are still found in the waters around Thailand today.
11-26-20 CRISPR gene editing of brain cells might prevent Alzheimer's disease
It might one day be possible to gene-edit brain cells to prevent Alzheimer’s disease. Researchers have discovered that altering a key gene in human nerve cells reduces the formation of a protein associated with the disease, though so far this has only been done in a dish. Alzheimer’s is the main cause of dementia and the risk rises sharply as we grow old. Around 1 in 4 people aged over 90 have it. The cause of Alzheimer’s still isn’t fully understood, but the leading hypothesis is that a build-up of clumps of a protein called beta-amyloid outside cells is to blame. Beta-amyloid forms when another protein, the amyloid precursor, is cut by an enzyme called beta-secretase. In 2012, researchers found that a few people of Scandinavian ancestry have a gene variant called A673T that makes them four times less likely to get Alzheimer’s. “You are not only protected from Alzheimer’s, you have a tendency to live longer,” says Jacques Tremblay at Laval University in Canada. “There is no downside.” Many variants of the gene for the amyloid precursor protein increase the risk of Alzheimer’s. But the A673T variant, which involves a change in a single DNA letter, instead reduces beta-amyloid production by altering the site to which the beta-secretase enzyme binds. It also makes the resulting beta-amyloid less likely to clump together. The A673T variant is found in roughly 1 in 150 people in Scandinavia, but is rare elsewhere. Because its benefits kick in very late in life, it isn’t selected for by evolution, says Tremblay, meaning the variant doesn’t spread. Engineering the variant into people’s brain cells could have many of the same benefits as inheriting it, he believes. His team has taken the first step to proving that by showing that beta-amyloid production is reduced when this change is made in human cells growing in a culture dish.
11-26-20 Coronavirus shutdowns don’t need to be all or nothing
Targeted restrictions can minimize economic harm and save lives if enacted early. We were warned this might happen. While millions stayed home last spring, looking to summer for respite from the virus, experts worried that an even larger fall surge was around the corner. We’ve rounded that corner. As cases and hospitalizations reach record levels across Europe and the United States, leaders are being forced to make hard decisions about what to shut down and when. In the United States, President-elect Joe Biden has made clear that he won’t call for a national lockdown, but more targeted shutdowns at the state or local level are on the table. And in fact, many regions are already rolling out more targeted approaches, focusing on crowded spaces like restaurants, bars, or schools. European countries began rolling out new restrictions in October, and in the United States many governors and city officials are beginning to partially clamp down. Public schools in New York City were closed on November 19; Minnesota has shuttered bars and restaurants for a month starting November 20; California officials enacted curfews between 10 p.m. and 5 a.m. in certain counties through December 21. Whether these fine-tuned restrictions will work remains to be seen. But scientists have been studying what worked and what didn’t in the early months of the pandemic, revealing some promising approaches. New research suggests that focusing on closing or reducing capacity at transmission hot spots while keeping less risky parts of the economy open can curb exponential rises in cases, while minimizing harm to the economy. “We don’t need to fully shelter in place to slow transmission,” says Lauren Ancel Meyers, a mathematical biologist at the University of Texas at Austin. But these sharper approaches work only if governments set clear guidelines and people follow them, she says. Even the smartest interventions will be overwhelmed if enacted too late amidst rampant transmission within a community.
11-25-20 The race to find and stop viruses that could cause the next pandemic
The coronavirus pandemic is still raging, but the clock is ticking towards the next big virus threat – can we track it down before it makes the leap from animals to humans? LURKING in the air, water, soil and inside every other living creature, viruses have us surrounded and hopelessly outnumbered. For every star in the known universe, there are at least 10 million viruses on Earth. They are so small that more than 100 million can fit on a pinhead. As 2020 has shown, just one of these is enough to bring society to its knees. The covid-19 pandemic offers a grim demonstration of how hard it can be to stop a new infection once it takes hold in the human population. But what if we could hunt down the next pandemic-causing virus before it starts spreading? If surveillance of viruses evolving in animals could identify the likely candidates, then we might be able to pinpoint the all-important leap they could make into humans. And by identifying the animal species carrying the most problematic viruses, measures could be put in place to prevent their spread. This kind of viral detective hunt is a Herculean endeavour, even before you add the difficulty of predicting which candidate out of millions will go on to infect us. Critics argue that it is impossible to stop the occasional rogue virus from jumping into humans and that we should instead focus on stamping out those infections when they occur. The debate has split scientists, but it needs to be resolved soon. Even as we continue to battle covid-19, the clock is ticking down towards the next outbreak of a novel pathogen. The health of humans, wildlife and ecosystems is intimately connected. As our population grows, more people live in contact with wild and domestic animals and so the odds rise that “zoonotic” pathogens will spill over species barriers to infect us. Yet even if new viral pandemics that spread from animals are inevitable, they are also staggeringly unlikely events. Fate and biology must combine in a precise way to put the wrong virus in the wrong place at the wrong time. First, a virus circulating in an animal must pose a threat to humans. Most don’t. They lack one or more of the bits of molecular machinery needed to bind onto human cells, replicate once inside and then spread further to other cells and other people – all without being mopped up by the immune system. Next, the animal harbouring a potentially dangerous virus has to come into contact with a susceptible person and shed enough infectious material near them to pose a threat. Lastly, the person needs to be infected by the virus somehow and be in sufficient contact with others to spread it.
11-25-20 Can mass testing schemes stop the spread of the coronavirus?
IT LOOKS likely that some countries will soon be able to vaccinate at least some people against the coronavirus, but until vaccines are widely available, mass testing is seen as a route back to normal life. For example, UK prime minister Boris Johnson announced on 23 November that daily coronavirus tests will be given to people who have come into contact with anyone who has tested positive for the coronavirus, in an attempt to limit the number of days they have to self-isolate. The measure will be trialled in Liverpool, which began mass testing earlier this month. But while extensive testing has helped places such as China and Singapore keep the spread of coronavirus low, it won’t work on its own. Many other policies are needed to make testing successful at containing the spread of the coronavirus. “Just testing people does not get rid of covid,” says Christina Pagel at University College London (UCL). People need incentives to get tested, for example, and it must be easy for them to do so. Those who test positive need to self-isolate, and they need financial support to do so. Their contacts need to be quickly traced, isolated and tested too. Once a region has eliminated the spread of coronavirus within a community, strict border controls can prevent it entering again from outside the region. And all this needs to be combined with wider measures to limit exposure, such as wearing face coverings and social distancing. “All those things have to work and if they don’t work, if one of them is leaky, you get problems,” says Pagel. “That’s what’s been happening in Europe.” This is why some researchers think the UK government is making a mistake in rushing to do mass testing without rigorously implementing these other measures. “The way [England is] going about it means it will fail miserably,” says Angela Raffle at the University of Bristol in the UK. Countries cannot simply pin all their hopes on vaccination and ignore testing, as it could take years to vaccinate entire populations. “We have a long process before we can roll out the vaccine,” says Jasmina Panovska-Griffiths, who is also at UCL. “[England] still needs to get test and trace right.”
11-25-20 Fears about genetically modified foods are cultural not scientific
Many people strongly object to genetically modified plants, but foods like sweet potatoes and grapefruits are a reminder that that these concerns are cultural rather than based on science, says James Wong. I HAVE always been fascinated by people’s cultural relationship with plants. You might assume understanding this is all about voyaging up the Amazon river to learn how indigenous peoples use traditional medicines, but, to me, the most interesting cultural beliefs lie much closer to home. Nowhere is this more the case than when it comes to the contentious issue of genetically modified crops. Yet it might surprise you to know that my concern is exclusively cultural, not scientific. One of the most intriguing things about culture is that it is such an intrinsic part of how we see the world. It can seem like culture is something only other people have, as within any given culture, its unique biases and preconceptions are largely invisible to those who share them. So it is unsurprising that many people with a cultural aversion to genetic modification are unaware that this is what it is. Many may be convinced that these are valid scientific concerns, reflecting the evidence. To illustrate that this an illusion, all you have to do is look at a few examples. With so many everyday crops now developed using GM techniques, many argue that choosing organic is the only way to avoid the practice in some countries. On this point, they would be right, but here is where the argument gets tricky. I bought some lovely Star Ruby grapefruit at an organic store the other day. Some may consider these to be perfectly natural, unless, of course, you know about their actual history. Star Ruby grapefruits are based on a genetic mutation generated by exposing plant material to atomic radiation. Known as radiation mutagenesis, this is a common breeding technique first developed in the 20th century that aimed to create all sorts of novel crop traits, using everything from cobalt-60 released in bursts from underground concrete bunkers in fields to simply strapping seeds to the insides of hospital X-ray machines. The potentially hundreds of mutations created were entirely random and unpredictable, and we have been able to identify only some of them. Everything from a cultivar of mint used to make menthol to a barley variety used to make beer were created through this technique and it is still in active use today.
11-25-20 The fluid in between your cells could help reveal health problems
The fluid between our cells could be used to diagnose and monitor health conditions. A patch made of tiny needles can sample this liquid and could be easier to use and less invasive than normal blood tests. Interstitial fluid, also known as tissue fluid, is the liquid that surrounds our cells. It leaks out of our blood vessels and into our body’s cells to deliver essential nutrients, while simultaneously removing waste products. “The fluid that fills the spaces between cells in tissues makes up almost a quarter of our bodily fluids,” says Mark Prausnitz at the Georgia Institute of Technology. He and his colleagues developed a patch made of five stainless steel microneedles that can create small punctures in a person’s skin. They tested the patch on 21 people by using it to take small amounts of interstitial fluid out of the body and comparing it with blood samples. The researchers found similar levels of important compounds in both samples, including glucose, caffeine and vitamin D. They say this means the approach could be used to test for these compounds and diagnose health problems related to their levels, such as diabetes. As the needles in the patch are much smaller than normal ones, the skin can heal from the punctures within a day. Previous methods used to draw interstitial fluid out of the body struggle with contamination from blood. To combat this, Prausnitz and his team gently ramped up the suction pressure used by the patch to ensure no nearby blood vessels were ruptured. “[This approach] may be more acceptable than blood tests – especially in paediatric medicine,” says Timothy Miles Rawson at Imperial College London. It could also be used for continuous monitoring of various compounds in the body, as interstitial fluid doesn’t clot, he says.
11-25-20 Tiny toucan-like bird with a single tooth flew during the dinosaur era
A bizarre bird from the Mesozoic Era had a small, scythe-like beak with one tooth at its tip. Its fossil was found in Madagascar and hints at a lost world of ancient birds that paleontologists are only just starting to uncover. Measuring less than 9 centimetres and sporting a curved, deep bill, the bird would have looked a bit like a tiny toucan. “When I first saw a photo of the skull, I thought I was looking at a modern-day toucan that was somehow encased in concrete,” says Steven Brusatte at the University of Edinburgh in the UK, who wasn’t involved in the study of the fossil. The skull of this bird, called Falcatakely forsterae, was preserved in rock between 66 and 72 million years ago. The fossil was discovered in a block of stone quarried out of a rich fossil spot in Madagascar. In addition to some big dinosaur bones, the quarry where Falcatakely was found also yielded some small bird bones, says Patrick O’Connor at Ohio University. He and his team wrapped the block in plaster for later study. When it was CT-scanned at the lab, the researchers saw a skull unlike any found before. Most prehistoric birds, like their modern counterparts, were small and had delicate, hollow bones. The harshness of the fossilisation process destroyed more ancient birds than preserved them. Yet when conditions were just right, exceptional specimens like Falcatakely were locked in stone. The fossil is paper-thin in places, but the beak, parts of the upper jaw and eye socket were preserved well enough to provide a detailed look at the bird’s profile. The bones mark Falcatakely as belonging to an extinct group of birds called enantiornithines that thrived during the Cretaceous Period. When the bird was alive, Falcatakely shared its relatively dry habitat with herbivorous, pig-like crocodiles, carnivorous, stubby-armed dinosaurs and badger-sized mammals. Falcatakely fits that oddball menagerie, the weirdness of which was probably spurred by Madagascar’s isolation after the island split off from India 88 million years ago.
11-25-20 The FDA has approved the first drug to treat the rapid-aging disease progeria
An oral treatment blocks the buildup of defective proteins in the body. The U.S. Food and Drug Administration has approved a treatment that could give children with a rare genetic illness that causes premature aging more time to live. Children with the disease, known as Hutchinson-Gilford progeria syndrome, or progeria for short, often die of heart failure, heart attack or stroke as teenagers. Most children with the disorder die before they reach age 15. The newly approved drug, called Zokinvy, is the first and only approved treatment for progeria and certain related syndromes, the FDA announced November 20. In clinical trials of 62 children receiving the drug, Zokinvy increased life span by about 3 months on average during the first three years of treatment, compared with another 81 kids who did not take the drug from a separate study that collected their health data. Following children who continued to receive Zokinvy for up to 11 years showed that, on average, kids’ life spans were lengthened by about 2.5 years. “This is not a cure,” cautions Monica Kleinman, a pediatric critical care doctor at Boston Children’s Hospital who was involved with the clinical trials. “We’ve hopefully extended the life span that [the children] have by slowing the pace of the disease,” but, she says, the drug doesn’t give kids a normal length of life. An estimated 350 to 400 kids across the world have progeria. For these children, a single mutation in their genetic code upends their health (SN: 2/7/13). That mutation interferes with the gene responsible for making the protein lamin A, which helps hold cells’ nuclei together. Children with progeria end up with higher amounts of a defective protein called progerin, which is similar to lamin A but with an extra piece attached. This protein gets stuck in cells’ membranes and can’t be recycled for fresh proteins, causing the cells to prematurely age and making blood vessels and connective tissue stiffer, Kleinman says.
11-25-20 California cave depicts hallucinogenic plant, study finds
Cave art in California created by indigenous Americans about 400 years ago depicts a hallucinogenic plant, according to new research. Pinwheel Cave in southern California gets its name from a red, wheel-shaped drawing on its ceiling. Researchers had previously discovered the chewed remains of plants, stuffed in crevices in the ceiling of the cave. Now the remains have been confirmed as Datura, a plant used historically for its psychoactive effects. While many have believed that prehistoric rock art was influenced by hallucinogens, this latest research suggests that the rock painting at Pinwheel Cave depicted the Datura plant itself, rather than any visions caused by the plant, the study said. However, the findings do present "the first clear evidence for the ingestion of hallucinogens at a rock art site", the study, which was published in the Proceedings of the National Academy of Sciences, added. "I was like: 'Wow, we found the smoking gun of hallucinogens at a rock art site,'" David Robinson, a lecturer in archaeology at the University of Central Lancashire who led the study, told ScienceMag.org. The painting showed the artist was "representing the plant that causes the hallucinogenic experience - not the vision that is caused by the plant," Dr Robinson said, adding that "they're venerating the plant, saying: 'That plant's cool.'" Sandra Hernandez, a Tejon tribal member who worked on the study, agreed that the art was depicting the flower. "I kind of marvelled at the shapes that they captured in the rock art compared to the actual flower unfurling," she said. The discovery of various different tools and food scraps suggest that the cave was likely a communal area, the researchers said, and the rock art could have been "acting as visual catalysts for communal experiences". The artwork could have helped with "setting the scene", like religious artwork in other settings, to help people who were sharing the tradition of taking the hallucinogenic plant in that cave, Dr Robinson told Live Science.
11-25-20 Climate change has revealed a huge haul of ancient arrows in Norway
An extraordinary number of arrows dating from the Stone Age to the medieval period have melted out of a single ice patch in Norway in recent years because of climate change. Researchers from the Universities of Cambridge, Oslo and Bergen gathered up a total of 68 arrow shafts, some with arrow heads still attached or nearby, and many other artefacts. Almost all of the items were found on an area of mountainside no bigger than 18 hectares in Jotunheimen, a region of southern Norway. The oldest arrows date from around 4100 BC while the youngest are from roughly AD 1300, based on radiocarbon analysis. However, the dates aren’t evenly distributed across the millennia, raising questions about whether environmental conditions during some periods were more likely to preserve fallen arrows than at other times. Peaks and troughs in reindeer hunting activity could also have played a role. In some cases, arrowheads of various materials have also survived, including bone, slate, iron, quartzite and one made of mussel shell. A few arrowheads even retain the twine and tar used to fix them to their wooden shaft. Based on the nearly 300 specimens of reindeer antler and bone also secreted by the ice, and the fact that reindeer still frequent the area, the archaeologists are confident that the area served as a key hunting ground for millennia. Other artefacts from the site include a beautifully preserved 3000-year-old shoe and textiles that the archaeologists say may have been used to package meat. The finds represent a “treasure trove”, says William Taylor at the University of Colorado Boulder, who wasn’t involved in the work. He notes that it is very unusual to recover so many artefacts from melting ice at one location. “You might expect a handful of items if you were lucky,” he says. “It’s extremely rare and extremely important.”
