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2019 Scientists Stats

96 Evolution News Articles
for December 2019
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Nature cares only that you reproduce and raise the kids.
After you've done that, get out of the way.


12-30-19 Misunderstanding the vulva may be leading to pain after labiaplasties
Cosmetic genital surgery is increasingly popular, but new research suggests crucial nerves are at greater risk of injury during vulval surgery than many surgeons may realise. Textbooks rarely depict or describe the dorsal nerves going to the clitoris, and the organ is often depicted as smaller than it is, says Paul Pin at the Baylor University Medical Center in Dallas, Texas. Basic anatomical research on the clitoris has lagged behind that of the penis, he says. To address this, he and his colleagues dissected the clitoral regions of 10 cadavers of women aged 43 to 88. They found that the nerves responsible for sensation and orgasm ranged from 2 to 3 millimetres in diameter, similar in size to the nerves running along the shaft of the penis and in the index finger. These nerves sit millimetres under the surface of the clitoral hood, the fold of skin that protects the pea-sized glans. Similar measurements were found in a study of 27 cadavers led by Marlene Corton at the University of Texas Southwestern Medical Center. These studies are the first to thoroughly measure the size of the clitoral dorsal nerves, and they change the conventional understanding that these nerves are small and situated deep below the surface. Labiaplasties are cosmetic surgeries designed to reduce the size of the fleshy lips of the vulva, though surgeons sometimes also reduce the size of the clitoral hood. Pin worries that a lack of information on clitoral anatomy means many surgeons performing labiaplasties don’t realise the nerves are even there. “But they are large, superficial and therefore very susceptible to injury if you don’t know what you’re doing,” he says. This is concerning in light of the growing popularity of labiaplasties. Between 2003 and 2013, Australia saw a threefold rise in the procedure, and the UK experienced a fivefold increase. In the US, there was a nearly 500 per cent increase in the surgery between 2011 and 2018.

12-30-19 A bioethicist says scientists owe clinical trial volunteers support
Many insurance policies don’t cover experimental procedures or side effects that can follow. Some people see clinical trials as a chance for a miracle cure. In reality, these experimental drug tests and medical interventions often fail. With researchers in the United States now testing the gene editor CRISPR/Cas9 for the first time in people with cancer, blood disorders or inherited blindness (SN: 8/14/19), one bioethicist says it’s important to remind scientists running these trials and others about the responsibilities researchers bear for study volunteers. That’s not to say that scientists doing clinical trials are doing anything wrong or that such studies should stop, says Laurie Zoloth of the University of Chicago. Her role as a bioethicist, she explains, is “to make sure that human progress goes forward in a way that’s safe and ethical.” Clinical trials in people — whether testing new drugs, devices, surgical methods or CRISPR technology — must meet higher ethical standards than work conducted in a lab, she says. “Having a human being as a subject means you have different obligations than you would to an animal or a petri dish,” Zoloth says. A scientist conducting clinical trials on humans should be “responsible for them, in my opinion, forever.” That means that researchers should pay not just for the experimental treatment, she says, but also for any treatment needed for treating side effects — including those that show up later — or if something goes wrong during the trial. Many people’s insurance policies do not cover experimental procedures, yet some informed consent forms required for participating in clinical trials contain clauses claiming that a subject’s insurance will cover side effects, she notes. When Zoloth and others who review research applications point this out to scientists, “sometimes they’re surprised that they haven’t thought of it,” she says. But “sometimes they hope that, by putting that [clause] in there, it will release them from some burden.”

12-30-19 Scientist behind world’s first gene-edited babies sentenced to prison
The scientist behind the birth of the world’s first gene-edited babies has been sentenced to three years in prison. He Jiankui, who announced he had used CRISPR technology on embryos that led to two births in 2018, has also been fined 3 million yuan, equivalent to about $430,000, according to Chinese state news agency Xinhua. On Monday 30 December, a court in Shenzen found that He and his colleagues forged ethical review materials, violated national regulations on scientific research and medical management and caused harm to society, according to the report. Two of He’s colleagues, Zhang Renli and Qin Jinzhou, have also been given prison sentences and fines. All three pleaded guilty in a private trial. They also face a lifelong ban on engaging in any human assisted reproductive technology services and some scientific research projects. Robin Lovell-Badge at the Francis Crick Institute in London told the UK Science Media Centre that a prison sentence and fine would also have been the likely penalties if someone had conducted similar work in the UK. The birth of two gene-edited twin girls was announced by He at a conference in 2018, days after news reports revealed the first details of his experiments. He claimed to have used CRISPR gene editing technology to disable a gene for a protein that the HIV virus binds to. His team hoped that the babies would be born resistant to HIV. The team created 22 embryos using cells from seven couples, and 16 appeared to have been successfully gene edited. Eleven were implanted into women, with one woman becoming pregnant. There were other issues with the experiment. All of the fathers in the study were HIV positive, but this doesn’t mean that they would have passed the infection to their children – HIV transmission can be controlled with simple medical measures, with no need for experimental genetic techniques. And there are concerns that CRISPR can have unpredictable effects on other genes.

12-30-19 China jails 'gene-edited babies' scientist for three years
A scientist in China who said he had created the world's first gene-edited babies has been jailed for three years. He Jiankui was convicted of violating a government ban by carrying out his own experiments on human embryos, to try to give them protection against HIV. He was globally condemned when he announced his experiments, and the birth of twin babies, last November. Xinhua news agency said a third baby was also born at the same time, which had not previously been confirmed. The local government in Guangdong province said it was keeping the babies under medical observation. As well as the prison sentence, He was fined three million yuan ($430,000; £328,000). The court also handed lower sentences to two men, Zhang Renli and Qin Jinzhou, for conspiring with He to carry out the experiments. A court in Shenzhen said the men had acted "in the pursuit of personal fame and gain", and had seriously "disrupted medical order", Xinhua news agency reported. "They've crossed the bottom line of ethics in scientific research and medical ethics," the court added. He announced the birth of gene-edited twins called Lula and Nana in a video, filmed by Associated Press, in November 2018. Describing his experiments, He said: "I understand my work will be controversial - but I believe families need this technology and I'm willing to take the criticism for them." After the video was released, the backlash from the science community both in China and around the world was swift and forceful. The Chinese government placed He under police investigation and ordered his research work be stopped. He was also fired by the university where he was an associate professor, the Southern University of Science and Technology in Shenzhen. The Chinese Academy of Science released a statement about He, saying it "firmly opposed" gene editing on humans.

12-29-19 Some types of endometriosis may be present from birth
One in 10 women live with endometriosis, but we still don’t know its exact cause. New evidence suggests that some cases may be present from birth, and that different subtypes of the condition may benefit from different treatments. Endometriosis is diagnosed when endometrial cells from the lining of the uterus are found elsewhere in the body. When people with the condition menstruate, these patches of cells, wherever they are, bleed. This is thought to be at least partly responsible for the debilitating pain people with endometriosis often experience, although we still don’t really know. Those affected often find it harder to conceive, too. One of the more established ideas to explain what causes endometriosis suggests that these rogue cells are the product of “retrograde menstruation”. The idea is that some menstrual blood ends up being returned into the body, taking these uterine cells with it and enabling them to implant in the wrong place. But this idea doesn’t explain all cases of endometriosis, says Katie Leap at the University of California, Los Angeles. “You can find endometriosis in fetuses, in men and in girls who haven’t menstruated,” she says. To learn more about the problematic patches of cells, known as lesions, Leap and her colleagues compared them with typical cells found in the uterus lining. Specifically, they looked at the cells’ epigenetic age: their biological age based on the presence or absence of chemicals that switch genes on or off. The researchers analysed tissue samples collected from 60 women, 35 of whom had endometriosis. They found that the biological ages of the tissues were different. While uterus cells had an age similar to the women’s chronological age, the cells from endometriosis lesions were around 16 years younger on average (bioRxiv, doi.org/dg99).

12-29-19 Four great waves of animals have spread out from the tropics
The tropics are the most biodiverse regions on Earth. Now there is evidence that they are also the main source of evolutionary innovation and diversity. Complex animals have dominated Earth for 541 million years, a time span called the Phanerozoic eon. Huge numbers of species have evolved and gone extinct during this time, in a complex story that includes fish, giant reptiles and whales. However, in the 1980s palaeontologist John Sepkoski analysed the overall pattern of evolution in the sea, where the fossil record is best. He concluded that marine evolutionary history could be broken down into three supergroups, which he called “great evolutionary faunas”. The first group was dominated by trilobites, which resembled woodlice, and bristle worms; the second by shellfish-like creatures called brachiopods; and the third by molluscs, which have persisted to the present day. Other animals like land mammals probably followed similar patterns, but their fossil record isn’t complete enough for us to know. Now, by analysing nearly 18,300 marine genera from the Phanerozoic fossil record, Alexis Rojas-Briceno of Umeå University in Sweden and his colleagues have found that the evolution of complex marine life is best described using four great groups of fauna, not three (bioRxiv, doi.org/dg98). The first supergroup existed between 541 and 494 million years ago, spanning the Cambrian explosion in which many animal groups first emerged. As in the original analysis, trilobites dominated. The second supergroup, dubbed the Palaeozoic, lasted from 494 to 252 million years ago. Creatures with hard outer shells were now widespread, including brachiopods. This phase ended when the end-Permian extinction wiped out almost all complex life on Earth.

12-28-19 Wearing shoes from a young age makes your ankles less flexible
Your shoes are changing your feet. The ankles of people who habitually wear shoes are different to those of people who walk barefoot. These changes to ankle bones take place over the course of a person’s life, and there is no evidence that they can be passed on genetically. In modern industrial societies, most people wear shoes from a young age. However, in traditional hunter-gatherer societies people often go barefoot, or wear only very thin footwear. “We know that there are some variations in the feet of modern humans, due to the use of shoes,” says Rita Sorrentino of the University of Bologna in Italy. But most previous findings relate to the front and middle of the foot. Sorrentino and her team have focused on the ankle, which is crucial because it links the foot to the leg. They studied 142 ankle bones from 11 populations from North America, Africa and Europe. These included modern sandal-wearing Nguni farmers in southern Africa, people living in modern New York, and preserved bones from Stone Age hunter-gatherers. The hunter-gatherers’ ankle bones were significantly shorter than those of people living in modern cities, and there were other differences in the shape. “They are mostly related to footwear-related behaviours and locomotor behaviours,” says Sorrentino. The hunter-gatherers walked barefoot for long distances every day over natural terrain. Their ankles were relatively flexible. In contrast, the people who live in big cities wear constrictive footwear and walk short distances on flat surfaces like asphalt roads. Their ankles were more rigid. “There is a loss of flexibility,” says Sorrentino.

12-29-19 The best health advice from 2019
From napping to tattoos, here's what the experts had to say. Napping may boost your heart health. That's the finding of researchers in Switzer­land, who tracked 3,462 healthy adults for five years. Those who dozed for five minutes to an hour once or twice a week were 48 percent less likely to suffer a heart attack, stroke, or heart failure than those who never snoozed in the daytime. Napping longer or more often didn't deliver any additional health benefits. Lead author Nadine Häusler says it's still unclear how napping might influence heart health. "Our best guess," she says, "is that a daytime nap just releases stress from insufficient sleep." Eating mushrooms could lower your chances of developing memory problems in later life. A study involving 663 Chinese men and women found that those who ate one or two 5-ounce portions of mushrooms a week had a 43 percent lower risk of developing mild cognitive impairment — a precursor to Alzheimer's — than participants who consumed less than one. Those who ate more than two portions had a 52 per­cent reduced risk. Lead author Lei Feng says the most likely explanation for this "dramatic effect" is that the fungi contain antioxidants that protect neurons from damage. Having kids makes you happier — once they've grown up and moved out. Previous research has shown that, earlier in life, people with children are less happy and more prone to depression than childless peers, partly because they get less sleep and experience more stress. But a study of 55,000 Europeans found that parents were more likely to be happier when they got older, provided their offspring had flown the nest. Researchers say grown kids can offer parents more social and emotional connection, as well as care and other support. "There is no simple answer on whether children bring happiness," says lead author Christoph Becker. "It depends on which stage of life your children are at." (Webmaster's comment: And many more; Running, NSAIDs, Northern Irish soil, and High-fiber foods.)

12-23-19 Lewis stone circle has star-shaped lightning strike
Evidence of a "massive" lightning strike has been found at the centre of a stone circle in the Western Isles. A single large strike, or many smaller ones on the same spot, left a star-shaped magnetic anomaly at the 4,000-year-old site in Lewis. Scientists made the discovery at Site XI or Airigh na Beinne Bige, a hillside stone circle now consisting of a single standing stone. The site is at the famous Calanais Standing Stones. Scientists said the lightning strike, which was indentified in a geophysics survey, could show a potential link between the construction of ancient stone circles and the forces of nature. They said the lightning struck some time before peat enveloped the stone circle at Site XI 3,000 years ago. The discovery is detailed in new research published online. Dr Richard Bates, of the University of St Andrews, said: "Such clear evidence for lightning strikes is extremely rare in the UK and the association with this stone circle is unlikely to be coincidental. "Whether the lightning at Site XI focused on a tree or rock which is no longer there, or the monument itself attracted strikes, is uncertain. "However, this remarkable evidence suggests that the forces of nature could have been intimately linked with everyday life and beliefs of the early farming communities on the island." The discovery was made by the Calanais Virtual Reconstruction Project, a joint venture led by the University of St Andrews with standing stones trust Urras nan Tursachan and the University of Bradford and supported by funding from Highlands and Islands Enterprise. The same project has also produced a 3D virtual model recreating another of the area's "lost" stone circle, Na Dromannan. Its stones are today either lying flat or buried under peat.

12-23-19 Cell injection could train the body not to reject organ transplants
A one-off injection of cells could be a long-sought solution to the problem of the body rejecting an organ transplant. The first person who may have benefited from this approach is an Italian man who had a kidney transplant. He has been completely tolerating his new organ for 19 months without anti-rejection medicines. Transplants can be life-saving, but to stop the donor organ being rejected by the recipient’s immune system, people have to take several drugs that have serious side effects, including cancer and infections – and they don’t always work. The new treatment involves injecting mesenchymal stromal cells. This can be done the day before the transplant and seems to damp down the recipient’s immune reaction in a way that “teaches” the body to accept the different tissues. This type of cell can come from a variety of sources. Giuseppe Remuzzi at the Mario Negri Institute for Pharmacological Research in Milan and his team took them from the recipient’s bone marrow, multiplied them in the lab, and reinjected them. After two years, blood tests suggested he was tolerating his new kidney so his anti-rejection medicines were gradually reduced over about five years and then stopped. But it isn’t clear if the cells were definitely responsible; in a second person given the treatment, blood tests didn’t show tolerance. A few previous kidney recipients have developed tolerance to their new organ spontaneously – so perhaps the Italian man’s response was another of these rare cases, says Emily Thompson at Newcastle University in the UK, who wasn’t involved in the work. If the cells really were responsible, she says “it would be a pretty big deal”. Although the success of the treatment in the first case is unproven, studies by other groups suggest these kinds of cells can promote at least some level of tolerance. When six Dutch kidney transplant recipients showing initial signs of rejection were injected with the cells twice as an emergency treatment, they later showed signs of improved donor organ tolerance in blood tests.

12-22-19 Potatoes engineered to harm a major pest but leave other insects safe
An ideal pesticide would kill only pests, leaving all other creatures unharmed. Now biologists have engineered potatoes to be lethal to a major pest called the Colorado potato beetle but harmless to other species, no pesticide required. Ralph Bock of the Max Planck Institute of Molecular Plant Physiology in Germany has genetically modified potatoes to produce RNA molecules that, when eaten, shut down an important gene in the beetle. The approach is based on a technique known as gene silencing or RNA interference. “Currently there’s a lot of excitement about it,” says Bock. “I’m quite optimistic that it will provide an additional weapon to deal with pest insects.” The genes in DNA act by making proteins, but to do this, their instructions are first copied into single-strand RNA molecules. But if double-stranded RNA molecules are present in a cell, it is usually a sign of viral infection, and triggers the cell to destroy any RNA sequences matching this particular string of genetic code. This defense system is easily tricked. To silence the activity of a particular gene in an organism’s cells so that it stops making proteins, all you need to do is introduce some double-stranded RNA that contains that gene’s code. he difficult bit is getting RNAs into cells. In most animals, including us, any RNAs in the gut or bloodstream are quickly destroyed. In the 2000s, researchers discovered that some insects absorb double-stranded RNAs from their guts. Simply feeding them such RNAs is enough to trigger gene silencing in much of their bodies. Trials by several groups since have shown that spraying RNAs onto crops can protect them from pests while leaving some closely related insects unharmed. But producing the vast quantities of RNAs needed to do this would be extremely expensive, says Bock. One solution is to genetically modify plants to produce pest-targeting RNAs themselves, rather than spraying these onto them. A maize variety called SmartStax Pro that produces RNAs that target the western corn rootworm pest has been approved in several countries, but is yet to go on sale.

12-21-19 In a first, an Ebola vaccine wins approval from the FDA
The drug is crucial to efforts to curb an ongoing outbreak of the deadly disease in Congo. An Ebola vaccine, already deployed against the often deadly disease in an ongoing outbreak in Congo, is the first approved by the U.S. Food and Drug Administration. The vaccine, called Ervebo and developed by the pharmaceutical company Merck, underwent testing during the 2014–2016 Ebola outbreak in West Africa and was found to be effective at warding off an infection (SN: 12/22/16). Approved for those 18 and older, the vaccine prevents disease caused by one species of Ebola virus, Zaire ebolavirus. The FDA’s action, announced December 19, follows in the footsteps of European regulators’ approval in November (SN: 12/16/19). While cases of Ebola in the United States are extremely rare, the FDA considers the vaccine a crucial tool to stop the spread of the disease. In Congo’s Ebola outbreak, there have been 3,351 cases and 2,211 deaths as of December 18, according to the World Health Organization (SN: 5/21/18). More than 250,000 people have been vaccinated. Health officials working to control the outbreak have been aided by the vaccine as well as experimental treatments for those already infected (SN: 2/11/19). Two of the four treatments proved effective at preventing death from the disease in a clinical trial conducted during the outbreak (SN: 8/12/19). (One of those treatments is made by Regeneron Pharmaceuticals, a major financial supporter of the Society for Science & the Public, which publishes Science News.) The number of new cases has been declining, but conditions in the country remain treacherous for those working to bring the outbreak to an end. In late November, armed attackers killed four workers assisting in the outbreak, including a member of a vaccination team.

12-20-19 Airplane sewage may be helping antibiotic-resistant microbes spread
Around 90 percent of sampled globetrotting E. coli were resistant to at least one drug. Sewage from airplanes serves as a melting pot for a globally sourced group of gut microbes. Now, a study suggests that such waste is loaded with bacteria resistant to antibiotics along with a smorgasbord of genes that confer drug resistance. That means airplane waste could be helping to fuel the spread of antibiotic resistance around the world. In a survey of airplane sewage from five German airports, around 90 percent of 187 E. coli isolated and tested were resistant to at least one antibiotic. For comparison, between 45 and 60 percent of these common gut dwellers collected from inlets to German wastewater treatment plants were drug resistant, the scientists found. And E. coli from airplane sewage was far more likely than that from municipal wastewater to be resistant to three or more antibiotics, researchers report in the Dec. 3 Environmental Science & Technology. “This is really important work,” says Amy Pruden, an environmental engineer at Virginia Tech in Blacksburg who was not involved with the study. “You read it, and you think, ‘somebody should have done this sooner.’” When microbes are resistant to multiple drugs, it can make infections difficult to treat or even deadly (SN: 8/16/19). A recent government report estimates that infections of drug-resistant fungi and bacteria claim about 35,000 lives in the United States every year (SN: 11/13/19). Scientists and public health officials have tended to focus on hospitals as places where these “superbugs” can arise. But people may want to pay special attention to how airport sewage is contained and treated, Pruden says. In this study, airplane sewage E. coli far surpassed drug resistance reported for microbes sampled in German hospitals. The airplane sewage had eight times the prevalence of E. coli resistant to three specific drug classes used to treat urinary tract infections caused by this microbe.

12-20-19 Blood test for Alzheimer’s
Doctors could soon use a simple blood test to predict if a patient will develop Alzheimer’s, years before symptoms appear. An international team of researchers found that people genetically predisposed to the disorder had distinctly higher levels of neurofilament light chain—a protein found in the brain and spinal cord—seven years before symptoms began, and noticeably faster-growing levels more than 16 years in advance. An early test could help scientists determine whether new Alzheimer’s drugs are effective. Study author Mathias Jucker says the reason there is no effective treatment for the condition is “partly because current therapies start much too late.”

12-20-19 The new CRISPR
Scientists have developed a gene-editing tool that could one day correct 89 percent of the genetic mutations that cause inherited diseases, such as cystic fibrosis and sickle cell anemia. The most popular existing gene-editing approach, CRISPR-Cas9, uses “molecular scissors” to locate faulty genetic code, then cuts both strands of the DNA double helix and splices in a new section of code. Though cheap and fast, this process often damages nearby code or inserts the new material in the wrong place. The new technology, known as prime editing, cuts only one strand of the double helix—minimizing the risk of unintended changes.