11-24-20 Reading Facebook comments on news articles can make you a toxic person
Engaging with the comments on Facebook posts about news articles makes you a more toxic person, an analysis of nearly 6.5 million comments suggests. Jason Reifler at the University of Exeter, UK, and his colleagues gathered the comments from 11,305 Facebook posts published by 33 news outlets during October 2018. They then asked a polling company to survey 2200 people in the US for a nationally representative sample. The research aimed to see if online comment sections played a role in increasing toxicity both online and off. “If we see bad behaviour online, we make inferences about the larger group as a whole,” says Reifler. The participants were asked to read a sample of Facebook posts and then suggest an appropriate comment. The team ranked these comments using Google’s Perspective API tool, which is commonly used to assess the toxicity of online text. Comments are rated from 0, not at all toxic, to 1, very toxic. For example, “GOOD LEAVE FOR AFRICA” was rated 0.5, while “Lol what a loser school” was rated 0.8. The pollsters also asked participants how often they comment on Facebook. The suggested comments of people who said they never comment on Facebook ranked 0.18 on average, while those who said they did so more than once a day provided comments rated 0.23 on the toxicity scale. This might be an underestimate for the toxicity of online comments, as people may be more civil when speaking to a pollster. The team found that the average toxicity of all suggested comments was 0.19, compared with 0.33 for the actual Facebook comments. The team also wanted to find out how being exposed to toxic comments on Facebook affects people. Half of the participants were shown the Facebook posts with no comments, while the other half were shown the posts along with their “featured comments”, which Facebook selects algorithmically. The researchers claim these are often the most toxic comments, rating an average 0.9. Exposure to these feature comments increased the toxicity of language people felt willing to use with pollsters by up to 0.33, says the team.
11-24-20 Lonely brains crave people like hungry brains crave food
After being alone, people’s brains showed increased responses to pictures of other humans. A hungry brain craves food. A lonely brain craves people. After spending a day completely isolated from anyone else, people’s brains perked up at the sight of social gatherings, like a hungry person’s brain seeing food, scientists report November 23 in Nature Neuroscience. Cognitive neuroscientist Livia Tomova, then at MIT, and her colleagues had 40 participants fast for 10 hours. At the end of the day, certain nerve cells in the midbrain fired up in response to pictures of pizza and chocolate cake. Those neurons — in the substantia nigra pars compacta and ventral tegmental area — produce dopamine, a chemical messenger associated with reward (SN: 8/27/15). On a different day, the same people underwent 10 hours of isolation (no friends, no Facebook and no Instagram). That evening, neurons in the same spot activated in response to pictures of people chatting or playing team sports. The more hunger or isolation the subject reported, the stronger the effect (SN: 10/4/17). In people who reported that they were generally more lonely, the social responses were blunted. “We don’t really know what causes that,” Tomova says. “Maybe being isolated doesn’t really affect them as much, because it’s something that is not that different, perhaps, from their everyday life.” The midbrain, which plays an important role in people’s motivation to seek food, friends, gambling or drugs, responds to food and social signals even when people aren’t hungry or lonely. After all, a person always could eat or hang out. But hunger and loneliness increased the reaction and made people’s responses specific to the thing they were missing. The findings “speak to our current state,” says Tomova, now at the University of Cambridge. COVID-19 has left many more socially isolated, putting mental as well as physical health at stake (SN: 3/29/20) and leaving people with cravings for more than food. “It’s important to look at the social dimension of this kind of crisis.”
11-24-20 Immunity to COVID-19 may persist six months or more
Evidence is emerging that the coronavirus sparks potentially lasting protection in some people. As coronavirus cases in the United States and around the world rise, scientists are uncovering hints that immunity for those who have had COVID-19 can last at least six months, if not longer. After people with COVID-19 have largely recovered, immune proteins called antibodies are still detectable six months later. What’s more, the proteins have sharpened their skills at fighting the coronavirus, researchers report in a preliminary study posted November 5 at bioRxiv.org. Leftover pieces of the virus remaining in the gut after symptoms have disappeared may help the immune system work to refine that response. The finding also bodes well for how long a vaccination might provide protection. Immunity from a vaccine is expected to last as long or longer than natural immunity. Antibodies, which are immune proteins that bind to microbes to fight off an infection, are part of the body’s cache of immune defenses. People typically make a wide variety of antibodies during an infection. These proteins can recognize different surfaces on viruses — like a Swiss Army knife able to work on various parts of the virus — and evolve over time to better recognize their target (SN: 4/28/20). Six months after an infection with the coronavirus that causes COVID-19, called SARS-CoV-2, people appear to have built an arsenal of antibodies that are not only more potent than the ones developed early on, similar to what has been seen in other infections. Those antibodies can also recognize mutated versions of the virus, researchers found. In addition to antibody upgrades, long-lasting immune cells that make antibodies, called memory B cells, stick around in the blood, poised to launch a rapid response should people be exposed to the virus again.
11-23-20 Meat-free diets linked with greater risk of breaking bones
People who don’t eat meat are more at risk of breaking bones, especially their hips, according to the largest study yet of this risk. The effect may stem from a lack of calcium and protein in their diet, as well as the fact that they tend to be thinner and so have less flesh to cushion a fall. Several previous studies have shown that vegetarians have weaker bones than meat eaters, but it was unclear if this had any meaningful effect on their risk of fractures. The new research took advantage of a long-running study called EPIC-Oxford, originally set up to look at whether diet influences the risk of cancer by following the health of about 65,000 people in the UK from 1993 onwards. The study recorded people’s typical diet and tracked their health through hospital records. By 2010, vegans had broken a hip at over twice the rate of meat eaters, while vegetarians and fish eaters had a smaller increase in risk, of about 25 per cent. Vegans – but not vegetarians and pescetarians – also had a higher risk of breaking other bones. The overall level of risk to vegans was relatively small, equating to about an extra 20 bones broken per 1000 people over 10 years. But the fracture rate is likely to be higher in the elderly, who break hips more often, as the average age of participants at the start was 45, says researcher Tammy Tong at the University of Oxford. When people’s diets were analysed, meat eaters consumed more calcium and protein. Calcium is an important component of bones, and protein may aid calcium absorption from food. “Unless they are actively supplementing, it’s quite unlikely that vegans will have a sufficient intake of calcium just from the diet,” says Tong. But it is possible that people eating a vegan diet today may have higher calcium levels. “In the 1990s, there was less fortification of plant milks,” she says.
11-23-20 Newton’s groundbreaking Principia may have been more popular than previously thought
Researchers found over 300 copies of the book’s first edition. Isaac Newton’s 17th century book, the Principia, gave the famed English scientist a reputation: “[T]here goes the man that writt a book that neither he nor any body else understands,” a Cambridge student is said to have remarked as Newton passed by one day. Likewise, historians have assumed that only a select few scientists and mathematicians were able to comprehend the highly technical book, which introduced game-changing physics concepts such as the universal law of gravitation. But a new census, described September 2 in Annals of Science, of the remaining copies of the book’s first edition suggests that the student’s quip was misleading. “An anecdote only tells you part of the story,” says study coauthor and historian of science Mordechai Feingold of Caltech. A 1950s search found only 189 copies of the first edition, published in 1687 under the full title Philosophiae Naturalis Principia Mathematica (SN: 7/4/87). But Feingold and his former student Andrej Svorencík, now at the University of Mannheim in Germany, unearthed 386 copies, suggesting a more substantial readership. By tracking down original owners and studying the annotations that readers made, the researchers conclude that, in addition to scientists, well-educated laypeople were reading the book too.
11-23-20 The biblical warrior Goliath may not have been so giant after all
The width of his home city’s walls were possibly used to metaphorically represent the champion’s height. Early versions of the Bible describe Goliath — an ancient Philistine warrior best known as the loser of a fight with the future King David — as a giant whose height in ancient terms reached four cubits and a span. But don’t take that measurement literally, new research suggests. Archaeological findings at biblical-era sites including Goliath’s home city, a prominent Philistine settlement called Gath, indicate that those ancient measurements work out to 2.38 meters, or 7 feet, 10 inches. That’s equal to the width of walls forming a gateway into Gath that were unearthed in 2019, according to archaeologist Jeffrey Chadwick of Brigham Young University in Provo, Utah. Rather than standing taller than any NBA player ever, Goliath was probably described metaphorically by an Old Testament writer as a warrior who matched the size and strength of Gath’s defensive barrier, Chadwick said November 19 at the virtual annual meeting of the American Schools of Oriental Research. People known as Canaanites first occupied Gath in the early Bronze Age, roughly 4,700 to 4,500 years ago. The city was rebuilt more than a millennium later by the Philistines, known from the Old Testament as enemies of the Israelites (SN: 11/22/16). Gath reached its peak during the Iron Age around 3,000 years ago, the time of biblical references to Goliath. Scholars continue to debate whether David and Goliath were real people who met in battle around that time. The remains of Gath are found at a site called Tell es-Safi in Israel. A team led by archaeologist Aren Maeir of Bar-Ilan University in Ramat-Gan, Israel — who Chadwick collaborated with to excavate the Gath gateway — has investigated Tell es-Safi since 1996. Other discoveries at Gath include a pottery fragment inscribed with two names possibly related to the name Goliath. Evidence of Gath’s destruction about 2,850 years ago by an invading army has also been recovered.
11-22-20 It's not just the germs — it's also the genes
Pathogens can make us sick. Just how sick depends on genetic variations, including ones that sabotage immune molecules called interferons. At first glance, the cause of severe infectious disease seems obvious: The culprit is a bacterium, a virus, or some other pathogen. Yet this can't be the full story. After all, there are plenty of differences in a given pathogen's effects from one person to the next, notes Jean-Laurent Casanova, a human geneticist of infectious disease at Rockefeller University. This clinical variability, he says, "is the fundamental infection enigma." Various factors contribute. Another disease or condition may have made the body more vulnerable, or the immune system may have weakened with age. And maybe one person got a larger dose of the pathogen than another did. But according to Casanova, the enigma is something beyond that. Time and again, he has seen children who are seriously ill from infections that left their relatives untouched. And over the past 25 years, he and his colleagues have shown that severe infectious disease symptoms can often be related to uncommon variations found in patients' genes. Some of these genetic variants (small differences in bits of DNA) cause "primary immunodeficiencies" that make people vulnerable to many different infections — because, for example, they don't produce white blood cells called lymphocytes that protect against a range of pathogens. In other cases, people may be more vulnerable to severe illness caused by a particular group of microorganisms, such as the mycobacteria that cause diseases like tuberculosis, or the herpes simplex virus, which causes mild symptoms in most people but deadly encephalitis in some. As the COVID-19 pandemic roils on, Casanova and others are finding genetic variants that help to explain the differing reactions to SARS-CoV-2 — from absent or mild symptoms all the way to serious sickness and death. And yet again, facets of the immune system appear to be involved — notably, a set of signaling molecules called interferons. The germ theory of disease, established in the late 1800s, revolutionized human medicine, ultimately ushering in a bevy of advances such as the development of antibiotics, antivirals, and vaccines as well as public health measures to prevent infections and their spread. But Casanova and his colleague Laurent Abel argue in the Annual Review of Pathology: Mechanisms of Disease that the success of germ theory may have eclipsed the importance of genetic variability in our species. Clearly, there can be no infectious disease without a pathogen. "You need to be exposed, of course," says Abel, a human geneticist at Inserm in Paris, "and the intensity of exposure may play a role." But even when all things seem to be equal, a great deal of variability in people's responses often remains, he says. And the reason for that, Abel and Casanova hypothesize, often lies in the genetics of our immune response, and what researchers call inborn errors of immunity. The term doesn't necessarily imply that a genetic variant causing severe disease is bad across the board. Though it might make a person vulnerable to severe disease caused by one pathogen, it might provide better protection against another, or lower the risk of inflammatory disorders caused by hyperactive immune systems. Last year, for example, Abel, Casanova, and colleagues reported that possessing two copies of a certain variant of a gene called TYK2 makes people more likely to develop tuberculosis after infection with the bacterium that causes it. That same gene variant offers protection against rheumatoid arthritis.
11-21-20 Here’s why COVID-19 vaccines like Pfizer’s need to be kept so cold
Freezing RNA-based vaccines keeps their fragile components from breaking down. Pfizer is racing to get approval for its COVID-19 vaccine, applying for emergency use authorization from the U.S. Food and Drug Administration on November 20. But the pharmaceutical giant faces a huge challenge in distributing its vaccine, which has to be kept an ultrafrosty –70° Celsius, requiring special storage freezers and shipping containers. It “has some unique storage requirements,” says Kurt Seetoo, the immunization program manager at the Maryland Department of Public Health in Baltimore. “We don’t normally store vaccines at that temperature, so that definitely is a challenge.” That means that even though the vaccine developed by Pfizer and its German partner BioNTech is likely to be the first vaccine to reach the finish line in the United States, its adoption may ultimately be limited. The FDA’s committee overseeing vaccines will meet on December 10 to discuss the emergency use request. That meeting will be streamed live on the agency’s web site and YouTube, Facebook and Twitter channels. The companies are also seeking authorization to distribute the vaccine in Australia, Canada, Europe, Japan, the United Kingdom and other parts of the world, making its deep-freeze problem a global challenge. A similar vaccine developed by Moderna and the U.S. National Institute of Allergy and Infectious Diseases also requires freezing. But it survives at a balmier –20° C, so can be kept in a standard freezer, and can even be stored at refrigerator temperatures for up to a month.. Most vaccines don’t require freezing at all, but both Pfizer and Moderna’s vaccines are a new type of vaccine for which the low temperatures are necessary to keep the vaccines from breaking down and becoming useless.
11-21-20 These plants seem like they’re trying to hide from people
A plant used in Chinese traditional medicine has evolved camouflage in heavily harvested areas. Fritillaria plants should be simple to spot. The usually bright green plants often stand alone amid the jumbled scree that tops the Himalayan and Hengduan mountains in southwestern China — easy pickings for traditional Chinese medicine herbalists, who’ve ground the bulbs of wild Fritillaria into a popular cough-treating powder for more than 2,000 years. The demand for bulbs is intense, since about 3,500 of them are needed to produce just one kilogram of the powder, worth about $480. But some Fritillaria are remarkably difficult to find, with living leaves and stems that are barely distinguishable from the gray or brown rocky background. Surprisingly, this plant camouflage seems to have evolved in response to people. Fritillaria delavayi from regions that experience greater harvesting pressure are more camouflaged than those from less harvested areas, researchers report November 20 in Current Biology. The new study “is quite convincing,” says Julien Renoult, an evolutionary biologist at the French National Centre for Scientific Research in Montpellier who wasn’t involved in the study. “It’s a nice first step toward demonstrating that humans seem to be driving the very rapid evolution of camouflage in this species.” Camouflaged plants are rare, but not unheard of, says Yang Niu, a botanist at the Kunming Institute of Botany in China, who studies cryptic coloration in plants. In wide open areas with little cover, like mountaintops, blending in can help plants avoid hungry herbivores (SN: 4/29/14). But after five years of studying camouflage in Fritillaria, Niu found few bite marks on leaves, and he did not spot any animals munching on the plants. “They don’t seem to have natural enemies,” he says.
11-20-20 What are the odds of dying if you're infected by the coronavirus?
The proportion of people who die after being infected by the coronavirus has become highly controversial. Some have claimed that death rates aren’t as high as thought and that governments are overreacting by imposing measures such as lockdowns. But a recent meta-analysis confirms earlier estimates, finding that the death rate can be as high as 16 per cent for people over 90 but 0 per cent for children under 4. This study concludes that in high-income countries, more than 1 in 100 people infected by the coronavirus died in the first wave. “The death rate is at least 10 or 20 times higher than flu,” says Nicholas Brazeau at Imperial College London. More of the people admitted to hospital with covid-19 are surviving now, suggesting that the death rate has fallen slightly. However, if hospitals in some countries are overwhelmed during the surge of infections now hitting Europe and the US, that might not continue to be the case. Estimating the real death rate is hard for two reasons. First, the odds of dying from covid-19 vary greatly depending on a person’s age, sex, health and the standard of care received. This means death rates will vary from place to place and at different times. For instance, the death rate is highest in care homes: as high as 73 per cent in nursing homes in Belgium, one study estimated. In countries such as South Korea that have managed to largely prevent outbreaks in care homes, the overall death rate is lower. Similarly, vaccines that prevent severe disease in older people should reduce death rates. The second reason it is hard to estimate the real death rate is that there is great uncertainty about the numbers used to calculate it. What we want to know is how many people who get infected with the virus actually die: the infection fatality rate. The best way we have of working out how many people have been infected is to test the blood of thousands of people to see how many have antibodies to the coronavirus, and then extrapolate those results to entire countries. But antibody surveys can produce misleading results.