12-20-19 Vaping
Vaping may damage blood vessels. Using MRI scans, University of Pennsylvania scientists monitored blood flow in 31 nonsmokers. After participants had several puffs on an e-cigarette without a flavor or nicotine, their blood flow was noticeably worse. Overall, vaping temporarily constricted arteries in the legs, heart, and brain by more than 30 percent. The researchers believe glycerol and propylene glycol, the core ingredients of vape fluid besides water, can irritate the lining of blood vessels. More than 2,400 people have been hospitalized over the past year for vaping-related lung illnesses, and at least 52 have died. Scientists suspect many had vaped illicit liquids containing THC—the psychoactive compound in marijuana—that had been cut with vitamin E acetate, a sticky oil that can cling to the lungs.

12-20-19 Having kids
Having kids makes you happier—once they’ve grown up and moved out. Previous research has shown that, earlier in life, people with children are less happy and more prone to depression than childless peers, partly because they get less sleep and experience more stress. But a study of 55,000 Europeans found that parents were more likely to be happier when they got older, provided their offspring had flown the nest. Researchers say grown kids can offer parents more social and emotional connection, as well as care and other support. “There is no simple answer on whether children bring happiness,” says lead author Christoph Becker. “It depends on which stage of life your children are at.”

12-20-19 Mushrooms
Mushrooms could lower your chances of developing memory problems in later life. A study involving 663 Chinese men and women found that those who ate one or two 5-ounce portions of mushrooms a week had a 43 percent lower risk of developing mild cognitive impairment—a precursor to Alzheimer’s—than participants who consumed less than one. Those who ate more than two portions had a 52 percent reduced risk. Lead author Lei Feng says the most likely explanation for this “dramatic effect” is that the fungi contain antioxidants that protect neurons from damage.

12-20-19 High-fiber foods
High-fiber foods can shrink your risk of dying early or developing a chronic condition. A scientific review commissioned by the World Health Organization noted that people who ate the most fiber—found in fruit, vegetables, and whole-grain cereals, pasta, and bread—were 15 to 30 percent less likely to die prematurely than those who ate the least. Heavy fiber consumers were also 16 to 24 percent less likely to suffer a stroke or develop heart disease, type 2 diabetes, or colorectal cancer. The optimal fiber intake was 25 to 29 grams a day; American adults consume an average of 15 grams.

12-20-19 White meat
White meat may raise your cholesterol levels as much as red meat. Researchers put 113 adults on three rotating monthlong diets: one centered on lean cuts of beef, the second on lean cuts of chicken, and the third on plant proteins. Half the participants’ diets—irrespective of their main protein source—were high in saturated fats, while half were low. Overall, white meat raised levels of LDL cholesterol, the so-called bad cholesterol that clogs arteries, just as much as red meat—even when saturated fat levels were equal.

12-20-19 Ultraprocessed foods
Ultraprocessed foods can shorten your life. A French study found that every 10 percent increase in consumption of these foods—such as chicken nuggets, potato chips, and ready-to-eat meals—was linked to a 14 percent higher risk of early death. The researchers say some additives in ultraprocessed products are carcinogenic and that chemicals from packaging may leak into the foods. Co-author Mathilde Touvier recommends people “avoid these foods as much as they can.”

12-20-19 In some languages, love and pity get rolled into the same word
A study of over 2,000 languages shows how words used to describe feelings vary across cultures. Lexically speaking, love is love. Except when it’s not. In some languages, the word for love comes tinged with pity. By analyzing the meanings of words used to describe emotions in over 2,000 languages, researchers found some universal truths. But the analysis, described in the Dec. 20 Science, also revealed cultural quirks. That includes “hanisi,” which, in the Rotuman language spoken just north of Fiji, refers to both love and pity. Figuring out how people label their emotions with words may give clues about how different cultures experience the world (SN: 9/10/19). Along with colleagues, psychologists Joshua Conrad Jackson and Kristen Lindquist of the University of North Carolina at Chapel Hill studied emotion words from 2,474 languages spanning 20 major language families. The researchers looked for words that were used to describe similar concepts (“water” and “sea,” for instance, but not “water” and “sun”). Among emotion words, an overall structure emerged. Generally, words used to communicate good and bad feelings were distinct from each other, and so were words for feelings that rev up the body. “People around the world may all feel bad when they lose a loved one, and people around the world may feel their heart begin to beat faster in the face of danger,” Jackson says. But against this backdrop, researchers found differences. In some Indo-European languages, for instance, “anxiety” and “anger” overlap. But “anxiety” is more closely tied to “grief” and “regret” among Austroasiatic languages, the large language family of mainland Southeast Asia. “Surprised” goes with “fear” in some languages, but not in others, the researchers found.

12-19-19 Fossil trees reveal world's oldest forest grew on New York mountains
The remnants of the oldest known forest have been identified in a New York quarry. The fossils are 386 million years old, and studying them could teach us more about how Earth’s climate has changed over time. “Charles was just walking across the floor of the quarry and he noticed these big root structures which are very distinctive” says Christopher Berry at Cardiff University in the UK, referring to Charles Ver Straeten at the New York State Museum. Ver Straeten discovered the fossils in 2008 near Cairo in the Catskills region of New York. Three types of trees were found in the forest. One of them, a member of the Archaeopteris genus, which is characterised by long roots, had roots stretching up to 12 metres. These trees are similar to modern coniferous trees and were the first known to have evolved flat green leaves. New York is well stocked with old tree fossils because the state lies on an ancient mountain range, which buried these trees by shedding sediment through natural erosion by rainfall and glaciation. The latest fossil find was just 40 kilometres away from what was previously considered the oldest forest in the world, beating the record by at least two million years. These trees played an important role in the development of life on Earth, helping to cool the planet. “All these trees appearing was having an effect of removing carbon dioxide from the atmosphere,” says Berry. “By the end of the Devonian period [360 million years ago], the amount of carbon dioxide was coming down to what we know it is today.” Studying the fossils could help us with modern climate change, says Sandy Hetherington at University of Oxford. “Understanding how this happened in the past is crucial for predicting what will happen in the future in light of climate change and deforestation,” she says.

12-19-19 World's oldest fossil trees uncovered in New York
The earliest fossilised trees, dating back 386 million years, have been found at an abandoned quarry in New York. Scientists believe the forest they belonged to was so vast it originally stretched beyond Pennsylvania. This discovery in Cairo, New York, is thought to be two or three million years older than what was previously the world's oldest forest at Gilboa, also in New York State. The findings throw new light on the evolution of trees. It was more than 10 years ago that experts from Cardiff University, UK, Binghamton University in the US and the New York State Museum began looking at the site in the foothills of the Catskill Mountains in the Hudson Valley. Since then, they have mapped over 3,000 square metres of the forest and concluded the forest was home to at least two types of trees: Cladoxylopsids and Archaeopteris. A third type of tree has yet to be identified. Palaeobotanist Dr Chris Berry from Cardiff University is a co-author of the study in the journal Current Biology. "This is the oldest place where you can wander around and map out where fossil trees were standing back in the middle part of the Devonian era." Researchers say they also discovered very long, woody roots that transformed the way plants and soils gather water. "It's a very ancient forest from the beginnings of the time where the planet was turning green and forests were becoming a normal part of the Earth's system," said Dr Berry. It's understood the forest was wiped out by a flood. The researchers have found fish fossils on the surface of the quarry. The point in time that the fossil trees date to marks a transition between a planet with no forests and a planet that is largely covered in trees. Dr Berry says studying the site can give us a better understanding of how trees evolved and how they draw down carbon dioxide (CO2) from the atmosphere.

12-19-19 Could CRISPR babies experiment have been made public earlier?
A year ago, the world was reeling from the news that a woman in China had given birth to two genetically edited girls. Many questions remain over the episode, including details of the experiment on the “CRISPR babies”, what happened to a second pregnancy and the fate and whereabouts of the Chinese researcher behind the trial, He Jiankui. But recent revelations that He’s paper was sent to two major scientific journals also raise questions for scientific publishers, the traditional gatekeepers of science who are increasingly pressured to be ethical police too. Nature had the paper in November 2018, before the experiment became public at the end of the month, and it was also submitted to JAMA, it was reported earlier this month. Nature told New Scientist it neither confirmed nor denied it had received the paper. JAMA didn’t respond. The precise timelines are fuzzy, but it is unlikely that any journal could have prevented He from proceeding with a second pregnancy. Researchers with knowledge of the pregnancy said in July that it was around full-term, suggesting that the fetus was conceived before editors ever saw the paper. But should the journals have taken greater action to alert authorities over potential ethical issues in He’s manuscript? The paper seemed to have ethical approval, but an investigation by Chinese authorities later concluded that the approval certificate was “fake”. The journal editors couldn’t have known or discovered that. “One of the things a journal does have a challenge with is, you’re not in a position to verify [ethics] approval,” says Richard Sever at Cold Spring Harbor Laboratory Press in New York. Kiran Musunuru at the University of Pennsylvania says he thinks Nature could have contacted He’s university in Shenzhen about the ethical issues. We don’t know if that happened. A spokesperson for Nature says its policy is to alert “relevant institutions” of potential ethical issues. Both journals are members of the Committee on Publication Ethics, whose guidance tells journals to raise ethical concerns with authors and, later, their employers. (Webmaster's comment: Not done first by the United States therefore it has to be wrong to do!)

12-19-19 Homo erectus’ last known appearance dates to roughly 117,000 years ago
New evidence helps resolve a debate over how long ago the hominid survived in what’s now Indonesia. Homo erectus, a humanlike species that dispersed from Africa into parts of Europe and Asia roughly 2 million years ago, eventually reached the Indonesian island of Java before dying out. Scientists say they have now resolved a controversy over just how long ago the last known H. erectus inhabited the Southeast Asian island. New evidence narrows the timing of this hominid’s final stand on Java to between 117,000 and 108,000 years ago, says a team led by geochronologists Yan Rizal of Indonesia’s Bandung Institute of Technology and Kira Westaway of Macquarie University in Sydney. The scientists present their results December 18 in Nature. If the findings hold up to scrutiny, the fossils would be the last known occurrence of H. erectus anywhere in the world, and would show that the hominid was part of a complex interplay among different Homo species in Southeast Asia that started more than 100,000 years ago. Excavations at Java’s Ngandong site from 1931 to 1933 uncovered 12 skullcaps and two lower leg bones from H. erectus. Since then, uncertainty about how Ngandong sediment layers formed and confusion about the original location of the excavated fossils has led to dramatically contrasting age estimates for the finds. A 1996 report in Science dated the Ngandong specimens to between 53,000 and 27,000 years ago, suggesting that H. erectus had lived alongside Homo sapiens in Indonesia (SN: 12/14/96). But a more recent analysis greatly increased the estimated age of the Java fossils, dating them to around 550,000 years ago (SN: 4/16/10). In the new study, researchers uncovered the spot where H. erectus fossils had been found, and then excavated and dated nonhuman animal fossils from the site, including large, hoofed creatures related to water buffalo. Those estimates relied on measures of radioactive uranium decay in bones and of tooth enamel damage from natural radioactivity in the soil and from cosmic rays, energetic particles from space that continually bombard Earth.

12-18-19 2019 saw the tragic and unnecessary return of measles in the US
Once deemed a problem of the past in rich nations, the deadly infection has made a huge comeback, reports Chelsea Whyte. THE shocking resurgence of a deadly but preventable childhood infection this year has led to frustration and shame, and sparked debate about the role of public health systems and the limits of personal liberty. Figures from November revealed that there were 1261 confirmed measles cases in the US this year – up 239 per cent on 2018. This is the highest number of cases since 1992. Most occurred in people who hadn’t been vaccinated against measles, and 123 people were hospitalised. The largest outbreak, in New York City, was curbed just in time. “If it had gone on just one month longer, we would have lost our elimination status as a country,” says Lauren Gardner at Johns Hopkins University in Maryland. The UK did lose its World Health Organization elimination status in August. Measles has been bouncing back in Europe since the region’s record low in cases in 2016. But its return in the US has been more sudden. The disease initially took hold in New York state in ultra-Orthodox Jewish communities where resistance to vaccination was high and misinformation campaigns that included an anti-vaccination pamphlet deterred parents from following medical guidelines. To stop the disease spreading, Rockland county, New York, banned unvaccinated children from entering public areas such as schools and public transit, while people in New York City were required to provide proof of vaccination as part of investigations to trace the spread of the disease, or face a fine of $1000. Although the science of the benefits of vaccines is clear, there is debate about how best to improve take-up and counter misinformation. A recent study found that California’s 2015 ban on non-medical exemptions for vaccines based on religious or philosophical beliefs had only a very small effect on vaccination rates. (Webmaster's comment: What would you expect of a nation filled with the religious ignorance.)

12-18-19 Homo erectus lived recently enough that it may have met Denisovans
An early human species may have survived in Java, Indonesia, until 108,000 years ago. Homo erectus endured so long that individuals may have interbred with more recent hominins, like the mysterious Denisovans. It has long been unclear when H. erectus died out. Now a reanalysis of the youngest known remains may have pinned down the extinction date. H. erectus was one of the first species in our genus, Homo. It evolved in Africa about 2 million years ago, then spread across Europe and Asia. Compared with earlier species, H. erectus had relatively large brains and used tools skilfully – although it was surpassed in both respects by later groups like Neanderthals and modern humans. H. erectus may be our direct ancestor. H. erectus died out before modern humans reached Java, so it is unlikely the two species crossed paths. That means our species isn’t in the frame for its extinction. The last known H. erectus lived near the Solo River in Ngandong, Java. The remains were discovered in the 1930s but scientists have struggled ever since to date them. Previous studies had implied that H. erectus overlapped with our species, but most now agree that this was not the case. In 2011 a team led by Susan Antón of New York University concluded that the last H. erectus lived between 143,000 and 546,000 years ago – significantly older. Though there was a huge margin of uncertainty it was still before modern humans arrived in the area. A team led by Kira Westaway of Macquarie University in Sydney, Australia, has now narrowed down the age. The key was that the fossils were found in one of a series of terraces formed by the river. The higher terraces are older and lower ones are younger, so by dating each of the terraces they could identify a window of possible ages for the remains.

12-18-19 Homo erectus: Ancient humans survived longer than we thought
An ancient relative of modern humans survived into comparatively recent times in South East Asia, a new study has revealed. Homo erectus evolved around two million years ago, and was the first known human species to walk fully upright. New dating evidence shows that it survived until just over 100,000 years ago on the Indonesian island of Java - long after it had vanished elsewhere. This means it was still around when our own species was walking the Earth. Details of the result are described in the journal Nature. In the 1930s, 12 Homo erectus skull caps and two lower leg bones were found in a bone bed 20m above the Solo River at Ngandong in central Java. In subsequent decades, researchers have attempted to date the fossils. But this proved difficult because the surrounding geology is complex and details of the original excavations became confused. In the 1990s, one team came up with unexpectedly young ages of between 53,000 and 27,000 years ago. This raised the distinct possibility that modern humans overlapped with Homo erectus on the Indonesian island. Now, researchers led by Prof Russell Ciochon of the University of Iowa in Iowa City opened up new excavations on the terraces beside the Solo River, reanalysing the site and its surroundings. They have provided what they describe as a definitive age for the bone bed of between 117,000 and 108,000 years old. This represents the most recent known record of Homo erectus anywhere in the world. "I don't know what you could date at the site to give you more precise dates than what we've been able to produce," Prof Ciochon told BBC News. Prof Chris Stringer, research leader on human evolution at London's Natural History Museum, who was not involved with the work, commented: "This is a very comprehensive study of the depositional context of the famous Ngandong Homo erectus partial skulls and shin bones, and the authors build a strong case that these individuals died and were washed into the deposits of the Solo River about 112,000 years ago. "This age is very young for such primitive-looking Homo erectus fossils, and establishes that the species persisted on Java for well over one million years."

12-18-19 I'm testing an experimental drug to see if it halts Alzheimer's
Steve Dominy led a landmark study that linked gum disease bacteria to Alzheimer's disease. He tells New Scientist why we should stop treating medicine and dentistry separately. IN JANUARY, we broke the news that we may finally know what causes Alzheimer’s disease. For decades, it had been thought that the condition is caused by a protein called beta-amyloid going awry in the brain. But in 2019, evidence pointed the finger elsewhere: at Porphyromonas gingivalis, a type of bacteria involved in gum disease. Francisco, suggests that beta-amyloid is a symptom, not a cause of the condition. Instead, it may be the toxins released by P. gingivalis, called gingipains, that result in the brain damage that brings on the disease. The hope is that blocking gingipains may at last lead to effective treatments. I caught up with Steve Dominy, head of science at Cortexyme, to find out what has happened since the findings were published. What was the reaction to your study linking Alzheimer’s to Porphyromonas gingivalis? The response has been tremendous. A few days after it came out, we’d been invited to present the work at three big international Alzheimer’s conferences. By the following week, we’d been contacted by labs around the world wanting to collaborate. Some researchers have expressed doubts about the work, including those who have long thought beta-amyloid is to blame. It’s never easy to challenge conventions in science. But when we were able to show our data, and the depth of the evidence, to people at conferences, they became very enthusiastic. Some of the leading figures working in Alzheimer’s clinical trials have now joined our clinical advisory board. Are you conducting clinical trials now? We are testing our experimental drug, COR388, which blocks gingipains, to see if it improves symptoms. We are enrolling up to 570 people with mild to moderate Alzheimer’s at 95 centres across the US and Europe, and randomly assigning them to get the drug or a placebo. The results won’t be back until late 2021.

12-18-19 Drug that restricts overactive immune systems could help treat lupus
A drug that stops the body’s overactive immune system could be key to treating lupus. This would be only the second new drug for the autoimmune condition in 60 years. Around 5 million people around the world are affected by lupus, a condition that causes the body’s immune system to attack healthy organs and results in skin rashes, joint and muscle pain, fatigue and early death. There is no cure, and doctors often rely on therapies from the 1950s to treat symptoms, says Eric Morand of Monash University, Australia. One in 10 people diagnosed with the disease, typically young women, will die within a decade after diagnosis. A growing body of evidence suggests that lupus is linked to producing too many molecules called type 1 interferons, which are involved in regulating the body’s immune system. This prompted Morand and his colleagues to study the effects of anifrolumab, a drug that binds to type 1 interferon receptors and stops the molecule from overstimulating the immune system. They randomly assigned 362 people with moderate to severe symptoms of lupus to receive a 300-milligram injection of either a placebo or anifrolumab every four weeks for almost a year. The benchmark for success was if all of a participant’s organs that displayed signs of the disease at the beginning of the study improved and there were no flare-ups over the year. They found that 48 per cent of participants taking the drug achieved this, compared with 32 per cent taking the placebo. In addition, 52 per cent of those who were taking steroids for the condition were able to reduce the dose, compared with 30 per cent in the control group. This is important because the steroids commonly have side effects such as weight gain, osteoporosis, skin fragility and infections.

12-18-19 The sparkling history of tonic, from medical miracle to G&T essential
The story of how gin and tonic came together fizzes with adventure, discovery, imperial ambition, biopiracy and a generous splash of fake news. LIVER feeling torpid? Nerves debilitated? Stomach weak? Do as the Victorians did and pour yourself a drop of the soft stuff: a tongue-tingling glass of tonic water. Best known today as one half of the ultimate English cocktail, it started out as a drink to revitalise the body and revive the spirits. Now, its sparkling story has been revealed, thanks to two tonic-tippling botanists. On a blistering August afternoon – very definitely a gin-and-tonic sort of day – I headed to the Royal Botanic Gardens, Kew to meet Kim Walker and Mark Nesbitt. I soon found myself in the blissfully cool interior of a temperature-controlled storehouse. There, among Kew Gardens’ vast assemblage of botanical treasures, is the world’s largest collection of bark from cinchona trees, the source of tonic’s most vital ingredient: quinine. Rack after rack of floor-to-ceiling shelves hold a thousand bundles of bark along with bottles, packets and jars of cinchona seeds, powders and extracts. Walker and Nesbitt have scoured this collection and Kew’s archives to trace the evolution of tonic water for their new book, Just the Tonic: A natural history of tonic water . Both the taste and the fizz, it turns out, are rooted in medicine. It is a tale of discovery, adventure, imperial ambition and biopiracy, with a generous garnish of myth. Cinchona trees are native to South America. There are 25 species (the 25th discovered only in 2013), all restricted to cloud forests strung along the eastern slopes of the Andes from Colombia to Chile. The trees’ bark contains dozens of bitter alkaloids, including quinine. In nature, quinine’s job is to deter hungry herbivores. In tonic, it provides the characteristic bitter flavour and refreshing astringency. But for almost 300 years, it was the only cure for malaria known in the West.

12-18-19 Reindeer's real superpowers could help us beat depression and cancer
So what if Rudolph can’t really fly? He and the herd have some truly amazing evolutionary adaptations that could inspire new treatments for human diseases.AS ANY young child knows, reindeer have a special superpower: they can fly. Or, at least, Rudolph and his eight sleigh-towing pals can. Reindeer first took to the skies in 1823, when Clement Clarke Moore published Twas the Night Before Christmas. He is said to have got his inspiration from the Sami people of northern Europe, whose shamans conjured up flying reindeer while in magic mushroom-induced trances. Unfortunately, that’s all bunkum – even the bit about the Sami. But who needs fiction? Reindeer have real-world superpowers. The animals have evolved a whole range of amazing innovations that let them not just survive but thrive in the frigid Arctic. Their eyes change colour like living sunglasses, from gold in summer to blue in winter. They see the world in glorious ultraviolet. They can switch their body clocks on and off, produce lots of vitamin D even in limited sunlight and grow antlers up to a metre long in just a few months. What’s more, we might be able to borrow some of those abilities. Discovering more about Rudolph could lead to new ways of tackling jet lag, insomnia and cancer, and even allow us to grow new limbs. Thanks to recent work revealing the genetic underpinnings of reindeer’s unusual traits, their superpowers could one day be ours. Nearly 5 million reindeer roam the frozen north, from Alaska to Siberia and Greenland. The biggest group, containing about half a million animals, is the Taimyr herd of the Siberian tundra. Also known as caribou in North America, these lichen-eating ruminants are the only deer species to have been tamed by humans and about half are domesticated. On the Norwegian islands of Svalbard, males of the smallest subspecies weigh no more than 90 kilograms. In the forests of Finland, a stag can tip the scales at 250 kilograms.