11-20-20 Ancient parasites in a titanosaur’s bones made it look like a zombie
Some of the oldest evidence of bone disease may have been caused by tiny 83-million-year-old parasites infecting a titanosaur, which are among the largest land animals that ever lived. This is the first discovery of parasites in a dinosaur bone. “It’s a new kind of parasite,” says Aline Ghilardi at the Federal University of Rio Grande do Norte in Brazil. “We don’t have anything similar to it.” This fossilised parasite was seen in a sample from a dwarf titanosaur, a species first identified from a leg bone found in a deposit near São Paulo, Brazil, in 2009 that dated to the late Cretaceous period. The dwarf titanosaur species, dubbed “Bilbo”, would have been 5 or 6 metres long, a little smaller than most titanosaurs. “It’s our hobbit titanosaur,” says Ghilardi. She and her team analysed a sample of the leg bone, cutting thin sections of the fossil and analysing them using a medical CT scanner. The researchers found that the dinosaur was old and infirm. They analysed strange, spongy bumps on its bones, and found that they were probably due to an aggressive form of osteomyelitis, a type of bone infection often spread by fungi, bacteria or protozoa. Based on the way the infection typically works in animals or humans today, they deduced that the state of the disease was so advanced that this dwarf titanosaur would have been covered in open wounds. The team gave it another nickname: Dino Zombie. Further analysis also revealed microorganisms that were present in the dwarf titanosaur’s blood when it died. Ghilardi says these might be large protozoans or nematode worms, and could have even been the cause of the bone infection, although it is difficult to say for sure. The parasite seems to be something we have never seen before, she says, and learning more about it could teach us about how modern related diseases evolved.
11-20-20 50 years ago, scientists named Earth’s magnetic field as a suspect in extinctions
Excerpt from the November 21, 1970 issue of Science News. Earth’s magnetic field has frequently reversed at intervals of 1 million to 100 million years. A few scientists now suspect that these reversals may have had drastic effects on terrestrial life.… During the past 2.5 million years, eight species of one-cell marine animals called Radiolaria became extinct. Six of these extinctions occurred simultaneously throughout their geographic range immediately following magnetic reversals. Earth’s magnetic field protects the planet from cosmic and solar radiation, but that field can weaken during pole reversals. Such reversals might harm more than select species, perhaps playing a role in some mass extinctions. Direct evidence has eluded researchers, but there are suggestive examples. In 2016, scientists linked a mass extinction of marine life 550 million years ago with reversals that weakened the magnetic field. The resulting increased radiation could have led to the demise of many shallow-water organisms, the team speculated.
11-20-20 Plate tectonics may have begun a billion years earlier than thought
Plate tectonics may have begun 4 billion years ago, almost a billion years earlier than we thought, according to a new analysis of ancient rocks. The claim has earned a mixed response from geologists. Many argue that Earth was too hot at the time for plate tectonics in its modern form. Today, Earth’s crust is divided into several dozen rigid plates, which move around over millions of years. Where two plates meet, one can be forced under the other and destroyed inside the planet, a process called subduction. Plate boundaries are prone to earthquakes and are dotted with active volcanoes. It is clear that plate tectonics has operated for hundreds of millions of years. But Earth is 4.5 billion years old, and for many years geologists have disagreed over when plate tectonics started, and what the planet was like beforehand. There has been a growing consensus that plate tectonics started about 3.2 billion years ago. But according to Brian Windley at the University of Leicester in the UK, that is wrong. “It really is a great misunderstanding of so many things,” he says. Instead, Windley and his colleagues argue that tectonics began much earlier, at least 4 billion years ago. The evidence of a shift 3.2 billion years ago, they say, merely reflects a change in the way the plates were behaving. The team re-examined data from rocks laid down between 4 and 3.2 billion years ago. They argue that many of them contain evidence of mountain-building, but of a particular kind seen today in a few places, including Japan and the Caribbean. When two oceanic plates meet, one gets subducted, and the volcanic activity this generates can lead to the formation of a chain of volcanically active islands. “You get island arcs, like those in the western Caribbean today,” says Windley.
11-19-20 Potent new antifungal discovered in the microbiome of marine animals
A new antifungal compound that is effective against even multidrug-resistant fungi has been found in the microbiome of a marine animal. Fungal infections affect hundreds of millions of people globally each year. “They’re particularly a problem for people whose immune system is suppressed,” says David Andes at the University of Wisconsin–Madison. This includes people being treated for cancer, organ transplant recipients and premature babies. The new compound may help because it is effective against many fungal pathogens that infect humans, including Aspergillus fumigatus and Candida auris. Andes and his colleagues found the compound – a molecule that they named turbinmicin – inside Micromonospora bacteria that live within sea squirts, which are filter feeders. They made the discovery by screening bacteria that they had isolated from a variety of marine animals. The team searched for bacteria with promising chemical fingerprints and found that turbinmicin targeted a fungal protein called Sec14p, which no other antifungal drugs target. Turbinmicin’s efficacy against C. auris is promising given that the fungus, which is contagious, appears to have developed resistance to almost all other currently available antifungal drugs. “It spreads from patient to patient and spreads from the healthcare setting to patients, so we get outbreaks,” says Andes. Many antimicrobial drugs have originated from discoveries made by studying bacteria that live on land, but less research has been done on ocean-dwelling bacteria, says Tim Bugni, also at the University of Wisconsin–Madison. “There’s an immense amount of bacterial diversity there that had never been looked at for drug discovery.” One of the challenges of developing antifungal drugs is potential toxicity, because of similarities between fungi and human cells. Both fungi and humans are eukaryotes – organisms with complex cells containing a nucleus and organelles that are bound by membranes.
11-19-20 Ebola outbreak in the DRC ended thanks to vaccine distribution efforts
The Democratic Republic of the Congo (DRC) has declared an official end to its 11th Ebola outbreak nearly six months after it began, marking the first time in years the vast central African country has been free of the deadly haemorrhagic fever. Eteni Longondo, the DRC’s minister of health, and the World Health Organization (WHO) made the announcement on 18 November after no new cases of the viral disease had been recorded in the country’s western Équateur province for more than 48 days. In this outbreak, there were 55 deaths and 75 people who had recovered out of 119 confirmed and 11 probable cases. The outbreak, which was announced on 1 June, surfaced shortly before the DRC called an end to a separate Ebola epidemic – hundreds of miles away in the east of the country – that killed 2280 people over nearly two years. Genetic sequencing showed that the two virus strains were unrelated. The latest outbreak stretched vast distances across dense rainforests and remote waterways as well as busy urban areas. It was halted thanks to “cold chain” vaccine storage technology and community-based health workers who vaccinated 40,000 people deemed at high risk of contracting the disease, according to experts. “The geography was very difficult in terms of accessibility,” says Ngoy Nsenga at the WHO. “It required serious logistics, and so this ultracold-chain technology was very important.” Known as the Arktek and originally developed by Global Good, a US-based technology company, the cylinder-shaped “super thermos” devices can store 500 vaccine doses at -80°C for up to a week with no external power source. This meets the cold temperature requirements of the Merck Ebola vaccine, as well as those of Pfizer’s new covid-19 vaccine, which bodes well for vaccination in lower-income countries with less-developed infrastructure.
11-19-20 Your eyes can reveal your decisions before you've even made them
Choosing between going out for a run or staying slumped on your sofa can be a tricky call, but it turns out your eyes can reveal your decision before you have even made it. When we do something that requires physical effort, our pupils can dilate and activity heightens in the prefrontal cortex, the part of the brain involved in cognition. Now, it seems that these two reactions may also guide our decisions about activities that we have yet to carry out. To investigate this idea, Irma Kurniawan and her colleagues at the University of Zurich in Switzerland asked 49 people to choose between different tasks that varied by their level of effort. The researchers first trained the participants to do sets of hand squeezes using a handheld device at varying levels of physical difficulty. Each person was then placed inside a functional MRI scanner to record their brain activity while an eye tracker also monitored their pupil size. Participants were asked to choose between more strenuous or effortless hand contractions, with a greater cash reward for choosing the more difficult exercises. Once outside of the scanner, 30 minutes to an hour later, the participants completed a random selection of hand squeezes at their chosen levels of effort. The team saw changes in pupil size and prefrontal cortex activity as people made their decision. Because these changes occurred before the participants had actually carried out the exercises, it suggests that people were anticipating the amount of effort they would require. What’s more, if someone chose the most difficult activity, this was revealed by specific pupil dilation and brain activity patterns. The team suggest these signals influence the outcome of people’s decisions, by helping to predict the amount of energy they will require, and this reveals whether people will end up doing a higher effort task.
11-19-20 Very hangry caterpillars could help reveal genetic basis of aggression
Very hungry monarch caterpillars get hangry, resulting in them headbutting and lunging at other caterpillars in an attempt to secure food. “The less food that is present, the higher their level of aggression,” says Elizabeth Brown at Florida Atlantic University. Monarch caterpillars, found across North and Central America, only eat milkweed leaves. Brown and her team gave the caterpillars three different amounts of food and found that they attacked each other significantly more when the leaves were scarce. Larger monarch caterpillars – those in the final stages before starting to transform into butterflies – often showed the highest levels of aggression, probably because they need more food, says Brown. “There’s a clear winning caterpillar and losing caterpillar,” she says. “This often scales with their size.” The hungry caterpillars only attack when their target is actively feeding, and this never occurred while a caterpillar was resting. The attacking caterpillar seeks to disrupt feeding and claim a food source for itself. “You can often see a single caterpillar strip down an entire plant of its leaves,” says team member Alex Keene, also at Florida Atlantic University. “So, there is a big cost to these caterpillars if there are three of them on a plant with you.” Many animals become aggressive when competing for food. The researchers hope to learn more about the genetic basis for aggression by studying the caterpillars. “There’s a lot we could learn about more complex animals from this ecologically relevant insect model,” says Keene.
11-19-20 Monarch caterpillars head-butt each other to fight for scarce food
As milkweed supplies dwindle, the insects turn up the aggression, lab experiments show. When food and space get scarce, competition can bring out the worst in monarch caterpillars. In the laboratory, researchers watched as roaming caterpillars looking for a hard-to-find meal started head-butting and lunging at fellow caterpillars munching on a milkweed leaf. That aggressive behavior is apparently meant to disrupt the feeding insects and help the instigators score dinner, biologist and neuroscientist Alex Keene and colleagues report online November 19 in iScience. Keene usually studies fruit flies and cavefish, but he decided to adapt his laboratory to study monarchs after a chance observation. “My wife pointed out in the backyard that these two monarch caterpillars were fighting with each other,” says Keene, of Florida Atlantic University in Jupiter. “I went on YouTube, and there were videos of this behavior,” he says, but for monarchs, “it wasn’t documented anywhere in the scientific literature.” Other types of caterpillars have shown similar aggressive behavior in other settings. Going from a self-proclaimed “simple fly biologist” to monarch researcher, however, was a challenge. Not only did Hurricane Dorian in 2019 blow over the plants in the lab’s monarch garden, but also finding pesticide-free milkweed plants that the caterpillars would eat was harder than expected. Once the researchers overcame these challenges, though, they were able to film caterpillars competing with one another when the researchers limited the amount of available food.
11-18-20 What are mRNA vaccines and how useful will they be?
A collective wave of excitement swept around the world when Pfizer and BioNTech announced positive early results from their coronavirus vaccine trial last week. Now, biotechnology firm Moderna has announced even better findings. These are no ordinary vaccines: they could be the first messenger RNA (mRNA) vaccines to be approved. If this technology lives up to its promise, it could bring huge benefits for healthcare, not just for tackling the coronavirus. “Part of the reason why the results from Pfizer are so exciting is that nobody has ever shown in humans that an mRNA vaccine can be effective,” says Anna Blakney at Imperial College London, who is working on a different vaccine. “I think it will change the way we make a lot of vaccines.” Viruses consist of the recipe for making more viruses wrapped in a protein coat. Our immune system fights them by learning to recognise that outer protein. Almost all vaccines physically contain such a viral protein in some form. Many vaccines contain entire viruses, coat proteins and all, using either harmless strains of dangerous viruses or inactivated viruses. Some more modern ones, called subunit vaccines, just contain the outer protein. All of these vaccines are tricky to develop and manufacture, not least because viruses and proteins can only be made in living cells. Flu vaccines are typically grown in chicken eggs, for instance. By contrast, mRNA vaccines contain the instructions for making the viral protein instead of the protein itself. mRNAs are an essential part of cellular biology – they are copies of the genes in our genome and act as a template for making proteins. If mRNAs that code for a viral gene are added to a human cell, the cell will start making that viral protein and continue to make it for several weeks until the mRNAs break down. Because only the outer protein is made, not the whole virus, there is no chance of an actual infection.
11-18-20 Ardi and her discoverers shake up hominid evolution in ‘Fossil Men’
A new book blends science and drama to tell the story of a major paleoanthropology find. She is the most controversial, convention-defying, weirdest-looking fossil hominid ever found. Fittingly, the group that discovered this 4.4-million-year-old adult female, nicknamed Ardi, includes the most controversial, convention-defying (and some would say weirdest-acting) fossil hunters and bone analysts to have ever wrestled with the puzzle of how humans and our ancestors evolved. In Fossil Men, journalist Kermit Pattison recounts intriguing backstories of the Ardi scientists and how they came to challenge popular views of hominid evolution. Many incidents in the book show the courage and grit it took to find and excavate Ardi in Ethiopia’s remote Middle Awash area, where local nomadic groups are prone to shoot at outsiders. Pattison also examines how Ardi’s skeleton makes her a one-of-a-kind find. Standing at the center of this ancestral spectacle is team leader Tim White, a paleoanthropologist at the University of California, Berkeley. A demanding and intense taskmaster in the field, White has a hard-earned reputation as one of the all-time great fossil hunters. Pattison describes White as having remarkably keen eyes for assessing fossil bones and a knack for brutal, sarcastic takedowns of evolutionary arguments (and scientists) he finds deficient. In a published review of an eminent anthropologist’s book claiming that hominid evolution included many species, White called him a purveyor of “politically correct paleoanthropological pontification” that didn’t rise to the level of fiction such as The Clan of the Cave Bear. Not surprisingly, White has amassed scientific enemies since the early 1970s, when he worked with members of the fossil-hunting Leakey family in Africa. He takes his professional infamy in stride. “With decreasing food availability, we find increased levels of aggression,” as well as a “loser response,” with the caterpillar that gets attacked often leaving the area, says Elizabeth Brown, a biologist who works in Keene’s lab. This kind of behavior does occur outside the lab, says Jaap de Roode, a biologist at Emory University in Atlanta who wasn’t involved in the research. Competition can be tough, he adds, because monarch caterpillars are limited in their food options. The insects eat only milkweed, and are more or less stuck on the plant that they’re born on until they bulk up, because crawling from plant to plant takes energy (SN: 7/10/18). If there isn’t enough food from the one plant to feed several caterpillars, “they won’t make it,” he says.
11-18-20 Our supposed earliest human relative may have walked on four legs
AFTER more than a decade in limbo, a crucial fossil of an early human relative has finally been scientifically described. The leg bone suggests that Sahelanthropus tchadensis, the earliest species generally regarded as an early human, or hominin, didn’t walk on two legs, and therefore may not have been a hominin at all, but rather was more closely related to other apes like chimps. A paper from a rival group, not yet peer-reviewed, disputes this. The studies are the latest twist in a bitter saga that has seen the fossil held back from publication and its existence ignored. “We have been anxiously awaiting the publication of this femur for many years,” says Kelsey Pugh at the American Museum of Natural History in New York. Michel Brunet from the University of Poitiers in France and his colleagues discovered the remains of Sahelanthropus tchadensis in Chad in 2001. The team described a skull, dubbed Toumaï, plus fragments of lower jaw and some teeth (Nature, doi.org/c66kw6). Brunet and his colleagues have always maintained that Sahelanthropus habitually walked on two legs – like modern humans but unlike chimpanzees and other apes. This was based on an analysis of the base of the skull, suggesting that the spine was held upright. Many other researchers have argued that this isn’t sufficient evidence for bipedality. Resolving this is key, because the Sahelanthropus bones are believed to be 7 million years old, far older than other human relatives like Australopithecus. If it was a biped, that would make it the oldest known hominin. If not, it may not be that closely related to us. The researchers found a femur, or thigh bone, along with two ulnas, or forearm bones, that would help clarify the matter, but they published nothing about them for almost two decades, prompting criticism from colleagues. Brunet didn’t respond to a request for comment from New Scientist.