12-18-19 The big guide to small talk – a scientific masterclass on conversation
Ditch the phone, don't stand too close and strive for optimal eye contact: the evidence-based approach to painless holiday schmoozing. “CONVERSATION should be like juggling,” wrote Evelyn Waugh in Brideshead Revisited. “Up go the balls and the plates, up and over, in and out, good How many of us feel that we regularly manage those acrobatics with aplomb? Whether it is the work Christmas party or a family gathering, the holiday season forces even the most unsociable of us to leave our shells and make small talk. Particularly when we are meeting new people, many of us leave conversations with the distinct feeling that we could have made a better impression. If that sounds familiar to you, I have two pieces of good news. The first is that the reality is unlikely to be bad as your fears, with studies showing that we consistently underestimate how well we are perceived by others, a phenomenon called the “liking gap”. The second is that psychological research can offer us some definitive tips on the art of conversation. From the etiquette of eye contact or how much personal space is appropriate, to the most tactful way to make an exit should the conversation go south, these findings will help you to present your best self at any social occasion. If you want to make a better first impression, one of the most important things to understand is that your words matter less than the general backdrop of feelings you and your interlocutor may be having, many of which are out of your control. Even the weather can influence someone’s opinion of you. But you can avoid subtle behaviours that may worsen someone’s mood. Consider interpersonal distance. We have all met people who get too close for comfort, but you don’t want to feel like you are shouting across a football pitch, either. The optimum space while conversing, according to a study of nearly 9000 people in 42 countries, ranges from about 40 centimetres to three times that, depending on the person’s culture and the nature of the relationship between you, among other factors.

12-18-19 Martin Rees: We will become a new species by expanding beyond Earth
Heading into deep space will lead to a new species of human evolving, says the UK Astronomer Royal - and could pave the way to immortals who can conquer the galaxy. THIS year marked the 50th anniversary of the most iconic moment of the space race: Neil Armstrong’s “small step” onto the moon on 21 July 1969. Many of us who viewed those grainy TV images live expected it to be just a beginning, and that there would have been footprints on Mars long before now. But the heroics of the Apollo missions are ancient history to young people today. After the US had beaten the Soviet Union to the moon, there was no call to sustain the huge outlay on the space race, which at its peak consumed 4 per cent of the US federal budget. Since 1972, no one has got beyond the International Space Station’s orbit, just 400 kilometres up. Yet a half century on, the next instalment of the space race is beginning. China, which landed the first probe on the lunar far side in January this year, plans to send people to the moon. India, which sent a rocket there this year, dreams of doing likewise. The Trump administration in the US proposes creating a lunar base as a step towards sending humans to Mars. Elon Musk and Jeff Bezos are developing rockets to take people to deep space through their ventures SpaceX and Blue Origin. If any of these plans come off, the 2020s could be when Apollo’s promise is finally fulfilled, and humanity establishes its first permanent presence beyond Earth orbit. That raises wider questions about the motives and goals of space exploration – and what the ultimate destiny of our species might be, here on Earth and perhaps far beyond. Space exploration never really went away, of course. We routinely use satellites for communication, navigation and environmental monitoring. Rovers have been sent to the surface of Mars, while the European Space Agency’s Rosetta mission put a lander on a comet. NASA’s Cassini probe spent 13 years exploring Saturn and its moons. NASA’s New Horizons mission gave us our first glimpse of Pluto, having travelled 13,000 times the distance to the moon.

12-18-19 DNA from 6000-year-old chewing gum reveals how an ancient woman lived
She dined on duck, eels and hazel nuts, before settling down to a spot of tool-making, using birch bark pitch as a glue for sticking stone blades to wooden handles. The dark-haired, dark-skinned woman chewed the pitch for a while to make it more pliable, then for some reason spat out a wad without using it. Six thousand years later archaeologists have extracted DNA from the discarded lump to shed light on the woman’s diet, appearance, and ancestry. They have named her Lola, as it was found on the island of Lolland, part of modern-day Denmark. “It’s amazing – I know what she’s been eating, what colour her eyes were, what colour her hair was,” says Søren Sørensen at the Museum Lolland-Falster, which is running the excavation. “It’s like standing face to face with a stone age person.” Analysis of DNA from ancient human remains such as bones and teeth has been growing in recent years, but this work is among the first to analyse prehistoric “chewing gum”. Birch pitch, made by heating the tree’s bark until it forms a black tar, was used by many ancient people as glue, for instance to stick arrow heads to their shafts or knife blades to their handles. Small lumps of pitch have been recovered from several prehistoric sites across Europe, often with clear tooth marks. Chewing the goo would have made it more pliable. But it also has antiseptic properties so people may have chewed it to help heal mouth wounds, or even for the same reasons we chew gum today – out of hunger or boredom. Some of the indentations are made by the small teeth of children. “Once you see kids’ teeth imprints you think it’s no different to today when kids go around spitting out chewing gum,” says Natalia Kashuba of the University of Oslo. “I want to believe that it’s also recreational, but there’s no way to know.”

12-18-19 DNA from 5,700-year-old ‘gum’ shows what one ancient woman may have looked like
Chewed birch pitch could be an overlooked source of ancient genetic material, researchers say. Fossilized bones and teeth aren’t the only source of ancient human DNA. The genetic material also sticks around in birch pitch “chewing gum,” which can hold enough DNA to piece together the genetic instruction books, or genomes, of long-dead people, researchers report December 17 in Nature Communications. By analyzing a 5,700-year-old chewed wad of pitch from Denmark, the team obtained the genome of an ancient woman, and determined that she probably had blue eyes, dark skin and dark hair. Ancient humans likely chewed the pitch — made by heating birch bark — to make it pliable, working cells from the mouth deep into the sticky substance. Birch pitch is relatively resistant to bacteria and viruses as well as water, which would have protected the DNA from decay, the researchers say. The team also recovered DNA from microbes that may have lived in the woman’s mouth, including from older versions of Epstein-Barr virus, which causes mononucleosis, and bacteria that can cause pneumonia or gum disease. Duck and hazelnut DNA were also identified, and may be remnants from a recent meal the woman ate before popping a piece of pitch into her mouth. Scientists have gleaned information about ancient humans’ mouth microbes and diets (SN: 10/4/17) from dental plaque in fossilized teeth (SN: 3/8/17). “But that’s been built up over many years,” says study coauthor Hannes Schroeder, a geneticist at the University of Copenhagen. “With the chewing gum, it’s kind of like a snapshot of one moment in time.”

12-18-19 DNA from Stone Age woman obtained 6,000 years on
This is the face of a woman who lived 6,000 years ago in Scandinavia. Thanks to the tooth marks she left in ancient "chewing gum", scientists were able to obtain DNA, which they used to decipher her genetic code. This is the first time an entire ancient human genome has been extracted from anything other than human bone, said the researchers. She likely had dark skin, dark brown hair and blue eyes. Dr Hannes Schroeder from the University of Copenhagen said the "chewing gum" - actually tar from a tree - is a very valuable source of ancient DNA, especially for time periods where we have no human remains. "It is amazing to have gotten a complete ancient human genome from anything other than bone,'' he said. The woman's entire genetic code, or genome, was decoded and used to work out what she might have looked like. She was genetically more closely related to hunter-gatherers from mainland Europe than to those who lived in central Scandinavia at the time, and, like them, had dark skin, dark brown hair and blue eyes. She was likely descended from a population of settlers that moved up from western Europe after the glaciers retreated. Other traces of DNA gave clues to life at Syltholm on Lolland, an island of Denmark in the Baltic Sea. The DNA signatures of hazelnut and mallard duck were identified, showing these were part of the diet at the time. "It is the biggest Stone Age site in Denmark and the archaeological finds suggest that the people who occupied the site were heavily exploiting wild resources well into the Neolithic, which is the period when farming and domesticated animals were first introduced into southern Scandinavia," said Theis Jensen from the University of Copenhagen. The researchers also extracted DNA from microbes trapped in the "chewing gum". They found pathogens that cause glandular fever and pneumonia, as well as many other viruses and bacteria that are naturally present in the mouth, but don't cause disease.

12-17-19 Light therapy device helps improve some symptoms of dementia
Daytime exposure to bright light may help improve sleep and relieve some dementia symptoms in older people by strengthening their circadian rhythms. These 24-hour biological cycles enable our bodies to switch tasks and recuperate by synchronising specific activities, including sleep, with day and night. As we age, the lenses of our eyes grow cloudier, meaning less light reaches photoreceptive cells in the retina that connect to the body’s master clock in the brain, called the suprachiasmatic nucleus. That can be problematic, as daylight helps keep our biological rhythms in line with external time. It is even worse for elderly care home residents who rarely venture outside, and who are often exposed to light at night, to help keep them safe. “When people are in constant dim light, their bodies don’t know what day and night is,” says Mariana Figueiro at the Lighting Research Center in New York. Many elderly care home residents experience insomnia and disrupted circadian rhythms, which may present as excessive daytime sleepiness, nocturnal wandering and sundowning – agitation and irritability during late afternoon and early evening. Previous research has suggested that boosting light levels during daylight hours might reduce the rate of cognitive deterioration among care home residents with dementia. However, others have tried to replicate these findings with mixed results. One problem is ensuring that enough light is delivered into people’s eyes. Since many care home residents with dementia spend their daytimes seated in communal areas, Figueiro and her colleagues designed a light table that directs light upwards. These were installed in eight US care homes, along with additional light boxes and floor lamps to deliver lighting that was bright enough and contained enough blue-spectrum light to activate the circadian system. They were used by 46 residents with moderate to late-stage dementia for four weeks.

12-17-19 Mice watching film noir show the surprising complexity of vision cells
Only about 10 percent of these cells behaved as researchers expected. The eerie opening shot of the slow drive of a bomb-carrying car in Orson Welles’ 1958 Touch of Evil prompts strong reactions in film watchers. Now reactions in the brains of an unusual audience — mice — offer a major twist in our understanding of how brain cells parse visual scenes. Scientists used to think that each of the many cells in the brain’s visual system primarily handles a single job, such as responding to a black and white contrast. But a study published December 16 in Nature Neuroscience does away with that simplicity. Researchers including Saskia de Vries, a neuroscientist at the Allen Institute for Brain Science in Seattle, used a powerful microscope to study 59,610 brain cells in the visual systems of live mice, through openings in their skulls. The researchers then watched whether these cells responded to (or ignored) a lineup of visual input, including clips from Touch of Evil and simpler images, such as drifting black stripes and a still picture of a butterfly. The way that the nerve cells, or neurons, behaved was a surprise. Overall, only about 10 percent of the neurons studied responded as the researchers expected, based on data from earlier studies. “The remaining neurons don’t look like what’s going on in the textbook,” de Vries says. Across the trials, many cells responded to several kinds of visual scenes, such as drifting lines and movies, but unreliably. Some cells responded to all of the images. And a large group of cells — about a third of all tested — responded to none of the visual scenes, the researchers found. “What, then, do these neurons do?” the researchers ask in their paper. More experiments may offer clues, but for now, these mystery neurons’ roles are still in the dark.