11-18-20 Let's appreciate how extraordinary the vaccines are
Science to the rescue. It's not hard to paint a bleak picture of America's battle with COVID-19. Cases are surging around the country, including in areas that suffered badly during the first wave. Nor is it a mere artifact of better testing; sewage data from Massachusetts, for example, indicates that the actual prevalence of the virus is comparable to where it was in the worst days of April, and still rising. Nationally, deaths have surpassed a quarter of a million, which is likely a significant underestimate. Hospitals are being stressed to the breaking point, and since the current wave is truly national in scope, there's no way for volunteers to bolster hard-hit areas as so many health care workers from across America did for New York back in the spring. But since the beginning of the pandemic, I've never been more optimistic. The reason is the steady tide of substantial good news on the vaccine front. First Pfizer's vaccine proved 90 percent effective — vastly exceeding the minimum level of 50 percent to be worth deploying. Then Moderna announced a vaccine of their own that was even more effective and that didn't require ultra-refrigeration to store. Moreover, these are not the only vaccines in the pipeline; though many won't pan out, the odds are extremely good that we will have at least a few workable options in early 2021. And the latest evidence suggests that immunity will generally be lasting. That's the first true sign of a light at the end since we entered this viral tunnel, and it is far brighter and closer than we had any reason to expect. We should stop for a moment to recognize how extraordinary an achievement this truly is. The normal timeline for vaccine development, after all, is measured in years, not months. Nor is this just a consequence of bureaucratic red tape or an abundance of caution about safety; the initial research phase for vaccines often leads down blind alleys. There were numerous reasons to worry that we might never get a vaccine for COVID-19: it was novel virus, in a class known for rapid mutation and rapidly-declining immunity in the infected, and for which vaccines had never been developed before. So we should be ecstatic that we've beaten the odds. Through a combination of hard work, brilliant science, sensible policymaking, and plain old good luck, we're in a position to be debating when, not whether, the pandemic is going to end. We should be re-evaluating sharply upward our overall sense of the capabilities and potential of our pharmaceutical and biotechnology industries. Frankly, if people want to make comparisons to the Manhattan Project and the Moon Landing, they shouldn't be deterred. But they might be. Indeed, there's been a distinct tone of pushback from some quarters — an almost peevish unwillingness to celebrate the good news. Part of that pushback involves legitimate warnings that we mustn't let down our guard. A vaccine isn't a cure, and plenty of people could die or suffer long-term harm from the virus before a vaccine is ever distributed. Moreover, the better we have the pandemic under control when the vaccine becomes widely available, the more effective it will be at obliterating the virus as the few infected people fall to find new hosts.
11-18-20 Toads on tropical islands are rapidly shrinking as they evolve
Toads that invaded two tropical islands have shrunk in size by a third in less than a century, a remarkably short time on evolutionary timescales. The guttural toad (Sclerophrys gutturalis) is native to large parts of Africa. A population from Durban in South Africa was introduced to the Indian Ocean islands of Mauritius and Réunion, in 1922 and 1927 respectively. Now, researchers have found the female toads on Mauritius are up to 33.9 per cent smaller than the original Durban population, and the females on Réunion up to 25.9 per cent smaller. The males shrank on Mauritius, but not on Réunion. Such shrinking in amphibians on islands normally takes thousands or millions of years. Islands have long been known as unique test beds to see how animals adapt and evolve – from dwarfism to the gigantism famously demonstrated by giant tortoises of the Galapagos islands – though it can be hard to tell how long the changes take. Recent introductions of species by humans, deliberate or not, make those shifts easier to track. It isn’t yet clear how and why the island guttural toads have shrunk, says James Baxter-Gilbert at Stellenbosch University, South Africa. His team caught and measured 158 toads on Mauritius, 186 on Réunion and 151 in Durban, between June 2019 and March 2020. The mechanism could be natural selection. Alternatively, the species may already have possessed the ability to shrink – phenotypic plasticity – given the right changes in its environment. “However, if this is a product of natural selection and functional adaptation, then this is quite a bit more surprising,” says Baxter-Gilbert, because of the speed at which the change occurred. One possible driving force is that the frogs appear to be breeding year-round on the islands, whereas they breed seasonally elsewhere. If females don’t need to bulk up and store more energy for producing a lot of eggs in a short period, they may not need to grow so large.
11-18-20 How massive long-necked dinosaurs rose to rule the Jurassic herbivores
Volcanic activity may have altered plant life and ushered in rise of dinosaur giants. Long-necked sauropods, the largest animals ever to walk on Earth, may have thundered into dominance during the Jurassic Period thanks to a large burst of volcanic activity that began around 184 million years ago, a new study suggests. The resulting environmental crisis may have caused a shift in plant life that gave the tough-toothed, big-gutted herbivores a powerful advantage over other herbivores. The find comes from the discovery of a new fossil of one of the earliest “true” sauropods in Argentinian Patagonia. Sediments bearing the newly described dinosaur, dubbed Bagualia alba, are precisely dated to 179 million years ago, paleontologist Diego Pol of the Paleontological Museum Egidio Feruglio in Trelew, Argentina, and colleagues report November 18 in Proceedings of the Royal Society B. B. alba, the researchers found, had the telltale characteristics of true sauropods: large, column-like legs; massive size; long necks relative to the body; broad and strong jaws; and large, spoon-shaped teeth with thick enamel. Also known as eusauropods, this lineage came to dominate the Middle and Late Jurassic roughly 174 million to 145 million years ago (SN: 7/10/18), giving rise to awe-inspiring giants such as Argentinosaurus and Dreadnoughtus schrani (SN: 6/9/15). During the Early Jurassic, between about 201 million and 174 million years ago, Pol says, plant-eating sauropods competed with many other herbivores, including sauropodomorphs — distant relatives such as Mussaurus patagonicus with less powerful jaws and shorter necks (SN: 5/20/19). What gave the eusauropod giants a leg up on their herbivorous competition has been unclear, in part because there are relatively few fossils dating to the transition between Early and Middle Jurassic.
11-17-20 Psilocybin may help treat depression, a small study finds
Benefits of the compound, found in psychedelic mushrooms, lasted a month. Hallucinogenic mushrooms’ key ingredient, psilocybin, can swiftly and dramatically ease depression in the right therapeutic setting, a small study suggests. A month after receiving two doses of the psychedelic drug, 13 people had big drops in depressive symptoms, researchers report November 4 in JAMA Psychiatry. Because the study was small and lacked participant diversity, it’s unclear whether the positive results would extend to wider populations. Still, “the current results are clear,” says Jay Olson, a psychology researcher at Harvard University who wasn’t involved in the study. “At least for some people, psilocybin can reduce depression better than several common treatment options.” Existing antidepressant drugs don’t work well for an estimated 30 to 50 percent of the people who try them; when they do work, the effects can take weeks to kick in. Psilocybin, a compound that can profoundly alter consciousness and perceptions of reality, might be a powerful alternative, says coauthor Roland Griffiths, a neuropsychopharmacologist at Johns Hopkins School of Medicine. In the new study, patients with moderate or severe depression received two doses of psilocybin pills spaced about a week and a half apart. Participants also received therapy and support from researchers, before, during and after taking psilocybin. A comparison group of 11 people waited eight weeks, then also received the two doses of psilocybin and supportive therapy. This delay allowed the researchers to look for improvements in symptoms that were not related to the drug. Clinicians used a common depression rating scale consisting of 17 items to measure participants’ symptoms. Scores can range from 0 to 52, with higher numbers indicating more severe depression. Before receiving psilocybin, participants who got the drug without delay scored an average of 22.9 points, signaling the high end of moderate depression. Four weeks after the second dose, average scores dropped to 8.5. A score of 7 or below indicates no depression. Scores among the comparison group hovered around 23 while those people waited their turn to get the drug.
11-17-20 Hundreds of new genomes help fill the bird ‘tree of life’
Avian genetic toolkits could let scientists unravel 150 million years of evolutionary history. From gulls to grouse to grackles, more than 10,000 bird species live on this planet. Now, scientists are one step closer to understanding the evolution of all of this feathered diversity. An international team of researchers has released the genetic instruction books of 363 species of birds, including 267 genomes assembled for the first time. Comparing all of that genetic data can help scientists figure out how the varied traits of birds — from their diverse, spellbinding songs and courtship displays to their adaptations for flight — have evolved, the team says in the Nov. 12 Nature. Birds have long received scientific attention, says ornithologist Michael Braun of the Smithsonian National Museum of Natural History in Washington, D.C., one of the researchers involved in the project. “That’s partly because birds are relatively easy to see out in nature,” he says. To compile some of the newly assembled genomes, the team took DNA from bird tissue samples in 17 scientific collections from around the world. Overall, the data cover roughly 92 percent of all modern bird families. Some species, such as chickens, are familiar; others are rare, such as the Henderson crake (Zapornia atra), found only on remote Henderson Island in the South Pacific. Scientists are just starting to uncover the secrets of avian evolution hidden in the genomes. Braun says that the data can be used better understand everything from the parallel evolution of flightlessness in ratites like emus and kiwis (SN: 4/4/19) to the evolution of vision and song learning in birds overall. Already, the researchers have found peculiarities in the genomes of passerines — the order of songbirds that includes over half of all modern bird species, though the origin of this diversity is poorly understood. These alterations include the loss of a gene involved in the development of the vocal tract, possibly influencing passerines’ songs.
11-17-20 The sale of an amazing dinosaur fossil could be bad news for science
The Duelling Dinosaurs are just the sort of remains that fossil fans dream about. Encased in huge lumps of tan sandstone are the dark bones of two dinosaurs that were buried together more than 66 million years ago. One of the fossils is a familiar three-horned Triceratops. The other is a young Tyrannosaurus, a probable cousin of T. rex, a rare representative of what the “tyrant king” was like during its gangly, awkward years. There’s no evidence that these two dinosaurs died in combat but they have still been the subject of palaeontological gossip for a decade. Enough cash has now finally been stumped up to give the bones a home. Rather than a private bidder, a museum has paid – probably millions – for the fossilised duo. Although palaeontologists should be able to examine the fossils, bone buying is a dangerous game and it isn’t clear that museums should ever shell out for specimens like this. Commercial fossil hunter Clayton Phipps and his colleagues found the skeletons in 2006 on a private ranch in Montana and undertook the excavations themselves with an eye towards a future sale. Years before, a near-complete Tyrannosaurus rex nicknamed “Sue” had been purchased for more than $8 million at auction, starting off a commercial fossil boom that started ratcheting up the market value for dinosaurs. Buzz around the Duelling Dinosaurs started to kick off in 2011. Word among experts was that the owners of the fossils were looking to sell to a national museum for a price exceeding $9 million. Yet no one bit. So the Duelling Dinosaurs went to auction at Bonhams auction house in 2013 but failed to meet the reserve price. It seemed as if the bones were in limbo – invisible to science for not being in a museum, but far too pricey for any institution to afford.
11-16-20 Your own sweat could be used to produce a natural antiperspirant
Your sweat could help stop you sweating, thanks to naturally occurring minerals such as salt and calcium that could block sweat ducts to act as an antiperspirant. Jonathan Boreyko at Virginia Tech was inspired to investigate the potential antiperspirant properties of sweat after an intense game of squash, when he noticed that salt crystals had formed on his skin. “If you could evaporate the sweat when it’s still inside the sweat duct, then maybe that sticky white salt deposit might clog the duct,” he says. Commercial antiperspirants use metal salts that block sweat ducts. Some studies have suggested that these salts have potential health risks, though overall the evidence suggests they are safe. To test whether alternatives to metal salts could make the human body produce its own antiperspirant, Boreyko and his colleagues created artificial sweat ducts out of glass tubes and filled them with a manufactured sweat solution that has the same minerals and acids as human sweat. They placed a polymer cube infused with propylene glycol – a water-absorbing substance that is often used in cosmetics and isn’t a metal salt – 100 micrometres away from the ducts. This increased the rate at which the sweat evaporated and caused the minerals within the sweat to form a plug that stopped it flowing. “I had no idea if it would work,” says Boreyko. “It’s really exciting to see it play out exactly as you imagined it in your dreams.” “The idea was to form a model and determine what are the conditions for which the duct is getting clogged,” says team member Yashasvi Lolla. The researchers plan to use this data to refine the concept and test it on real human sweat ducts.
11-16-20 A key to the mystery of fast-evolving genes was found in ‘junk DNA’
New study turns evolutionary dogma on its head by finding that essential genes can evolve fast. A long-standing puzzle in evolution is why new genes — ones that seem to arise out of nowhere — can quickly take over functions essential for an organism’s survival. A new study in fruit flies may help solve that puzzle. It shows that some new genes quickly become crucial because they regulate a type of DNA called heterochromatin. Once considered “junk DNA,” heterochromatin actually performs many important jobs, including acting like a tightly guarded prison: It locks up “bad actor” genes, preventing them from turning on and doing damage. Heterochromatin is also one of the fastest-changing bits of DNA in the body, so the genes that regulate it have to adapt quickly just to keep up, evolutionary biologist Harmit Malik at the Fred Hutchinson Cancer Research Center in Seattle and his colleagues report online November 10 in eLife. “The work is a milestone,” said Manyuan Long, an evolutionary biologist at the University of Chicago who was not involved in the research. “It is really amazing seeing such an important role the heterochromatin plays in gene evolution.” Scientists have documented many cases of genes that seem to arise from scratch and give an organism a new ability. For instance, one such gene in fish makes a novel antifreeze protein; another in flies is essential for flight. About a decade ago, researchers discovered that new genes don’t just confer new functions; some may actually be necessary for survival. In the fruit fly Drosophila melanogaster, as many as 30 percent of essential genes are “new,” with some arising as recently as 3 million years ago — a flash in evolutionary timescales. The discovery overturned a long-held belief that important genes don’t really change much over the course of evolution.
11-16-20 Three-metre-long dinosaur may have swum across a wide ocean
For the first time, the fossil remains of a duck-billed dinosaur have been found in Africa. The discovery suggests that dinosaurs sometimes swam across wide oceans, and were more capable in water than we thought. “As best we can tell, dinosaurs swam across ocean barriers,” says Nicholas Longrich at the University of Bath in the UK. Duck-billed dinosaurs, or hadrosaurs, were common towards the end of the dinosaur era. They were large animals that mostly ate plants. The bones in their snouts were flattened, giving them a duck-like appearance. Hadrosaur fossils are common in North America and Eurasia, but hadn’t previously been found in Africa. This is explained by the positions of the continents at the time at which they lived. Europe and North America were part of one large continent called Laurasia, while a second large continent called Gondwana held what are now Africa and South America. Hadrosaurs were thought to live only on Laurasia. Longrich and his colleagues obtained parts of the upper jaw of a 67-million-year-old hadrosaur from Morocco. It had been found in a phosphate mine. They have since donated the fossil to the Marrakech Museum of Natural History. There is no evidence of a land bridge linking Laurasia and Gondwana, says Longrich. The most likely explanation is that hadrosaurs crossed open water, demonstrating a swimming ability also seen in some of today’s large mammals. “Elephants swim well and they get out to islands,” says Longrich. Elephants lived on Mediterranean islands like Sicily until about 20,000 years ago. Nowadays, dinosaurs are typically thought to have been strictly terrestrial. The only large dinosaur acknowledged to have spent a lot of time in water is the predator Spinosaurus. Longrich says this might be because, decades ago, many palaeontologists thought dinosaurs would “hang out in swamps”, assuming they were too bulky to move on land. Later studies disproved this. “People realised that this hardcore aquatic dinosaur was a bunch of nonsense, and kind of overcorrected for that by saying all dinosaurs are terrestrial,” he says.
11-14-20 Measles has come back with a vengeance in the last several years
The nearly 870,000 reported cases in 2019 were largely due to outbreaks in nine countries. Measles has come back with a vengeance around the world in recent years, wiping out steep declines in cases seen since the start of the new century. From 2000 to 2016, reported measles cases worldwide plunged from 853,479 to 132,490. Cases began to rise again after that (SN: 11/30/18). In 2019, a reported 869,770 people had measles, the most since 1996, according to a study by the World Health Organization and the U.S. Centers for Disease Control and Prevention published online November 12 in Morbidity and Mortality Weekly Report. Worldwide, the estimated number of deaths from measles in 2019 was 207,500, up close to 50 percent since 2016. “This is a really important setback and a tragic setback, because we’ve had a safe and effective measles vaccine since the early 1960s,” says William Moss, an infectious disease epidemiologist at the Johns Hopkins Bloomberg School of Public Health who was not involved in the report. “We had made enormous progress.” The measles vaccine is a public health superstar, with the recommended two doses about 97 percent effective at preventing the disease and one dose about 93 percent effective. To stop outbreaks, around 95 percent of a community must be vaccinated (SN: 4/15/19). Overall, measles is infecting more people because of stalled progress in increasing immunization coverage, says coauthor Natasha Crowcroft, a senior advisor for WHO’s Measles and Rubella Control in Geneva. Globally, estimated coverage with the first dose of a measles vaccine rose from 72 to 84 percent from 2000 to 2010, but has since leveled off to around 84 to 85 percent. This “is high enough to slow measles or interrupt it for periods of time, but it inevitably leads to the accumulation of susceptible children, and eventually this flares up into outbreaks,” says Crowcroft. In 2019, 19.8 million infants did not receive the first dose of a measles vaccine. The reasons for low coverage vary by region, but weak primary health care systems and access are major factors, she says.
11-13-20 We need to be more careful when talking about suicide and the pandemic
AS THE world grapples with the consequences of the coronavirus pandemic, there have been widespread predictions that the fallout would lead to a rise in suicide rates. Fortunately, figures available so far suggest that this hasn’t been happening. So it is important that we now rein in this alarmist narrative to avoid creating a self-fulfilling prophecy. It is understandable that when lockdowns were first brought in, there were fears over the impact on mental health of such an extreme measure. Humans are naturally sociable, and so forcing people to reduce contact with their friends and families was always going to be difficult. Mix in fear of catching a potentially deadly virus, loss of income and less access to mental health services and it seemed like a recipe for disaster. Some commentators made predictions of a large rise in suicides, which was reported in some cases with sensationalist language. But so far, thankfully, this hasn’t been borne out. While the publishing of suicide figures normally takes many months, the initial indications for 2020 suggest that there hasn’t been a rise this year. In the Australian state of Victoria, where a very strict 16-week lockdown ended last month, recent figures show there was no difference in suicide numbers in the eight months from January to August 2020 compared with the same months in the previous year. In British Columbia, equivalent numbers seem to be slightly down on last year. Now a report has just been published online containing suicide data for three unnamed areas of England with a total population of 9 million people. Although there was a small increase from April to August 2020 compared with the previous year, the authors of the report believe that is because not all cases were recorded in 2019 as police and coroners were still getting used to the new real-time reporting system. Reassuringly, the average monthly figure for April to August 2020 was about the same as for January to March 2020. Official lockdown in England began on 23 March.
11-13-20 Bacteria found in yogurt may help bone fractures heal faster
Implants coated in bacteria could be used during bone fracture surgery to help speed healing and prevent post-operative infections. When someone suffers a fracture, surgery is sometimes needed to help it mend correctly. A common technique is to use a metal implant to help broken bones stay aligned while healing. The bone fuses to the metal as it mends. Lei Tan at Hubei University in Wuhan, China, and his colleagues tested whether coating an implant in the bacterium Lactobacillus casei, which is found in yogurt, could improve recovery. This species is known to regulate the immune environment, which could support tissue generation, and to release antibacterial substances. To do this, the researchers gave titanium implants to rats with broken tibias. Three of the rats received standard implants and three had implants coated in dead L. casei bacteria. After four weeks, the team found there was a 27 per cent increase in bone tissue in the rats with the bacteria-covered implants compared with a 16 per cent increase in rats with regular implants. An increase in bone tissue is a sign that the fracture is healing. One potential risk of implants is infection at the site where the implant meets the bone. So the team also tested if their L. Casei-treated implant was more resilient to infection by coating it in multi-drug resistant MRSA bacteria, which can cause infections. After 12 hours, the researchers found that 99.9 per cent of these pathogens were dead. Bacteria play an important role in the gut microbiome and there is increasing evidence to suggest that their benefits can be harnessed outside the gut too, says Matthew Wook Chang at the National University of Singapore.
11-13-20 Mutated strain of coronavirus 'can jump back and forth'
A new coronavirus strain could potentially leap to other animals, such as rats, mice, ferrets and voles, an expert has warned. The virus could then "come back in future years into the human population", said Sir Jeremy Farrar, director of the Wellcome Trust. His comments came amid new warnings about the virus's evolution in mink. The European Centre for Disease Prevention and Control said mink-to-human transmission could occur. And continued spread of coronavirus (Sars-CoV-2) in mink farms may eventually give rise to other mutated strains, or variants, "of concern". Further assessment was needed to assess whether mutated forms of the virus might hinder the effectiveness of treatments or vaccines, a new report concluded. Nikolaus Kriz of the European Food Safety Authority, which contributed to the report, said: "While the risk of cross-border spread of these Sars-CoV-2 variants through animals and their products is very low, it is important that people avoid close contact with farmed mink. "Additional surveillance measures are necessary to limit further spread." The risk of animals, such as mink, picking up the coronavirus and becoming a "reservoir" of infection has triggered international concern. The World Organization for Animal Health (OIE) called on countries to monitor susceptible animals, such as mink and racoon dogs, as well as humans in close contact with them, amid concern about potential public health risks. "The risk of susceptible animals, such as mink, becoming a Sars-CoV-2 reservoir generates worldwide concern, as it could pose a continued public health risk and lead to future spillover events to humans," the Paris-based organisation said in a statement. Last week, Danish scientists raised the alert over mutations found in farmed mink they said might undermine the effectiveness of Covid-19 vaccines. More than 200 people have been infected with mink-related coronavirus in Denmark, leading to a cull of millions of animals.
11-13-20 Living electrodes for linking brains to computers tested in rats
“Living electrodes” made of nerve cells genetically modified to respond to light have been successfully implanted in the brains of animals. The hope is that they will provide a better and longer-lasting way to link brains with computers than conventional electrodes. “It allows our technology to be speaking the language of the nervous system, instead of electrical jolts, which is what is done now,” says Kacy Cullen at the University of Pennsylvania. “When our implanted neurons are activated, the deeper part of the brain they are connected to then becomes activated by a natural synaptic mechanism.” Electrodes implanted in the brain have been used since the 1950s for everything from treating Parkinson’s to helping paralysed people communicate, move and even sense things. “There have been some fantastic successes,” says Cullen. But there are problems with conventional electrodes. Putting a foreign object in the brain provokes an immune response that can cause scarring, causing the performance of the electrode to change or degrade. Electrodes also affect all adjacent neurons, not just the target ones, which can lead to unwanted effects. Cullen’s approach instead relies on optogenetics: genetically modifying neurons so they respond to light signals. A clump of around 10,000 cells is then placed at the top of a dissolvable gel cylinder just twice the diameter of a human hair. The axons of the neurons – the living wires – grow along the cylinder and out the end. When 1.5-millimetre-long cylinders containing modified rat neurons were implanted in the visual cortex of rats, many of the implanted cells survived and their axons grew down into the cortex and made connections with the cells there. “If we have a problem, it’s too many connections rather than too few,” says Cullen.
11-13-20 Bolivia’s Tsimane people’s average body temperature fell half a degree in 16 years
A new study adds to evidence that 37° Celsius, or 98.6° Fahrenheit, is no longer the norm. Indigenous Bolivian Amazon dwellers are helping to bolster recent findings that normal body temperature, around 37° Celsius, or 98.6° Fahrenheit, might not be so normal anymore. The horticulturist-forager Tsimane people in the South American nation have experienced a half-degree drop, on average, in body temperatures over a decade and a half, anthropologist Michael Gurven and colleagues report October 28 in Science Advances. The new finding echoes the half-degree drop in average body temperature reported earlier this year in a Stanford University study of three U.S. population cohorts over 157 years. In that research, normal body temperature fell by 0.03° C per decade. Body temperature serves as a sort of surrogate for basal metabolic rate, or the number of calories required to keep the body working while at rest. Higher rates have been linked to shorter life spans and lower body mass. Body temperature — which also reflects circadian rhythms, immune function, the presence or absence of disease as well as ambient temperature — is affected by age, sex and time of day (SN: 10/2/17). More than a matter of curiosity, lower temperatures could be indicative of a change in basic human physiology, says Jill Waalen, an epidemiologist at the Scripps Research Translational Institute in La Jolla, Calif., who was not involved with either study. And this could mean a rethinking of what constitutes a fever — a timely question, given the use of temperature checks to screen for COVID-19. Improved lifestyles and access to medical care have reduced overall rates of infectious disease and inflammation, and could be the reason for the temperature dips. But making that link definitively has proven difficult, says Gurven, of the University of California, Santa Barbara.
11-13-20 50 years ago, scientists suspected microbes flourished in clouds
Excerpt from the November 14, 1970 issue of Science News. Clouds in the sky may contain living microbial ecosystems…. [Research] determined that metabolic activity, in the form of CO2 uptake into organic material, occurred in [airborne] dust over a 24-hour period, whereas it did not occur in sterilized control dust. The atmosphere is rich in microbial life. One census documented some 28,000 bacterial species in samples of water from clouds above a mountain in France, scientists reported in 2017. Research building over the last decade or so has supported the claim that some bacteria may indeed be metabolically active within their hazy abodes. One species of Bacillus, for example, eats sugar floating in the atmosphere to build a coating — perhaps to shield itself from ultraviolet radiation and low temperatures (SN: 2/7/15, p. 5). Some scientists suspect cloud bacteria contribute to Earth’s carbon and nitrogen cycles, and even influence weather (SN: 6/18/11, p. 12). The microbes can spur ice crystals to form, triggering rain and snow — and a ride back to Earth’s surface.
11-12-20 Pfizer covid-19 vaccine may not need to be kept at -70°C after all
There may be no need to keep the Pfizer and BioNTech coronavirus vaccine and other similar vaccines at -70°C, potentially making it much easier to distribute them across the world. Two other teams using the same messenger RNA (mRNA) technology for their vaccines have found that they remain stable for at least three months in a normal fridge. The Pfizer and BioNTech vaccine candidate generated great excitement around the world this week when the companies announced that it appears to be more than 90 per cent effective based on early results. Yet concerns were raised about the fact that the vaccine needs to be stored at between -70°C and -80°C. This is far colder than standard freezers can manage and would greatly complicate the vaccine’s storage and distribution. But two other vaccine candidates using the same mRNA technology as the Pfizer and BioNTech vaccine can be stored at higher temperatures than this. Anna Blakney at Imperial College London has told New Scientist that the vaccine candidate being developed by her team is stable for months at 4°C, the same temperature as a standard fridge. Another vaccine candidate developed by CureVac in Tübingen, Germany, remains stable for at least three months when stored at a standard refrigerator temperature, the company announced on 12 November. The same should be true for the Pfizer and BioNTech vaccine, says Blakney. “I guarantee that they are doing the exact same studies.” The mRNA vaccines consist of strands of RNA that code for the coronavirus spike protein, a key part of the virus that allows it to infect humans. When the RNAs from the vaccine enter human cells, the cells start making the spike protein, prompting an immune response without an infection. Naked RNAs – those without anything protecting them – would be rapidly chewed up by enzymes in the blood. In the vaccines, they are packaged in tiny droplets of fat, called lipid nanoparticles or LNPs, which protect them and help them get into cells.
11-11-20 The covid-19 pandemic has reignited questions about population size
A pandemic assisted by our incursions into nature has given questions about human population size a renewed focus, but advocates for limiting population also have questions to answer. LETTERS to New Scientist in response to coverage of environmental issues often raise a glaring omission: why aren’t we mentioning the elephant in the room, namely the number of humans on the planet? A pandemic assisted by our incursions into nature has now given questions about human population size a renewed focus. Such questions have been hugely contentious since at least 1798, when Thomas Malthus issued the dire warnings that still set the tenor of the debate in An Essay on the Principle of Population. See The great Population debate: Are there to many people on the planet? where you will find our analysis of where that debate stands today. While longer-term reductions in human numbers can only be good for the planet, those who advocate limiting population as an environmental panacea must answer two outstanding questions. The first is what they propose we do to reduce our impact as we grapple with the climate emergency in the crucial coming years, given that efforts to reduce population necessarily play out over decades. The second is what tools they propose we use to reduce our headcount. We know what works to limit population growth without resorting to brutal and disastrous coercion. It is broadly what the world has been doing for the past half century, albeit often in the face of significant opposition: assisting the economic development of those, mainly poorer, countries with high population growth, broadening access to education, especially for girls and women, and ensuring access to contraception and abortion. There are worrying signs that the pandemic, by limiting access to family planning, has increased birth rates in some lower-income countries, reversing a decades-long downwards trend. Access to education has also been hit.
11-11-20 Paul Ehrlich: There are too many super-consumers on the planet
Conservation biologist Paul Ehrlich raised fears about our rapidly growing population in his 1968 book The Population Bomb. Fifty years later, he reflects on what has changed. IN THE late 1960s, the nascent environmental movement began to worry about humanity’s impact on the planet, and the idea that population growth needed to be limited became a mainstream talking point. Paul Ehrlich was at the centre of that movement from the beginning. In 1968, together with his wife Anne, he wrote an influential book, The Population Bomb, which crystallised fears about the planet’s burgeoning population. It predicted widespread famine, societal upheaval and a deterioration in environmental conditions in the 1970s if steps were not taken – and fast – to both stop population growing and reduce it. Ehrlich was wrong. The “green revolution” that vastly increased agricultural production starting in the 1960s meant his dire predictions largely didn’t come to pass. His work has since been accused of alarmism, and of helping to spread fears of rising birth rates in lower-income countries that provided justification for compulsory population control measures. In fact, as he now acknowledges, consumption in higher-income countries is an indispensable factor in the equation. In light of our worsening climate crisis, in the past two years debate over population size has started re-entering the mainstream. Now 88, Ehrlich is still active at Stanford in the field of population studies. New Scientist caught up with him to ask: does he recant any of his earlier views? Paul Ehrlich: The main problem we have with all our environmental dilemmas is too much consumption. Humans are just using too much of what there is and using more all the time. To say that the aggregate consumption is just a problem of overconsumption is like saying that the area of a rectangle is it’s too wide; it has nothing to do with length. The number of people and how much each one consumes multiply together to give you your aggregate consumption.
11-11-20 The population debate: Are there too many people on the planet?
The world population is 7.7 billion. What do our growing numbers mean for economic security, climate change, environmental destruction and the likelihood of pandemics? IN THE once-seedy district of Soho, about 10 minutes’ walk from New Scientist‘s London offices, a pump, a plaque and a pub commemorate one of the greatest ever breakthroughs in human history: a decisive step made almost 200 years ago towards conquering infectious disease. Our current global health crisis is a reminder of how little we want to return to the days when deadly infections carried away most of us. Yet also in some way, advances back then were a first step on a path towards planetary perdition. The success against infectious disease, alongside other major developments, dramatically improved our survival and set humanity’s numbers soaring, from little more than 1.25 billion people back then to 7.7 billion now. Now, climate change, biodiversity loss, the degradation of the biosphere and, yes, coronavirus are forcing us to consider the legacy of that success. The pandemic is becoming the latest focus for an old, uniquely contentious question: are there just too many of us on the planet? The basic argument is hard to deny. With fewer of us around, there would be fewer greenhouse gas emissions, less pollution and waste, more space for both us and the rest of the natural world to survive and thrive. So let’s bite the bullet. Let’s talk about population – where it is heading globally, what that means for the planet, and what, if anything, we should be doing to limit its growth. Be warned, however: finding answers isn’t nearly as easy as posing questions. And with scenes of sexism, racism, nationalism, misogyny and eugenics, what follows at times makes for uncomfortable viewing.o
11-11-20 Evolution explains why social distancing due to covid-19 is so hard
Hugs, handshakes and air kisses serve the same crucial purposes as animal greetings like sniffing, eye poking and buttock grabbing. ON 9 MARCH, Mark Rutte, the Dutch prime minister, called a press conference to discuss his country’s response to the covid-19 pandemic. “From now on, we stop shaking hands,” he declared – before promptly reaching out his hand to greet an expert on infectious diseases. Many of us can empathise. Social distancing sounds innocuous, but this year we have discovered how hard it can be in practice. Touchy-feely greetings, such as handshakes, hugs, kisses and nose rubbing, are deeply embedded in many cultures. These gestures aren’t merely learned, however. Look to the animal kingdom and you will see that many species – especially highly social ones – perform physical rituals when they approach each other. If our urges to touch one another in greeting seem instinctual, it is because they are. Greetings adopted by animals can be very different to our own – they include eye poking and other gestures that might make you squirm – but understanding these behaviours can give us an insight into human salutations. Examining the evolution of greetings throws light on the subtle ways they lubricate social interactions and also helps to explain why they are so diverse. As we are a super-social species, it isn’t surprising that many of us are struggling to adjust to the new normal. But the good news is that we are proven masters at adapting our greetings to fit new situations. Mammals tend to use scents to suss each other out, which explains why their greetings are so intimate. A new encounter often entails sniffing another individual’s face, flanks and genitals for volatile chemicals that reflect its hormonal state. This offers cues about strength and fertility, allowing animals to size up potential opponents and mates.