12-17-19 Koalas and apes have evolved similar ways of walking in trees
Koalas clamber about in trees much like primates, despite being separated from them by tens of millions of years of evolution. “They are the closest thing we have to primates in Australia,” says Christofer Clemente at the University of the Sunshine Coast in Sippy Downs, Australia. Koalas are marsupials that carry their young in pouches. Although marsupials are mammals, their ancestors split from those of other mammals such as dogs and monkeys during the dinosaur era. Isolated in Australia for millions of years, marsupials like koalas have evolved independently. There were no primates in Australia before humans arrived. Despite koalas’ fame, very little was known about how they walk and climb, says Clemente. His team filmed six koalas living in Queensland Zoo, in a habitat that mimicked the eucalyptus forests where wild koalas live. The koalas were filmed both in trees and on the ground. Marsupials often bound across land, with both hind feet hitting the ground at the same moment. But Clemente and his team found that koalas moved more like primates in the trees. Many mammals have a gait in which the two legs on the same side of the body move together, supporting each other. “However, primates, and now koalas, show a slightly different gait,” says Clemente. Diagonal pairs of legs move together, so the front left moves with the back right. By itself, this isn’t unique: cats also do it, for example. But in primates and koalas, if the rear right leg touches down on the ground, the next foot to be put down will be the front left, and vice versa. This gait has been seen in only a few animals other than primates, including kinkajou and woolly opossum. “We think this is linked to stability on narrow supports,” says Clemente. Always having one leg holding a branch on each side may make koalas less likely to wobble to one side and fall off.

12-17-19 Giant prehistoric caiman had extra hip bone to carry its weight
A prehistoric caiman, which weighed up to three tonnes, had an extra hip bone and upright shoulders to help it carry its weight on land, scientists say. Purussaurus mirandai could grow up to 10m (32ft) in length and lived in the swamps and rivers of what is now Venezuela. An international team of scientists says its extra vertebra and shoulder alignment meant it could move on land. The team, led by Dr Torsten Scheyer of the Palaeontological Institute and Museum of Zurich, studied fossils found in the badlands of Venezuela. They found that the now-extinct giant caiman had an extra vertebra in its sacrum, the lower part of its spine. Its shoulder girdle was also aligned with the action of gravity, allowing it to better move its massive weight. "Our findings are important because they help show how development can be altered in order to enable biomechanical changes as animals evolve into larger body sizes," Prof John Hutchinson of The Royal Veterinary College in London said. Dr Schreyer said the discovery "broadens our knowledge of what animals can do in evolution". "These old bones show us once again that the morphological variation seen in animals that are long extinct extends well beyond that of what is known in living animals," he said. Purussaurus mirandai is the only crocodylian that has been found to have the extra vertebra in its sacrum, the scientists said.

12-16-19 Anti-ageing drug rejuvenates the mouths and oral microbiome of mice
A transplant drug with anti-ageing properties has been shown to rejuvenate the oral health of old mice. The drug, called rapamycin, regenerated the bone in which teeth are embedded, restored the mouth microbiome to a youthful state and reduced inflammation. It is the first time any treatment has been shown to rejuvenate oral health, says team leader Matt Kaeberlein at the University of Washington in Seattle. “We could actually see spots where new bone was growing around the teeth.” Two-thirds of elderly people have gum disease and no existing treatment reverses the process, says Kaeberlein. What’s more, gum disease is linked to a higher risk of other conditions, including dementia, diabetes and heart disease. Some researchers think gum disease is the cause of Alzheimer’s, as New Scientist reported earlier this year. This suggests that restoring oral health could have much wider benefits. “It’s clear to me that this could be immensely important,” says Kaeberlein. But it isn’t clear if rapamycin has the same effect in humans. Even if it does, the drug can have many undesirable side effects. It suppresses the immune system, which is why its main use is in preventing transplanted organs from being rejected. Rapamycin has also attracted interest for its anti-ageing effects: it can extend the lives of several animals, including mice and fruit flies, by around 10 per cent. Kaeberlein started looking at its effect on the mouth when Jonathan An, who had previously studied dentistry, joined his team. The researchers found that mice given rapamycin all their lives had more bone around their teeth. So they gave mice aged 20 months – elderly in mouse terms – food with added rapamycin for eight weeks, and compared their oral health with that of mice not given the drug. The team saw bone growth in the mice’s mouths, as well as a decline in disease-associated bacteria that become more common in older animals. These include Porphyromonas gingivalis, which is a suspected cause of Alzheimer’s.

12-16-19 Measles got a foothold in the United States this year and almost didn’t let go
Areas of low vaccination are blamed for the virus’s almost 12-month stay. n 2019, measles sickened more people in the United States than in any year since 1992. As of December 5, there were 1,276 illnesses reported in 31 states. Two outbreaks in New York accounted for the lion’s share: more than 75 percent of the cases. The New York outbreaks, which began in the fall of 2018, ran almost long enough to strip the United States of its measles elimination status, which it achieved in 2000. To receive that designation from the World Health Organization, a country must go a year without the disease spreading continuously in an area within its borders. There have been U.S. outbreaks since 2000 — most notably, 667 cases in 2014 — but none had threatened to undo elimination (SN Online: 10/4/19). The outbreak in New York City ended on September 3. The other New York outbreak, in Rockland and neighboring counties, ended in early October. “The best way to stop this and other vaccine-preventable diseases from gaining a foothold in the U.S. is to accept vaccines,” Robert Redfield, director of the U.S. Centers for Disease Control and Prevention in Atlanta, said in an October 4 statement announcing that the nation was holding on to its elimination status. Many other countries struggled with measles outbreaks this year (SN: 6/8/19, p. 22). As of November 17, Congo had the largest outbreak, with an estimated 250,000 measles cases and more than 5,000 deaths, mostly children under 5. Samoa, with immunization rates as low as 31 percent, was hit hard late in 2019, with more than 3,700 cases and dozens of deaths.

Measles flare-up! U.S. measles cases by year.

12-16-19 Tiny machines made of DNA origami may make antibiotics work better
Origami isn’t usually thought of as a weapon – but it can be deadly when it is made of DNA. Tiny devices made from intricately folded DNA strands can boost the potency of antibacterial chemicals by bringing individual molecules into direct contact with microbes. When tested on two common kinds of bacteria, the folded DNA slowed their growth rate. Ioanna Mela at the University of Cambridge says the approach could be directed against any kind of microbe. “This is proof of principle,” she says. DNA is best known for storing our genetic information, but it has other useful properties. One is that it can be folded into complex 3-D structures to make any desired pattern, known as DNA origami. Another is that small lengths of DNA can be designed to have the exact shape needed to bind to other biological molecules, like a key fitting into a lock. Mela’s team combined these two functions to create a bacteria-killing machine in the form of a flat platform of DNA with five wells, each loaded with two molecules of lysozyme, an antibacterial compound found in body fluids such as tears. Sticking out from the edges of the platform are many short lengths of DNA designed to bind to E. coli or Bacillus subtilis bacteria.The idea is that the platforms lock on to bacteria and hold them close to the lysozyme, increasing its potency. Sure enough, when bacteria were exposed to the platforms, they grew more slowly than when exposed to the antibacterial compound alone. Using the approach for an antibiotic drug would allow lower doses to be given, reducing side effects for individuals and slowing the rise of antibiotic resistance in general, says Mela. The team will also try adding more than one kind of antibiotic to each well. “We can attach or take away active components from the same nanostructure without much time or cost constraints,” says Mela.

12-15-19 How to get the most out of the final months of life
A sociologist explains the importance of recognizing death as a normal part of life to empower people to discuss difficult issues. e are all going to die — and most of us will be able to see death coming, months or even years before it happens. That foreknowledge means we should embrace the end of life as a distinct life stage, just like childhood, adolescence, and maturity, says Deborah Carr, a sociologist at Boston University. In the 2019 Annual Review of Sociology, Carr and her co-author, Elizabeth Luth of Weill Cornell Medicine in New York, explore how to make the most of this final stage in our lives. Carr spoke with Knowable about how to find a good death. In past centuries, people tended to die younger, but more important, they tended to die quickly after they became ill. The end of life was basically a week, if that. People died at home. Today, with people dying of conditions like dementia and cancer, someone can experience a month or 10 years between diagnosis and actual death. And today, ventilators and feeding tubes allow people to prolong the length of their life, even if not the quality of life. So it's a longer and more uncertain stage than in the past. I think that is one of the main objectives. And that's a new construct. In the days when people died suddenly, death was really a discrete event. You didn't have to find ways to soothe them or provide music or other amenities. Today, because people tend to die over prolonged time periods, there's a real emphasis on ensuring that the quality of that experience, whether it's a week, a month, or six months, is as positive as possible. A good death typically has several pillars. First and foremost is freedom from pain. A sizeable portion of dying patients have physical pain and difficulty breathing. So the use of painkillers, palliative care, devices that allow someone to breathe comfortably, is very important. Another is self-determination. Dying patients and their families want to have some control over the process. They want to choose where they die: at home or in a hospital. They want to choose what kind of treatment they get, whether they get life support. And the third pillar is a broad category called death with dignity. People want to be treated as a whole person. They want their spiritual and psychological needs met. People even think about planning a funeral that has their favorite music and foods. They want to die being the human being they were in their younger years.