11-11-20 The population debate: Are there too many people on the planet?
The world population is 7.7 billion. What do our growing numbers mean for economic security, climate change, environmental destruction and the likelihood of pandemics? IN THE once-seedy district of Soho, about 10 minutes’ walk from New Scientist‘s London offices, a pump, a plaque and a pub commemorate one of the greatest ever breakthroughs in human history: a decisive step made almost 200 years ago towards conquering infectious disease. Our current global health crisis is a reminder of how little we want to return to the days when deadly infections carried away most of us. Yet also in some way, advances back then were a first step on a path towards planetary perdition. The success against infectious disease, alongside other major developments, dramatically improved our survival and set humanity’s numbers soaring, from little more than 1.25 billion people back then to 7.7 billion now. Now, climate change, biodiversity loss, the degradation of the biosphere and, yes, coronavirus are forcing us to consider the legacy of that success. The pandemic is becoming the latest focus for an old, uniquely contentious question: are there just too many of us on the planet? The basic argument is hard to deny. With fewer of us around, there would be fewer greenhouse gas emissions, less pollution and waste, more space for both us and the rest of the natural world to survive and thrive. So let’s bite the bullet. Let’s talk about population – where it is heading globally, what that means for the planet, and what, if anything, we should be doing to limit its growth. Be warned, however: finding answers isn’t nearly as easy as posing questions. And with scenes of sexism, racism, nationalism, misogyny and eugenics, what follows at times makes for uncomfortable viewing.
11-11-20 Protecting the brain from infection may start with a gut reaction
In mice, immune cells on the brain’s surface are first trained in the intestines to recognize invaders. Some immune defenses of the brain may have their roots in the gut. A new study in mice finds that immune cells are first trained in the gut to recognize and launch attacks on pathogens, and then migrate to the brain’s surface to protect it, researchers report online November 4 in Nature. These cells were also found in surgically removed parts of human brains. Every minute, around 750 milliliters of blood flow through the brain, giving bacteria, viruses or other blood-borne pathogens an opportunity to infect the organ. For the most part, the invaders are kept out by three membrane layers, called the meninges, which wrap around the brain and spinal cord and act as a physical barrier. If a pathogen does manage to breach that barrier, the researchers say, the immune cells trained in the gut are ready to attack by producing a battalion of antibodies. The most common route for a pathogen to end up in the bloodstream is from the gut. “So, it makes perfect sense for these [immune cells] to be educated, trained and selected to recognize things that are present in the gut,” says Menna Clatworthy, an immunologist at the University of Cambridge. Clatworthy’s team found antibody-producing plasma cells in the leathery meninges, which lie between the brain and skull, in both mice and humans. These immune cells produced a class of antibodies called immunoglobulin A, or IgA. These cells and antibodies are mainly found in the inner lining of the gut and lungs, so the scientists wondered if the cells on the brain had any link to the gut. It turned out that there was: Germ-free mice, which had no microbes in their guts, didn’t have any plasma cells in their meninges either. However, when bacteria from the poop of other mice and humans were transplanted into the mice’s intestines, their gut microbiomes were restored, and the plasma cells then appeared in the meninges.
11-11-20 Giant seal fossil found in New Zealand hints they evolved in the south
The discovery of an extinct species of monk seal, which lived 3 million years ago, overturns what we previously knew about how seals evolved. James Rule at Monash University in Melbourne, Australia, and his colleagues identified the new species while examining fossil specimens that had been found on beaches in South Taranaki, on the west coast of New Zealand’s North Island. It has been named Eomonachus belegaerensis, after the fictional Belegaer sea from J.R.R. Tolkien’s Lord of the Rings. Seven fossils, including a complete skull, were found between 2009 and 2016 by members of the public. They are the oldest evidence of monk seals ever discovered. The fossils suggest that this species was approximately 2.5 metres long when fully grown, and weighed 200 to 250 kilograms. Based on its teeth, the seal’s diet was probably similar to that of living monk seals, consisting of fish, squid and octopus, says Rule. The discovery overturns accepted knowledge about how true seals – which are earless and a distinct group from fur seals and sea lions – evolved. “It was previously thought that all [true] seals, including monk seals and the Antarctic seals, originated in the North Atlantic Ocean,” says Rule. “That’s where most of the fossils of seals have been found.” Scientists had believed that these seals then crossed the equator to populate the southern hemisphere. But the discovery of E. belegaerensis in New Zealand suggests that the ancestors of living Antarctic, elephant and monk seals actually evolved in the southern hemisphere. The researchers incorporated the new discovery into an analysis of the distribution of living and extinct seals globally over time. They concluded that many seals may have instead evolved in the southern Pacific and crossed the equator up to eight times.
11-11-20 Lizards that lost their legs re-evolved them as the climate got wetter
In the distant past, climate change may have driven limbless lizards to evolve legs – having already lost them once before. The once-four-legged, ancient lizards of the Brachymeles genus first emerged in a dry environment in modern-day South-East Asia. They dropped all four limbs about 62 million years ago, but around 40 million years later, some species grew them back, says Philip Bergmann at Clark University in Worcester, Massachusetts. “Around the time that these lizards went from snake-like to re-evolving limbs, there was this climate shift from an environment that’s much drier than it is today, to this ever-wet monsoonal climate where you essentially have rainfall all year round,” says Bergmann. Growing limbs back probably helped these burrowing animals dig into the wetter, more packed ground, he says. Modern Brachymeles skinks (not to be confused with snakes) include species ranging from no limbs, to small limbs with one or two digits, to full limbs with five fingers and five toes. The “snake-like” forms are longer with more vertebrae, but the species that re-evolved limbs also lost some of those vertebrae, becoming shorter. Bergmann and his colleagues captured and carried out precise measurements on nearly 150 wild lizards representing 13 different species of modern Brachymeles in the Philippines and Thailand. They then subjected them to various running and burrowing tests over different soils. They found that the more snake-like the lizards were, the less force they used to push into the soil with their heads, which were narrower. By contrast, legged lizards dug into the soil with their limbs, using greater force – an ability that probably helps them live in wetter environments where soil has four times greater resistance compared with dry, loose soil.
11-11-20 Animals infected with covid-19 could undo efforts to stop the pandemic
Mink are the latest animal to be infected with covid-19, risking the prospect of a dangerous mutation that could pass back to humans. While the threat is small, there are many reasons that animals catching the coronavirus is bad news. ALL 17 million farmed mink in Denmark were put at risk of being slaughtered last week after the discovery that mutant forms of the coronavirus are spreading among the animals. The virus has already spread back to humans. Some reports suggest that at least one of the mutations makes the virus more dangerous, although the idea is highly disputed, and claims that it could hamper the development of a vaccine don’t yet stand up to scrutiny. The call for culling has now been dropped, but the human-mink-human transmission chain demonstrates the real and present danger of what virologists call “reverse spillover” and “spillback”. The pandemic began with spillover of SARS-CoV-2, the virus that causes covid-19, from wildlife to humans. Reverse spillover means transmission from humans back into animals, both wild and domesticated. Spillback completes the circle, with the virus jumping back into humans again. This cyclical transmission represents a threat to both wildlife and humans. “The risk of SARS-CoV-2 infecting novel wild species is concerning enough to warrant preventative measures,” says Alison Peel of the Griffith Wildlife Disease Ecology Group at Griffith University in Queensland, Australia. Anyone who is at risk of coming into close contact with wild animals should take precautions, she and others say: wear a mask, wash your hands and keep your distance. SARS-CoV-2 is known to be a highly promiscuous virus. Research into its origins strongly suggests that it started life in horseshoe bats and may have passed through an intermediate host, possibly Malayan pangolins, en route to humans.
11-10-20 Pfizer covid-19 vaccine will need a gigantic new network of freezers
We have a covid-19 vaccine that works. But can we keep it cold enough to get it to enough people? Among Pfizer and BioNTech’s long list of risks and uncertainties for its BNT162b2 vaccine, which this week was reported to be 90 per cent effective, is the challenge of its “ultra-low temperature formulation”, and how to store and distribute it along the so-called “cold chain”. Between manufacture and doses being given to people, the vaccine needs to be kept frozen at about -70°C, around four times colder than a home freezer can manage. Once it has left Pfizer’s manufacturing facilities in Kalamazoo, Michigan, and Puurs, Belgium, the vaccine cannot be thawed and frozen more than four times in transit, according to UK health secretary Matt Hancock. He said that adds “another tricksiness” to logistics. The vaccine, developed using a new approach of using messenger RNA from the coronavirus, is unusual in needing such low temperatures. Most vaccines are refrigerated at around 2-8°C, rather than frozen. Even those that are frozen, such as the Varivax vaccine used against the virus that causes chickenpox, are stored at much higher temperatures than Pfizer’s one. Nilay Shah at Imperial College London says healthcare systems have some experience of handling cells and samples at temperatures at around -70°C. However, he says it is “not at the volumes we anticipate for vaccines”. Pfizer told New Scientist it is confident it can distribute the vaccine at such low temperatures. Vials of the vaccine will be put in purpose-built packaging about the size of an aircraft carry-on suitcase, weighing around 32 kilograms. Dry ice will be used inside to keep temperatures at -75°C, give or take 15°C, for up to 10 days. The dry ice (solid carbon dioxide) will be replenished along the journey. One trade body has already said there is enough capacity to supply that dry ice, at least in the US and Canada.
11-10-20 What's the science behind mink and coronavirus?
Mutations in coronavirus have triggered culls of millions of farmed mink in Denmark. Part of the country has been put under lockdown after Danish authorities found genetic changes they say might undermine the effectiveness of future Covid-19 vaccines. More than 200 people have been infected with mink-related coronavirus. And the UK has imposed an immediate ban on all visitors from Denmark amid concerns about the new strain. Danish scientists are particularly concerned about one mink-related strain of the virus, found in 12 people, which they say is less sensitive to protective antibodies, raising concerns about vaccine development. The World Health Organization has said the reports are concerning, but further studies are needed to understand the implications for treatments and vaccines. "We need to wait and see what the implications are but I don't think we should come to any conclusions about whether this particular mutation is going to impact vaccine efficacy," said chief scientist, Soumya Swaminathan. The coronavirus, like all viruses, mutates over time and there is no evidence that any of the mutations found in Denmark pose an increased danger to people. Dr Marisa Peyre, an epidemiologist from the French research institute Cirad, said the development was "worrying", but we don't yet know the full picture. "Every time the virus spreads between animals it changes, and if it changes too much from the one that is circulating within humans at the moment, that might mean that any vaccine or treatment that will be produced soon might not work as well as it should do," she explained. This is a very unusual chain of events: a virus that originally came from a wild animal, probably a bat, jumped into humans, possibly via an unknown animal host, sparking a pandemic. Mink kept in large numbers on mink farms have caught the virus from infected workers. And, in a small number of cases, the virus has "spilled back" from mink to humans, picking up genetic changes on the way. Mutations in some mink-related strains involve the spike protein of the virus, which is targeted by some vaccines being developed.
11-10-20 'Mutant coronavirus' seen before on mink farms, say scientists
A mutant form of coronavirus found in Denmark has arisen previously in mink, scientists have revealed. The mutated virus, which appears to have spread from animals to humans in Denmark, has been detected retrospectively at a mink farm in the Netherlands, according to a leading Dutch expert. The mink were culled and the mutated strain did not infect humans, he said. Six countries have reported coronavirus outbreaks at mink farms. They include the Netherlands, Denmark, Spain, Sweden, Italy and the US. Mink are known to be susceptible to Sars-CoV-2, the virus that causes Covid-19, which can spread rapidly from animal to animal in conditions where thousands of animals are kept in close proximity. The farmed weasel-like animals have become infected by farm workers during the pandemic, and have occasionally passed the virus on to humans, raising the risk of the virus acquiring mutations. Danish scientists are worried that genetic changes in a mink-related form of the virus, infecting a dozen people, has the potential to make future vaccines less effective. The genetic change is in the spike protein of the virus, which is important in the body's immune response, and a key target for vaccines. The Danish genome sequences were recently released on a public database, allowing scientists in other countries to search for evidence of the mutation. Prof Wim van der Poel, a veterinary expert at Wageningen University, said analysis of genetic data from the Netherlands revealed one previous case of the mutation at a mink farm in early May. He told BBC News: "We have once seen a mutant virus with a comparable mutation in the spike protein encoding region, in mink in the Netherlands, but this mutant did not spread to humans and the mink of the involved farm were culled." The Netherlands launched a widespread cull of mink after signs, in a small number of cases, that humans had picked up coronavirus from mink.
11-10-20 Two-million-year-old skull of human 'cousin' unearthed
Australian researchers say the discovery of a two-million-year-old skull in South Africa throws more light on human evolution. The skull was a male Paranthropus robustus, a "cousin species" to Homo erectus - a species thought to be direct ancestors of modern humans. The two species lived around the same time, but Paranthropus robustus died out earlier. The research team described the find as exciting. "Most of the fossil record is just a single tooth here and there so to have something like this is very rare, very lucky," Dr Angeline Leece told the BBC. The researchers, from Melbourne's La Trobe University, found the skull's fragments in 2018 at the Drimolen archaeological site north of Johannesburg. It was uncovered just metres away from a spot where a similarly aged Homo erectus skull of a child was discovered in 2015. Archaeologists then spent the past few years piecing together and analysing the fossil. Their findings were published in the Nature, Ecology and Evolution journal on Tuesday. Co-researcher Jesse Martin told the BBC that handling the fossil pieces was like working with "wet cardboard", adding he had used plastic straws to suck the last traces of dirt off them. It is thought that three hominins (human-like creatures) species lived in South Africa at the same time in competition with each other. As such the skull discovery presented a rare example of "microevolution" within human lineage, Mr Martin said. Paranthropus robustus had large teeth and small brains, differing from Homo erectus which had large brains and small teeth. It is believed the former's diet involved eating mainly tough plants, like tubers and bark. "Through time, Paranthropus robustus likely evolved to generate and withstand higher forces produced during biting and chewing food that was hard or mechanically challenging to process with their jaws and teeth," said Dr Leece. The scientists said it was possible that a wetter environment caused by climate change may have reduced the food available to them.
11-9-20 'Mutant coronavirus' seen before on mink farms, say scientists
A mutant form of coronavirus found in Danish mink has arisen before, scientists have revealed. The mutated virus, which appears to have spread from animals to humans in Denmark, has been detected retrospectively at a mink farm in the Netherlands, according to a leading Dutch expert. The mink were culled and the mutation did not infect humans there, he said. Six countries have reported coronavirus outbreaks at mink farms. They include the Netherlands, Denmark, Spain, Sweden, Italy and the US. Danish scientists believe the mutations are concerning because of their potential to make vaccines less effective. The government has ordered all farmed mink to be killed due to concerns a dozen people have been infected. The genetic change is in a part of the Sars-CoV-2 virus known as the spike protein, which is important in immunity, and a target for some future vaccines and treatments. The Danish genome sequences were recently released on a public database, allowing scientists in other countries to look for evidence of the mutation. Prof Wim van der Poel, a veterinary expert at Wageningen University, said analysis of genetic data from the Netherlands revealed one previous case of the mutation at a mink farm there. He told BBC News: "We have once seen a mutant virus with a comparable mutation in the spike protein encoding region, in mink in the Netherlands, but this mutant did not spread to humans and the mink of the involved farm were culled." The Netherlands launched a widespread cull of mink after signs, in a small number of cases, that humans had picked up coronavirus from mink. The genetic data from Denmark was released on an international database a few days ago, with some scientists questioning why it had not been released sooner. "I think that it is most disappointing that the data have only just reached the light of day," said Prof James Wood, head of the department of veterinary medicine at the University of Cambridge, UK. He said the genetic changes needed careful evaluation, as reports from Denmark suggested an effect on immunity. "This may be what triggered the enhanced quarantine measures for travellers from Denmark. But far more careful evaluation is urgently needed." Mink farming required "enhanced biosecurity (or suspension) at this time", he added.