12-14-19 Is the axolotl our greatest hope of regeneration?
Science has been chopping up salamanders for more than 200 years with the aim of understanding the mechanics of their marvels, but more recently with the hope of someday replicating those marvels in ourselves. It has long been understood, and by cultures too various to list, that salamanders have something of the supernatural about them. Their name is thought to derive from an ancient Persian vocable meaning "fire within," and for at least 2,000 years they were believed to be impervious to flames, or even capable of extinguishing them on contact. Aristotle recorded this exceptional characteristic, as did Leonardo da Vinci. The Talmud advises that smearing salamander blood on your skin will confer inflammability. Not so. But the intuition that salamanders possess fantastical powers is not unfounded. Like earthbound immortals, salamanders regenerate. If you cut off a salamander's tail, or its arm, or its leg, or portions of any of these, it will not form a stump or a scar but will instead replace the lost appendage with a perfect new one, an intricacy of muscle, nerve, bone, and the rest. It will sprout like a sapling. Science has been chopping up salamanders for more than 200 years with the aim of simply understanding the mechanics of their marvels, but more recently with the additional aim of someday replicating those marvels in ourselves. Might salamanders be the great hope of regenerative medicine? The salamander in which regeneration is most often studied is an odd and endearingly unattractive Mexican species known as the axolotl. In addition to its limbs and extremities, the axolotl is known to regrow its lower jaw, its retinae, ovaries, kidneys, heart, rudimentary lungs, spinal cord, and large chunks of its brain. It heals all sorts of wounds without scarring. The axolotl also integrates the body parts of its fellows as if they were its own, without the usual immune response, and this peculiar trait has facilitated some of the more grotesque disfigurements it's endured in the name of science. In experiments after the Second World War, East German scientists grafted small axolotls crosswise through the backs of larger ones. The animals' circulatory systems came to be linked, and the researchers hailed the conjoined mutants as triumphs of collectivism. While the axolotl can rebound from almost any bodily humiliation, it seems that humankind is proving too much for it: we have all but destroyed its natural habitat, and, outside of laboratory aquaria, it is nearly extinct.

12-14-19 Surplus chromosomes may fuel tumor growth in some cancers
Without that extra genetic material, cancerous cells form fewer tumors in mice. Some cancers are addicted to having extra chromosomes, a study in mice suggests. Cells usually have just two copies of each chromosome — one inherited from mom and one from dad. But about 90 percent of cancer cells have additional chromosomes, a condition called aneuploidy. Certain types of cancer cells often carry a third copy of a particular chromosome or part of a chromosome. For instance, more than half of colorectal tumors have a surplus chromosome 13, and more than 40 percent carry an extra chromosome 7 or the long arm of chromosome 8 (SN: 5/31/18). Stocking spare copies of chromosomes has been associated with poorer outcomes for patients compared with patients whose cancers have the usual two copies. It turns out that those extra doses of genetic material are necessary for the cancer cells to keep growing, cancer geneticist Jason Sheltzer reported December 11 at the joint annual meeting of the American Society for Cell Biology and the European Molecular Biology Organization. Put another way, cancer tumors are addicted to the bonus chromosomes, he says. The idea of “addicted” cancer cells isn’t completely new. Scientists have known for decades that cancer cells can be addicted to altered versions of certain genes, meaning that those genes are required for the continued cancerous growth of the cells. As for chromosomes, researchers have speculated for more than a century that some cancers have particular chromosome surpluses that spur growth. But the ability to specifically delete specific chromosomes to test the idea is new, says Beth Weaver, a cancer cell biologist at the University of Wisconsin–Madison, who was not involved in the work.Description

12-13-19 Clean teeth, healthy heart
If you want to reduce your risk of heart failure, always remember to brush your teeth. That’s the conclusion of a new study from South Korea, reports The Times (U.K.). Researchers examined 161,286 people, ages 40 to 79, with no history of heart problems. Over a study period lasting an average of 10½ years, 3 percent of participants developed atrial fibrillation—an irregular or fast heartbeat—and 4.9 percent suffered heart failure. Overall, those who brushed their teeth three or more times a day were 10 percent less likely to suffer from atrial fibrillation, and 12 percent less likely to have heart failure. People who had lost most of their teeth had a 35 percent increased risk of heart failure. The researchers say that poor oral hygiene allows bacteria to build up in “the pocket between the teeth and gums,” and then seep into the bloodstream. This can cause inflammation, part of the body’s defense mechanism as it battles the germs, and over a long period that can affect the cardiovascular system and the brain.

12-13-19 Were Neanderthals just unlucky?
It might be time to cross Homo sapiens off the list of suspects in the Neanderthals’ extinction. Our thick-browed cousins died off some 40,000 years ago, about the same time modern humans were leaving Africa and entering Neanderthal stomping grounds in Europe and Asia. That timing led researchers to assume that humans drove Neanderthals out of existence, by outsmarting or outcompeting them. In a new study, researchers at Eindhoven University of Technology in the Netherlands created a simulation of the Neanderthal population—which likely numbered no more than 70,000 when humans arrived—based on DNA records. They then ran models on how that population would have coped with three species vulnerabilities: inbreeding, which can cause harmful genetic mutations; the difficulty of finding a mate in a small population; and chance events such as an unusually high death rate in any given year. “We ran those models for 10,000 years and looked at whether they would go extinct or not,” study leader Krist Vaesen tells New Scientist. “We found that these three processes were enough to do the trick.” Still, the study does not definitively prove that Homo sapiens weren’t responsible for the Neanderthals’ demise, says archaeologist Penny Spikins, “so it may be a little premature to entirely absolve ourselves of ‘survivor’s guilt.’”

12-12-19 People in Japan are wearing exoskeletons to keep working as they age
Older people in Japan are strapping on exoskeletons to help meet the physical demands of their jobs and remain in the workforce longer. Japan’s population is rapidly ageing, with a record 28 per cent of people aged 65 or older. This has led to a shortage of workers, particularly in manual labour industries such as construction, manufacturing and farming. To encourage older people to stay in or move into these industries, several tech companies in Japan have developed exoskeleton suits that make it easier to lift and carry heavy objects. “We have no option – elderly people need to stay at the workplace,” says Daigo Orihara at Innophys, which makes one model called the Every Muscle Suit. The suit, which is worn like a backpack, doesn’t contain any batteries or motors and weighs less than 4 kilograms. When users put it on, they squeeze a hand pump 30 times to fill the suit’s “artificial muscles” with pressurised air. Once pumped up, the artificial muscles allow people to lift up to 25 kilograms, says Orihara. They need to be reinflated with the hand pump every day or two, he says. Innophys has sold 4000 of the suits – which cost about £1000 ($1300) – since releasing them in April 2018. They are currently being used by one of Japan’s biggest whisky companies to help workers lift barrels, by nursing homes to help staff lift residents in and out of bed, as well as by food manufacturers and construction companies. Older people have told the company that the suits have allowed them to work for longer, says Orihara. “One client is a family-owned company which makes and sells pickled radish and uses heavy weights in the process of production,” he says. “The father is in his 70s and was supposed to retire but is still working with our muscle suit,” he says.

12-12-19 Prions clog cell traffic in brains with neurodegenerative diseases
Clumps of these proteins may contribute to nerve death by causing mitochondria to crash. Clumps of misfolded proteins cause traffic jams in brain cells. Those jams may have deadly consequences in neurodegenerative diseases. Clusters of prions block passage of crucial cargo along intracellular roadways in brain cells, cell biologist Tai Chaiamarit of the Scripps Research Institute in La Jolla, Calif., reported December 10 at the joint annual meeting of the American Society for Cell Biology and the European Molecular Biology Organization. Prions, misshaped versions of a normal brain protein, clump together in large aggregates that are hallmarks of degenerative brain diseases, such as mad cow disease in cattle, chronic wasting disease in deer and Creutzfeldt-Jakob disease in people. It’s unclear why those clumpy proteins are so deadly to nerve cells called neurons, but the new study may provide clues about what goes wrong in these diseases. Axons, the long stringlike projections of nerve cells that carry electrical signals to other nerves, are the sites of prion traffic jams, Chaiamarit and colleagues found. As more prions clump together, they cause swollen bulges that make the axon look like a snake that has just swallowed a big meal. Through a microscope, Chaiamarit and colleagues saw mitochondria being transported toward the cell’s furthest reaches derailed at the bulges. Mitochondria, cells’ energy-generating organelles, are carried outbound from the main body of the cell by a motor protein called kinesin-1. The protein motors along molecular rails called microtubules. A different motor protein, dynein, transports mitochondria back toward the cell body along those same rails.

12-12-19 DNA may hold clues to extinct animal lifespan
Scientists have calculated the lifespans of extinct animals, including ancient humans, from the DNA they left behind. Our extinct "cousins", the Neanderthals and Denisovans, reached the ripe old age of 38 years, less than half that of modern life expectancies. Woolly mammoths, meanwhile, lived to about 60. Australian researchers also analysed the DNA of living species, such as whales, for which few records exist. The bowhead whale could be the longest-lived mammal, reaching more than 250 years of age, they said. Until now lifespan has been difficult to define for many animals, especially long-lived ones. "Knowing the lifespan of an extinct animal can provide insights into their ecology," said Benjamin Mayne of the Commonwealth Scientific and Industrial Research Organisation in Crawley, Australia. "If a species is not reaching their natural maximum life span in the wild it may indicate environmental pressures pushing the species into extinction." The scientists used DNA to estimate the lifespan of a species, looking at changes in stretches of DNA linked to ageing. These "DNA clocks" were used to predict a maximum lifespan for animals living and dead. Calculating the lifespan of our close relatives gives clues to how modern medicine and changes in lifestyle have helped us live longer. In the past 200 years, the average life expectancy of humans has more than doubled. The research can also tell us more about the ecology and evolution of living and extinct species, the protection of threatened species, and sustainable fishing, the scientists say. The research is published in the journal Scientific Reports.

12-12-19 AI genome scanner says Denisovans could live until 38 years old
Artificial intelligence may be able to work out the maximum lifespans of extinct species and early humans. The technique relies on analysing specific regions of DNA that are linked to ageing. Benjamin Mayne at CSIRO, a research organisation in Australia, and his colleagues built an AI to predict the lifespan of different animals. To this the team first trained an AI on the known genomes of 252 species from five classes of animals, including mammals, reptiles and fish, and their maximum lifespans. The AI then narrowed down almost 30,000 DNA regions to just 42 that related to lifespan. This was then used to create a formula that can convert these 42 regions into a prediction of maximum lifespan. The team tested the AI on some extinct species. It estimated that the woolly mammoth could live for up to 60 years and Denisovans, an ancestor of modern humans, about 38 years. The researchers also found that Pinta Island tortoises could live to be 120 years old, the current known oldest is estimated to be over 100. And the oldest bowhead whale is thought to be 211, but the model predicts the species could live to 268. The formula was off by around four years on average, when compared to animals that we know the maximum lifespan of. However, it also predicted that the maximum lifespan for humans was 38, suggesting the results should be taken with a pinch of salt. Testing the AI with the genomes of animals with known lifespans showed its guesses were off by around four years on average. But we don’t know how well this translates to extinct species – ancient DNA is more degraded and harder to analyse, says Mayne, so the model needs extra information. To come to 60 years for the mammoth, for example, the team had to incorporate the African elephant’s genome.