11-9-20 Penicillin allergies may be linked to one immune system gene
People with self-reported allergies to the drug may have a vulnerability on the HLA-B gene. Penicillin, effective against many bacterial infections, is often a first-line antibiotic. Yet it is also one of the most common causes of drug allergies. Around 10 percent of people say they’ve had an allergic reaction to penicillin, according to the U.S. Centers for Disease Control and Prevention. Now researchers have found a genetic link to the hypersensitivity, which, while rarely fatal, can cause hives, wheezing, arrythmias and more. People who report penicillin allergies can have a genetic variation on an immune system gene that helps the body distinguish between our own cells and harmful bacteria and viruses. That hot spot is on the major histocompatibility complex gene HLA-B, said Kristi Krebs, a pharmacogenomics researcher for the Estonian Genome Center at the University of Tartu. She presented the finding October 26 at the American Society of Human Genetics 2020 virtual meeting. The research was also published online October 1 in the American Journal of Human Genetics. Several recent studies have connected distinct differences in HLA genes to bad reactions to specific drugs. For example, studies have linked an HLA-B variant to adverse reactions to an HIV/AIDS medication called abacavir, and they’ve linked a different HLA-B variant to allergic reactions to the gout medicine allopurinol. “So it’s understandable that this group of HLA variants can predispose us to higher risk of allergic drug reactions,” says Bernardo Sousa-Pinto, a researcher in drug allergies and evidence synthesis at the University of Porto in Portugal, who was not involved in the study. For the penicillin study, the team hunted through more than 600,000 electronic health records that included genetic information for people who self-reported penicillin allergies. The researchers used several genetic search tools, which comb through DNA in search of genetic variations that may be linked to a health problem. Their search turned up a specific spot on chromosome 6, on a variant called HLA-B*55:01.
11-7-20 FDA advisory panel declines to support a controversial Alzheimer’s treatment
The drug, aducanumab, is made by pharmaceutical company Biogen. The fate of a potential new Alzheimer’s drug is still uncertain. Evidence that the drug works isn’t convincing enough for it to be approved, outside experts told the U.S. Food and Drug Administration during a Nov. 6 virtual meeting that at times became contentious. The scientists and clinicians were convened at the request of the FDA to review the evidence for aducanumab, a drug that targets a protein called amyloid-beta that accumulates in the brains of people with Alzheimer’s. The drug is designed to stick to A-beta and stop it from forming larger, more dangerous clumps. That could slow the disease’s progression but not stop or reverse it. When asked whether a key clinical study provided strong evidence that the drug effectively treated Alzheimer’s, eight of 11 experts voted no. One expert voted yes, and two were uncertain. The FDA is not bound to follow the recommendations of the guidance committee, though it has historically done so. If ultimately approved, the drug would be a milestone, says neurologist and neuroscientist Arjun Masurkar of New York University Langone’s Alzheimer’s Disease Research Center. Aducanumab “would be the first therapy that actually targets the underlying disease itself and slows progression.” Developed by the pharmaceutical company Biogen, which is based in Cambridge, Mass., the drug is controversial. That’s because two large clinical trials of aducanumab have yielded different outcomes, one positive and one negative (SN: 12/5/19). The trials were also paused at one point, based on analyses that suggested the drug didn’t work. Those unusual circumstances created gaps in the evidence, leaving big questions in some scientists’ minds about whether the drug is effective. Aducanumab’s ability to treat Alzheimer’s “cannot be proven by clinical trials with divergent outcomes,” researchers wrote in a perspective article published November 1 in Alzheimer’s & Dementia. The drug should be tested again with a different clinical trial, those researchers say.
11-7-20 What's the science behind mink and coronavirus?
Mutations in coronavirus have triggered culls of millions of mink across Denmark. Part of the country has been put under lockdown after Danish authorities found genetic changes they say might undermine the effectiveness of future Covid-19 vaccines. More than 200 people have been infected with strains related to mink, according to reports. The World Health Organization has said it is too early to jump to conclusions. "We need to wait and see what the implications are but I don't think we should come to any conclusions about whether this particular mutation is going to impact vaccine efficacy," said chief scientist, Soumya Swaminathan. The coronavirus, like all viruses, mutates over time and there is no evidence that any of the mutations found in Denmark pose an increased danger to people. Danish scientists are particularly concerned about one mink-related strain, found in 12 people, which they say is less sensitive to antibodies against the virus, raising concerns about vaccine development. The UK has imposed an immediate ban on all visitors from Denmark amid concerns about the new strain. Dr Marisa Peyre, an epidemiologist from the French research institute Cirad, said the development was "worrying", but we don't yet know the full picture. "Every time the virus spreads between animals it changes, and if it changes too much from the one that is circulating within humans at the moment, that might mean that any vaccine or treatment that will be produced soon might not work as well as it should do," she explained. This is a very unusual chain of events: a virus that originally came from a wild animal, probably a bat, jumped into humans, possibly via an unknown animal host, sparking a pandemic. Mink kept in large numbers on mink farms have caught the virus from infected workers. And, in a small number of cases, the virus has "spilled back" from mink to humans, picking up genetic changes on the way.
11-6-20 Poor diet: Children 20cm shorter as a result, analysis says
Poor diets for school-age children may contribute to an average height gap of 20cm (7.9in) between the tallest and shortest nations, an analysis suggests. It reports that in 2019 the tallest 19-year-old boys lived in the Netherlands (183.8cm or 6ft) and the shortest lived in Timor Leste (160.1cm or 5ft 3in). Meanwhile the UK's global height ranking fell, with 19-year-old boys being 39th tallest in 2019 (1.78m or 5ft 10in) from 28th tallest in 1985. The study appears in The Lancet. Researchers say tracking changes in the height and weight of children across the world and over time is important because they can reflect the quality of nutrition available, and how healthy environments are for young people. The team analysed data from more than 65 million children and adolescents aged 5 to 19 years from more than 2000 studies between 1985 and 2019. They found that in 2019, on average, children and teenagers in north-western and central Europe (eg those in the Netherlands and Montenegro) were the tallest in the world. Meanwhile, the 19-year-olds who were on average the shortest lived in South and South-East Asia, Latin America and East Africa. The study also looked at children's BMI, a measure that helps indicate whether a person is a healthy weight for their height. Researchers found older teenagers with the largest BMI lived in the Pacific Islands, Middle East, USA and New Zealand. Meanwhile 19-year-olds with the lowest BMI lived in South Asian countries such as India and Bangladesh. The researchers estimate broadly that the difference between countries with the lowest and highest BMIs in the study was equivalent to about 25kg (55lb). In some countries children reached a healthy BMI at the age of five, but were likely to become overweight by the time they were 19. While researchers acknowledge that genetics play an important part in individual children's height and weight, they say when it comes to the health of entire populations, nutrition and the environment are key. They also argue that global nutrition policies overwhelmingly focus on under-fives, but suggest their study shows more attention needs to be paid to the growth patterns of older children.
11-6-20 An ancient amphibian is the oldest known animal with a slingshot tongue
A newly described species dubbed Yaksha perettii lived 99 million years ago. A tiny amphibian that lived 99 million years ago had a secret weapon: A tongue that shot out of its mouth like a bullet to snatch its prey. It’s the earliest known example of this “ballistic tongue” style of predation, researchers say. The amphibian is a new species, represented by a few tiny bits of skeleton and soft tissue discovered in chunks of Myanmar amber. The centerpiece of these finds is a newly discovered complete skull, exquisitely preserved in 3-D, that includes a long thin bone connected to the creature’s neck, with some remnants of tongue attached to the end. The creature, which measured just 52 millimeters long from snout to pelvis (not including a tail), used this bone to shoot its tongue out of its mouth and catch prey. This “sit-and-wait” style of predation is similar to that of a modern chameleon, researchers report in the Nov. 6 Science. Led by paleontologist Juan Daza of Sam Houston State University in Huntsville, Texas, the team dubbed the creature Yaksha perettii. “Yaksha” is a type of nature spirit in Myanmar folklore, thought to protect the roots of trees, and “perettii” is in honor of Swiss mineralogist Adolf Peretti, who discovered the fossil. Y. perettii has a lot in common with chameleons, including its scaly skin and tongue-flicking feeding style, Daza says. In fact, in a previous study, he and Edward Stanley of the Florida Museum of Natural History in Gainesville described a separate fossil, also preserved in amber, of what they now know to be a juvenile Y. peretti as one of those reptiles. At the time, “we agreed that it was a chameleon,” says Stanley, who is also a coauthor on the new study. Then paleontologist Susan Evans of University College London stepped in. The creature was not a reptile at all, she said: It was an albanerpetontid, an extinct group of weird amphibians that Evans has been studying for decades. Albanerpetontids first appear in the fossil record as far back as 165 million years ago and were last found in rocks dating to just a million years ago.
11-6-20 We may finally have figured out which group of animals evolved first
Sponge or jelly? Though it sounds like a choice between desserts, it turns out that either sponges or comb jellies are the key to understanding the origin of animals, what the first animals were like and when the first brains evolved. That is because one of them was the first animal group to split from other animals and begin evolving separately – but it has long been unclear which. A new analysis points the finger at jellies. The study has been praised by scientists on both sides of the debate because it brings clarity to a confused area, but it isn’t being interpreted as the definitive answer. The first complex animals evolved around 600 million years ago. Unlike their simpler ancestors, they had large bodies made of many cells, which developed into specialised organs. That ancestral population gave rise to all the major animal groups, from starfish and insects to birds and mammals, but we don’t know what the first animals looked like or how they behaved. It would help to know the order in which the different animal groups split from each other, but this is contentious. It comes down to the two groups that are known to be older than the rest: comb jellies, also known as ctenophores, and sponges. Sponges live stationary lives in the sea and have no nervous systems, while comb jellies superficially look like jellyfish and do have nervous systems. “The ancestor of animals I can definitely say was neither a ctenophore nor a sponge as we see them today,” says Antonis Rokas at Vanderbilt University in Tennessee. But their DNA can tell us which genes were present in the first animals, revealing what those first animals were like. For many decades, it was assumed that sponges were the first to split and were therefore the oldest and most primitive animals.
11-5-20 America is clearly headed for the decriminalization of all drugs
Americans are deeply divided on who should be president. But we are increasingly united on drug policy, and the undeniable trend — with rising support across state, partisan, and other demographic lines — is toward decriminalization and perhaps even eventual legalization of all drugs. Consider the results from a handful of drug-related ballot measures this week. Arizona, Mississippi, Montana, New Jersey, and South Dakota voted on marijuana questions, with all but Mississippi considering legalization for recreational use (or amending the state constitution to allow the legislature to take up that issue). Every single measure passed, and not one was a close vote. In deep red South Dakota, where President Trump won with more than 60 percent of votes cast, a medical marijuana program was approved by seven in 10 voters and recreational legalization by a comfortable seven-point margin (as of this writing). More remarkable are the ballot initiatives that weren't about weed. Washington, D.C., enthusiastically approved a measure functionally decriminalizing psychedelic mushrooms. Oregon voters endorsed creating a program for the same mushrooms' medically supervised use, and they also voted to decriminalize personal (i.e., quantity-limited) possession of hard drugs, including cocaine, heroin, LSD, and meth. Oregon deserves special attention here, because it's been a bellwether on drug laws for a century. In 1923, Oregon was among the earliest states to ban marijuana, doing so with neighbors California and Washington more than a decade before recreational marijuana use was effectively prohibited by federal tax law in 1937. Medical marijuana was banned at the federal level by 1970's Controlled Substances Act, which declared the drug war as we know it today: utterly ineffective, often counterproductive, incredibly expensive, and a moral monstrosity. By then, however, change was already afoot in Oregon. Just three years later, in 1973, Oregon became the first state to decriminalize pot. Five other states — Alaska, California, Colorado, Maine, and Ohio — followed suit within two years. Oregon was also an early adopter in permitting medical marijuana use, legalizing it in 1998, only two years after the first such measure passed in California. In 2014, Oregon legalized recreational use, again just two years behind the first states to do so (Colorado and Washington State in 2012). Now, in 2020, Oregon is both the first state to legalize the psychedelic ingredient in "magic mushrooms" and the first to decriminalize harder drugs. It's an outlier, but if historical patterns hold, it won't be for long. Notice that Oregon's big drug law changes tend to happen within the first decade of a broader national shift; that they tend to be grouped with similar moves from other West Coast and Mountain West states; and that they are happening at an accelerating pace. For marijuana, this has meant that both early prohibitions and early decriminalization and legalization laws popped up in clusters on the western edge of the country before jumping to New England (usually Maine and/or Massachusetts) then gradually moving into the Midwest and South.
11-5-20 Female big-game hunters may have been surprisingly common in the ancient Americas
A woman buried 9,000 years ago with her hunting toolkit is shedding new light on gender roles. A woman buried with spearpoints and other hunting tools roughly 9,000 years ago in Peru’s Andes Mountains has reemerged to claim the title of the oldest known female big-game hunter in the Americas. Her discovery led researchers to conclude that, among ancient Americans, nearly as many females as males hunted large animals — a finding that is challenging long-standing ideas about ancient gender roles. Modern and recent hunter-gatherer societies emphasize males hunting. But in mobile groups that inhabited the Americas thousands of years ago, up to half of big-game hunters were women, archaeologist Randall Haas of the University of California, Davis and colleagues report November 4 in Science Advances. Until now, many researchers have regarded stones sharpened to a point and other typical hunting items placed in ancient women’s graves as cutting or scraping tools. The dominance of male hunters in modern hunter-gatherer populations has fueled a tendency to, in essence, give ancient men the spearpoint and ancient women the short end of the stick. “It is time to stop thinking of [ancient] female large-game hunters as outliers,” says archaeologist Ashley Smallwood of the University of Louisville in Kentucky. Gender roles in modern hunter-gatherer groups can’t be assumed to apply to those that lived long ago, Smallwood says. While much remains unknown about gender roles in ancient hunter-gatherer groups, Haas’ view began to take shape in 2018. His team, collaborating with members of a local community at a high-altitude site in southern Peru called Wilamaya Patjxa, unearthed five human burial pits containing six individuals. One pit held a 17- to 19-year-old young woman who had been buried with a set of stone tools for big-game hunting. Her toolkit included four spearpoints that would have been attached to shafts and likely hurled at prey using hand-held spear throwers. Other stone implements, and a pigment chunk, buried with her were probably used to cut apart game, extract bone marrow or scrape hides and perform detailed hide work and hide tanning.
11-4-20 Men and women in early Americas shared hunting duties equally
A young woman buried with stone tools including spearheads 9000 years ago in what is now Peru probably hunted deer and wild camels. The finding may help overturn long-standing assumptions about gender roles in ancient hunter-gatherer communities in the Americas. Within present-day hunter-gatherer communities across North and South America, women make up at least one-third of the hunting force, and possibly as much as half, says Randy Haas at the University of California, Davis. However, although archaeological investigations over the past century have also found hunting tools in the graves of prehistoric women throughout the Americas, Haas says it took the unearthing of a young woman’s bones in the Andes mountains for scientists to set aside their unconscious biases about gender roles and recognise what they were seeing. “There is sexist ideology in Western culture that may have slowed our ability to recognise females as hunters in the past,” says Haas, adding that he himself was “surprised, unfortunately” by his discovery. “Even some of the most forward-thinking feminist scholars had accepted it to be true [that women weren’t usually hunters],” he says. Haas and his colleagues recently ran carbon dating and protein analyses on bones and teeth found less than a metre underground in a burial pit discovered in southern Peru in 2018. Their results provided “solid” confirmation that the human remains belonged to a 17 to 19-year-old woman who was interred between 8700 and 9000 years ago with a 24-piece hunting toolkit including spearhead points, butcher knives and tanning blades. The butchered remains of deer and camels at the site hint at the animals she hunted. Rather than assuming the teenager was a one-off case of a female hunter, Haas checked the scientific archives for other published discoveries of humans buried with hunting tools anywhere “from Alaska to Argentina” at least 8000 years ago. Of the 27 burials he identified, nearly half recorded the gender of the buried individual as female, he says.
11-4-20 Coronavirus rules for care homes are too strict and not science-based
Rules for care homes to prevent the spread of coronavirus are too strict and not based on science – this could cost lives, says June Andrews. Restrictions to stop the spread of coronavirus are tightening across the UK, including a four-week lockdown in England. Care homes, however, need to go in the other direction. The current rules make no scientific sense and will harm many vulnerable people. That is why I and more than 60 experts and organisations have issued a call this week for action demanding that restrictions on care home visits in the UK be lifted. Almost 14,000 deaths in nursing and care homes in the UK were attributed to covid-19 between April and July 2020 and consequently residents in homes have had severe visiting restrictions imposed. Many have been almost completely isolated from usual family contact for months. In Scotland, for example, visiting a care home is allowed only if the entire home is free of any covid-19 symptoms for 28 days and even then there must be approval from the local director of public health. In Leeds, England, it isn’t illegal to visit, but local government guidance says you must have a very good reason, and the example given is if someone is dying. The problem is that most people in care homes are in the last two years of life. The median length of stay for people admitted to nursing beds is less than a year. Most people in care homes have dementia, and for them, the end-of-life phase can last for weeks, months or even years according to the Alzheimer’s Society, even though the rules about visiting often prevent family contact until the last few days. It is well documented that social isolation accelerates deterioration in people with dementia. So, these restrictions are killing people.
11-4-20 How the strangeness of our dreams reveals their true purpose
A new explanation for dreaming suggests it does something far more profound than reinforcing learning as we sleep. It might even explain our love of stories. IF ALIENS ever visited Earth, they might notice something strange. Nearly everyone, everywhere, spends a significant part of their day paying attention to things that aren’t real. Humans often care fiercely about events that never happened, whether in TV shows, video games, novels, movies. Why care so much about fictions? Perhaps, these aliens might hypothesise, humans are too stupid to distinguish between truth and falsehood. Or perhaps they pay attention to fake events for the same reason that they eat too much cheesecake: both are non-natural outcomes of evolved interests. The aliens’ confusion might deepen when they learned that humans fall asleep and dream. For dreams are also fictions. Dreaming takes time and energy, so presumably has an evolutionary purpose. The aliens might begin to wonder what they are missing about the importance of experiencing things that never happened. As someone who grew up in my family’s bookstore, and as a novelist, this question of the importance of fictions is especially dear to me. I think the imaginary aliens are in the same position as a scientist attempting to explain the evolved purpose of dreams – and if we can identify the biological reason for dreaming, we can ask if it applies to the artificial dreams we call fictions. As a neuroscientist, I’ve been working on a hypothesis that draws on what we’ve learned about artificial neural networks to cast dreaming as a way to improve our performance in waking life, just not in the way we might think. If correct, it may also explain some of this strange human attraction to the unreal in our waking lives.
11-4-20 Can antibodies from people with covid-19 bridge the gap to a vaccine?
FOR people who have survived covid-19, there is an opportunity to add another chapter to their recovery story: they could help save other people’s lives by donating blood. The plasma of people who have recovered from the disease contains precious antibodies that helped them fight off the virus, and could help others do the same, or even make them temporarily immune. Such antibodies are an increasing focus of research efforts to treat and prevent covid-19. According to senior US health official Anthony Fauci, antibody therapies could be a “bridge to a vaccine” – a stopgap to carry us safely to the promised land. The use of antibody-laden blood plasma was developed more than 100 years ago to treat diphtheria. It fell out of favour with the introduction of antibiotics, but was revived in 2002 during the SARS epidemic, and has since been used against Ebola and H1N1 flu. Another reason for plasma injection is to provide “passive” immunity, effectively a short-term vaccine for diseases such as hepatitis B. The research for using several types of plasma to treat covid-19 is still in its early stages. The most basic antibody therapy is convalescent plasma. The idea is simple: transfuse plasma from a recovered patient into a sick person’s bloodstream to give them an instant immune response. “It’s appealing because it’s a ready-made potential therapeutic,” says Jeffrey Sturek at the University of Virginia, who is running a convalescent plasma trial. “You can also borrow immunity from other people.” Plasma is the liquid part of blood, and donating it is similar to blood donation. Blood is siphoned from a vein in the arm, but then separated using a process called plasmapheresis. The plasma is retained but the red and white blood cells are infused back into the donor. Plasma infusions are similar to blood transfusions. The plasma is screened for pathogens, tissue-matched, then infused into the bloodstream.
11-4-20 Why South America’s ancient mammals may have lost out to northern counterparts
Extinctions left fewer animals available to migrate north, a study suggests. Millions of years ago, North American mammals flooded South America after the two continents joined. But South American mammals failed to return the favor, and now scientists have an idea why. A new analysis of fossils suggests that many native South American mammal groups were declining early in the continental coupling, leaving fewer species available to head north, researchers report October 5 in the Proceedings of the National Academy of Sciences. More than 10 million years ago, as the Pacific tectonic plate slid under the South American and Caribbean plates, the Isthmus of Panama began to rise out of the ocean, bridging North and South America. Animals began to move between the continents, in a trickle at first and then in a massive wave after the isthmus had fully formed around 3 million years ago. This exchange, known as the Great American Biotic Interchange, had a major influence on the distribution of mammals in the Americas today. South American mammals at the time of the event — having evolved for tens of millions of years on an island continent — were stupendously strange. Club-tailed armadillo relatives the size of small cars shuffled about (SN: 2/22/16). Vaguely camel-like and rhinolike herbivores grazed the landscape. Immense ground sloths shambled on land and even swam offshore. “This interchange was relatively balanced at first,” says Juan Carrillo, a paleobiologist at the National Museum of Natural History in Paris. But eventually, the switcheroo became asymmetric, with many more mammals with North American origins showing up in the south than vice versa. In fact, most of South America’s extraordinary creatures never managed to move north and persist into the modern era.
11-4-20 Squid-like creature that looked like a giant paperclip lived 200 years
An ancient squid-like animal with a shell that looked like a 1.5-metre-long paperclip may have typically lived for 200 years. Diplomoceras maximum lived about 68 million years ago, making it a contemporary of Tyrannosaurus rex. It was an ammonite – a now-extinct group of tentacled cephalopods – and it had a distinctive paperclip-shaped shell. “It’s hard not to be entranced,” says Linda Ivany at Syracuse University, New York. “It’s as tall as I am.” D. maximum’s unusual shell shape makes it difficult to unravel its biology, but Ivany and her colleague, Emily Artruc, have now uncovered hints that individuals might have had very long lives. The evidence comes from chemical signatures locked away in samples taken at regular intervals along a 50-centimetre-long section of D. maximum shell. When she and Artruc examined the carbon and oxygen isotopes along the shell, they found a repeating pattern in the isotopic signatures that they suspect reflects the annual release of methane from the sea floor. This annual pattern matched up with the sculptural ridges, or ribs, perpendicular to the length of the shell. This suggests that D. maximum added one new rib to its shell each year. “These shells grow by accretion, adding a new increment annually,” says Ivany. Given that a 1.5-metre-long shell contains many dozen ribs, that leads to an obvious conclusion. “The only scenario that seems to work is to make this thing 200 years old,” says Ivany, who presented the research at an online meeting of the Geological Society of America last week. At first glance, a 200-year-old shellfish might seem unremarkable, given that some modern shellfish can live more than twice as long. But D. maximum was a cephalopod, and all modern cephalopods live fast and die young. Octopuses and squid – even the gigantic forms – live no more than about 5 years. Nautilus, shelled cephalopods, can survive into their twenties. “These are not centenarians,” says Ivany.
11-4-20 A surprisingly tiny ancient sea monster lurked in shallow waters
A newfound species of nothosaur may have had a much different lifestyle from its larger kin. Around 240 million years ago, large reptiles called nothosaurs ruled the seas. These now-extinct sea monsters grew roughly five meters long or longer and flicked their long tails to speed through the water, chasing down fish. Now researchers have found fossils of a type of mini nothosaur with features that suggest the creature lived a very different lifestyle from its bigger cousins. Brevicaudosaurus jiyangshanensis may havelurked on the shallow seafloor, floating motionless until unsuspecting prey got too close, say researchers, who describe the new species October 28 in the Journal of Vertebrate Paleontology. Two B. jiyangshanensis fossils were found in quarries about a kilometer apart in South China. Their size — just about a half meter long, or about the size of a beagle — made the team initially think that it had stumbled upon baby nothosaurs, says Xiao-Chun Wu, a paleobiologist at the Canadian Museum of Nature in Ottawa. But the bones told a different story. “In the young [nothosaurs], the bones — especially in the limbs — are roundish,” Wu says. However, the bones in these fossils were developed into well-defined shapes, and the skull bones on the side of the head were fused, evidence that the creatures were adults. B. jiyangshanensis had various features not found on bigger nothosaurs. Its tail was short, broad and flat, and its bones were dense, all of which could have helped the reptilebalance its body as it floated in shallow water.“This is the first discovery of a small-sized species of a big-sized group,” Wu says. “This is a very new lifestyle we now know about nothosaurs.” The newly described reptile may have had large lungs relative to its body size, compared with other nothosaurs, helping it to stay underwater for longer. But future skeletal studies are needed to confirm that.
11-3-20 How COVID-19 may trigger dangerous blood clots
Clots may stem from immune cells that cast nets that trap red blood cells and platelets. Some of COVID-19’s dangerous blood clots may come from the immune system attacking a patient’s body rather than going after the virus, a new study suggests. It’s known that excessive inflammation from an overactive immune response can spur the clots’ formation in severely ill patients (SN: 6/23/20). Now researchers are teasing out how. Some of that clotting may come from auto-antibodies that, instead of recognizing a foreign invader, go after molecules that form cell membranes. That attack may prompt immune cells called neutrophils to release a web of genetic material geared at trapping virus particles outside of the cells. “Presumably in the tissues, this is a way to control infections,” says Jason Knight, a rheumatologist at the University of Michigan in Ann Arbor. “But if you do it in the bloodstream, it’s very triggering of thrombosis,” or clotting. That may be what happens in some COVID-19 patients, Knight, cardiologist Yogen Kanthi of the National Institutes of Health in Bethesda, Md., and their colleagues report November 2 in Science Translational Medicine. With COVID-19, blood clots in the lungs have been a significant cause of death, Kanthi says. And some blood clots may form when the webs trap red blood cells and platelets, creating a sticky clump that can clog blood vessels. “These are very intriguing findings,” says Jean Connors, a clinical hematologist at Harvard Medical School and Brigham and Women’s Hospital in Boston who was not involved in the work. “There has been a lot of speculation about what the presence of [the auto-antibodies] means and whether they have any pathogenic role.” Studies have revealed that some auto-antibodies can interfere with the immune response to viruses (SN: 9/25/20). Some preliminary work further suggests that auto-antibodies that bind to a variety of targets in the host may be a common feature in severely ill COVID-19 patients.
11-2-20 ‘Deaths of despair’ are rising. It’s time to define despair
Scientists investigate whether despair is distinct from mental disorders. As 2015 wound down, a foreboding but catchy phrase from a scientific paper blew across the cultural landscape with unexpected force. The expression “deaths of despair” was born after Princeton University economist Anne Case and Angus Deaton — Case’s colleague, husband and a Nobel laureate in economics — dug into U.S. death statistics and found that, during the 1900s, people’s life spans had generally lengthened from roughly 50 years to nearly 80. But then, near the end of the century, one segment of the population took a U-turn. Since the 1990s, mortality had risen sharply among middle-aged, non-Hispanic white people, especially those without a college degree, Case and Deaton reported in December 2015 in the Proceedings of the National Academy of Sciences. The reason, to a large extent: White, working-class people ages 45 to 54 were drinking themselves to death with alcohol, accidentally overdosing on opioids and other drugs, and killing themselves, often by shooting or hanging. Vanishing jobs, disintegrating families and other social stressors had unleashed a rising tide of fatal despair, Case and Deaton concluded. This disturbing trend mirrored what had previously occurred among inner-city Black people in the 1970s and 1980s, Case and Deaton now say. As low-skilled jobs vanished and families broke apart, Black victims of crack cocaine and the AIDS epidemic represented an early wave of deaths of despair. Even today, mortality rates for Black people still exceed those of white people in the United States for a variety of reasons, with Black overdose deaths on the rise over the last few years. “The most meaningful dividing line [for being at risk of deaths of despair] is whether or not you have a four-year college degree,” Deaton says.
11-2-20 Coronavirus: Are Indians more immune to Covid-19?
Millions of Indians have limited access to clean water, consume unhygienic food, breathe foul air and live in densely packed surroundings. Researchers have found this makes them susceptible to a host of non-communicable illnesses like heart and chronic respiratory diseases, cancer and diabetes. These contribute significantly to the disease burden, according to a government report. Air pollution alone kills more than a million Indians every year. The World Health Organisation says safe water, sanitation and hygienic conditions are essential for protection of health against Covid-19. A joint study by the WHO and the United Nations' children's agency, Unicef, found that nearly three billion people - some 40% of the global population and living almost entirely in developing nations - lack "basic hand washing facilities". This was enough to spark concerns that the coronavirus would tear through their populations, and lead to millions of deaths in countries such as India. "Typically access to healthcare facilities, hygiene and sanitation is poorer in these countries and is often believed to be the contributing factor of higher incidence of communicable diseases there. It was not unexpected that Covid-19 would have catastrophic consequences in the low and low-middle income countries," says Dr Shekhar Mande, director general of the Council of Scientific and Industrial Research (CSIR). India has a sixth of the world's population and a sixth of the reported cases. However, it accounts for only 10% of the world's deaths from the virus, and its case fatality rate or CFR, which measures deaths among Covid-19 patients, is less than 2%, which is among the lowest in the world. Now, new research by Indian scientists suggests that low hygiene, lack of clean drinking water, and unsanitary conditions may have actually saved many lives from severe Covid-19.
11-1-20 The new neuroscience of stuttering
Gerald Maguire has stuttered since childhood, but you might not guess it from talking to him. For the past 25 years, he has been treating his disorder with antipsychotic medications not officially approved for the condition. Only with careful attention might you discern his occasional stumble on multisyllabic words like "statistically" and "pharmaceutical." Maguire has plenty of company: More than 70 million people worldwide, including about 3 million Americans, stutter — they have difficulty with the starting and timing of speech, resulting in halting and repetition. That number includes approximately 5 percent of children (many of whom outgrow the condition) and 1 percent of adults. Their numbers include presidential candidate Joe Biden, deep-voiced actor James Earl Jones, and actress Emily Blunt. Though they and many others, including Maguire, have achieved career success, stuttering can contribute to social anxiety and draw ridicule or discrimination. Maguire, a psychiatrist at the University of California, Riverside, has been treating people who stutter, and researching potential treatments, for decades. He's now embarking on a clinical trial of a new medication, ecopipam, that streamlined speech and improved quality of life in a small pilot study in 2019. Others, meanwhile, are delving into the root causes of stuttering. In past decades, therapists mistakenly attributed stuttering to defects of the tongue and voice box, to anxiety, trauma, or even poor parenting — and some still do. Yet others have long suspected that neurological problems might underlie stuttering, says J. Scott Yaruss, a speech-language pathologist at Michigan State University. The first data to back up that hunch came in 1991, when researchers reported altered blood flow in the brains of people who stuttered. Since then research has made it more apparent that stuttering is all in the brain. "We are in the middle of an absolute explosion of knowledge being developed about stuttering," Yaruss says. There's still a lot to figure out, though. Neuroscientists have observed subtle differences in the brains of people who stutter but can't be certain if those differences are the cause or a result of the stutter. Geneticists are identifying variations in certain genes that predispose a person to stutter, but only recently have their links to brain anatomy become apparent. Maguire, meanwhile, is pursuing treatments based on dopamine, a chemical messenger in the brain that helps to regulate emotions and movement (precise muscle movements, of course, are needed for intelligible speech). Only when experts look closely at the brain's structure and activity do subtle differences between groups who do and don't stutter become apparent. It's all about connections between different brain parts, says speech-language pathologist and neuroscientist Soo-Eun Chang of the University of Michigan. For example, in the brain's left hemisphere, people who stutter often appear to have slightly weaker connections between the areas responsible for hearing and for the movements that generate speech. Chang has also observed structural differences in the corpus callosum, the big bundle of nerve fibers that links the brain's left and right hemispheres. These findings hint that stuttering might result from slight delays in communication between parts of the brain. Chang has been trying to understand why about 80 percent of kids who stutter grow up to have normal speech patterns, while others continue to stutter. Stuttering typically begins around age 2. Chang studies children for up to four years, starting as early as possible, looking for changing patterns in brain scans. In kids who lose their stutter, Chang's team has observed that the connections between areas involved in hearing and ones involved in speech movements get stronger over time. But that doesn't happen in children who continue to stutter.