12-12-19 Flooding Earth’s atmosphere with oxygen may not have needed a triggering event
Just the circulation of basic nutrients may have been enough to affect the balance of gases. Maybe the trigger for the rise of oxygen on Earth was nothing special. Maybe that oxidation didn’t need large tectonic shifts or the evolution of land plants. Instead, the circulation of carbon dioxide, oxygen and phosphorus between Earth’s atmosphere, oceans, rocks and the simplest of photosynthesizing life forms is sufficient to produce the dramatic shifts in atmospheric gases that occurred in Earth’s history, new research suggests. “The [oxygen] transitions we see are driven by Earth’s nutrient cycles,” said Benjamin Mills, a biogeochemist and computer modeler at the University of Leeds in England, who presented the research December 10 at the American Geophysical Union’s annual meeting. The findings, led by Leeds geologist Lewis Alcott, were also published online December 10 in Science. Early Earth’s atmosphere was a steamy mix of water vapor, CO2, ammonia, hydrogen sulfide and methane. Then, about 2.4 billion years ago, oxygen in the atmosphere suddenly skyrocketed, a surge known as the Great Oxidation Event (SN: 2/6/17). After another billion years or so, two more large pulses of oxygen to the atmosphere followed. One, called the Neoproterozoic Oxidation Event, which occurred from about 800 million to 540 million years ago, brought oxygen levels to within 10 to 50 percent of modern levels and oxidated the surface ocean. During a final pulse called the Paleozoic Oxidation Event, from about 450 million to 400 million years ago, oxygen rose to modern levels in the atmosphere and penetrated down into the deep ocean. Such dramatic pulses beg an explanation. Researchers have considered tectonics such as the formation of supercontinents, the uplift and weathering of mountains and the eruption of vast lava fields known as large igneous provinces. Such processes, the idea goes, might have funneled massive amounts of nutrients into the oceans in a short period of time, fueling sudden, world-changing blooms of algae. Other researchers propose that the three stepwise increases correspond to three big evolutionary advances: the rise of photosynthesizing algae, the flourishing and diversifying of those algae and the rise of land plants.

12-12-19 A nearly 44,000-year-old hunting scene is the oldest known storytelling art
The panel was found in an island cave in Indonesia. An Indonesian cave painting that shows wild animals encountering otherworldly hunters represents the oldest known example of art depicting lifelike figures as well as of visual storytelling, researchers say. Discovered in December 2017 on the island of Sulawesi, this roughly 4.5-meter-wide hunting scene was painted at least 43,900 years ago, says a team led by archaeologists Maxim Aubert and Adam Brumm, both of Griffith University in Gold Coast, Australia. Part-human, part-animal hunters depicted in the mural indicate that people at the time believed in supernatural beings, the scientists report December 11 in Nature. “We assume these ancient artists were Homo sapiens and that spirituality and religious thinking were part of early human culture in Indonesia,” Brumm says. wo pigs and four miniature buffalo called anoas, which still inhabit Sulawesi forests, range across the cave art scene. Eight small, humanlike figures with animal characteristics appear to be hunting the painted pigs and anoas with spears or ropes. One hybrid creature sports a tail. Another has a beaklike snout. Mythical human-animal hybrids, also known as therianthropes, often appear in folklore and in fiction of modern societies. Many religions regard therianthropes as gods, spirits or ancestral beings. Figurines of a lion-headed person (SN: 5/19/09) and a woman with exaggerated features previously found in a German cave date to as early as 40,000 years ago, as do flutes made of bone and mammoth tusks found in the same cave (SN: 6/24/09). A drawing of a man with a bird’s head inside France’s Lascaux cave dates to between around 14,000 and 21,000 years ago.

12-11-19 D’oh! Why human beings aren’t as intelligent as we think
Human attempts to define intelligence are largely motivated by a desire to prove we have more of it – but a look at the world around us suggests a different story. INTELLIGENCE has enabled humans to reach for the moon, cure disease and generally dominate this small blue dot of a planet. Arriving at a working definition of intelligence still defeats it, however. It certainly isn’t just IQ. Tests of pattern finding and word matching capture many of the mental skills that correlate with performance in academic exams and in many workplaces. But they fail on other measures such as wisdom, social sensitivity and practical sense. “No single number captures the rich complexity of what it means to be intelligent,” says Rosalind Arden, an intelligence researcher at the London School of Economics. There are things we can say. Intelligence “reflects a broader and deeper capability for comprehending our surroundings – ‘catching on’, ‘making sense’ of things, or ‘figuring out’ what to do”, is one oft-quoted attempt to define it. It puts the ability to learn from experience and change behaviour accordingly at the heart of a quality called general intelligence. This isn’t an exclusively human trait: an octopus’s ability to solve puzzles or an antelope’s talent for assessing the most nutritious grasses is also intelligent behaviour. “Intelligence is the capacity to solve problems relevant to that species,” says Arden. In our unusually big and well-connected brains, general intelligence has morphed into special talents for abstract thinking, detailed forward planning, understanding the minds of others and insight – those “aha!” moments when we connect cause and effect. But we shouldn’t get blown away by our supposedly superior abilities: we share virtually all our intelligence skills with close animal relatives. “Humans are limited by our size, our evolutionary history,” says Arden. “Actually we have the sort of intelligence that would have evolved for a species like us.”

12-11-19 Why it’s time to call time on the ‘nature vs nurture’ debate
How much of our make-up is predetermined by our genes, and how much by our environment? The truth is that we're asking entirely the wrong question. IT IS an age-old debate that crops up everywhere from discussions of gender identity to our propensity to conditions such as obesity. How much is hardwired inside, the inescapable product of our genes, and how much is down to external factors? Trouble is, this nature vs nurture debate is fundamentally wrong-headed. Even before conception, our make-up is influenced by “epigenetic” factors: choices our parents make, chemicals they are exposed to, infections they get. These don’t alter our genetic code, but just how the instructions it contains are carried out – how it is expressed. Environmental factors continue to change how our genes make us tick throughout life. For developmental psychologist Alison Gopnik at the University of California, Berkeley, this constant interplay makes even asking how much we are nature and how much nurture meaningless. “People often think about it as if there’s some kind of formula you could use,” she says. “That’s fundamentally misguided.” In some cases, identical twins grow up to have dramatically different personalities, while in others identical siblings separated at birth turn out to have strikingly similar personalities, mannerisms and more. Even some genetic disorders can be thought of as environmental. Phenylketonuria, for example, inhibits a body’s ability to break down the amino acid phenylalanine, and can cause devastating brain damage. But if the disorder is identified at birth, children can go on to live happy, healthy lives, by taking supplements and adopting a low protein diet. “In one sense, this syndrome is 100 per cent nature, in another it’s 100 per cent nurture,” says Gopnik.

12-11-19 No more goody two shoes: Why true altruism can’t exist
If only the fittest survive, why do good deeds for no return? The enduring mystery of altruism goes to the heart of how evolution does – and doesn't – work. THERE was no doubt that the humpback whale saved the seal’s life, carrying it away on its chest and protecting it with its flipper from the onslaught of the killer whales. It was odd behaviour that marine ecologist Robert Pitman observed in the frigid Antarctic seas back in 2009 – but, it turned out, not uncommon. How you interpret it goes to the heart of an intense evolutionary debate: can any creature ever be truly altruistic? A basic reading of evolution says no, because survival of the fittest means maximising your own reproductive success. Altruism, defined by philosopher Auguste Comte in 1851 as “intentional action, ultimately for the welfare of others, that entails at least the possibility of either no benefit or a loss to the actor”, is simply not a thing. Things that look like it are widespread. Many animals act in ways that reduce their own reproductive success but benefit others. Some social insects, for example, give up reproduction entirely to support the colony. One proposed explanation is kin selection: altruism persists because it helps the close relatives of nicer individuals to reproduce, which passes their own genes on too. Some form of this was probably at play with the humpback whale: by automatically chasing away orcas, regardless of what they were attacking, the humpback increased the survival chances of individuals in its pod. David Sloan Wilson at Binghamton University in New York champions a different idea: group selection. This emphasises the reproductive success not of individuals, but of a whole group. “All you have to do is go up a little bit in scale, and there you have your evolutionary advantage,” he says.

12-11-19 Extinction is a fact of life. Could we stop it – or even reverse it?
The fossil record tells us extinctions happen all the time. The question is what part we play – and whether we could ever bring back creatures like the dinosaurs. WHEN what is now the iconic emblem of extinction finally kicked the bucket, nobody noticed. At that time – around 1662, probably the year a dodo was last seen in the wild – the idea that entire species could be wiped out had never occurred to anyone. Pre-Darwinian biology was in thrall to the idea that animals and plants were perfect and eternal designs of the Creator. Disbelief certainly greeted French naturalist Georges Cuvier in 1796 when he suggested that mammoth, mastodon and giant sloth bones were remains of animals that had died out. Nonsense, snorted the establishment: they were simply living animals that had moved elsewhere. It took time for Cuvier’s killer argument – that if these huge beasts were still around, someone would have seen them – to win out. Where there is life, there is extinction. The fossil record tells us that more than 99 per cent of species that have ever lived are no longer with us. Biologists estimate a “background rate” of about one extinction per million species per year, caused by disease, predation, environmental change and things simply evolving into other things. More dramatic are five mass extinctions documented in the fossil record. During each, more than three-quarters of the planet’s species were lost in just a million years or so – most recently around 66 million years ago, in the event that did for the dinosaurs. Documenting extinction today is trickier. The International Union for Conservation of Nature defines a species as extinct when there is no reasonable doubt it is no longer alive. The most recent recipient of this dubious honour is the Bramble Cay mosaic-tailed rat (Melomys rubicola), a rodent endemic to a tiny dot of land in the Torres Strait just off Papua New Guinea. Last seen in 2009, it was declared extinct in 2015 after three fruitless surveys of a flat, featureless island about the size of five football pitches.

12-11-19 Homo sapiens? Genetic insights suggest we may not really be a species
Are you a human, or a human-Neanderthal hybrid? The concept of the species, one of the most basic in biology, may not be as well-defined as we think. HOMO SAPIENS likes to categorise. Putting things in boxes helps us understand the complexities of the world around us – until it doesn’t. Take the apparently simple organising principle of a species. You might have learned at school that a species is a group of individuals that can breed to produce fertile offspring. But this is just one of at least 34 competing definitions concocted over the past century by researchers working in different fields. Ecologists tend to categorise based on lifestyle. Palaeontologists focus on form. Geneticists sequence genomes and then create family trees based on shared, genetically encoded characteristics. The problem is that evolution – the origin of species – is intrinsically about gradual, random change (see “Think you understand how evolution works? You’re probably wrong”). Charles Darwin recognised that organisms live in populations that can diverge and evolve in different directions, especially if they face different environmental challenges. At some point, they become so distinct that we classify them as separate species. It just isn’t easy to pin down exactly when. We could just accept that “species” is a fluid, imperfect concept that helps us understand and conserve the diversity of the natural world. Unfortunately, it doesn’t always. This year, for example, genetic analysis of the world’s largest amphibian, the critically endangered Chinese giant salamander, revealed it was actually three species, not one, each requiring different conservation interventions. Traditional species concepts are further undermined by high levels of hybridisation in nature. One prominent example is the critically endangered red wolf found in the south-east US, which is now thought to be a cross between a coyote and a grey wolf.

12-11-19 Who do you think you are? Why your sense of self is an illusion
Most of us are convinced that we're coherent individuals who are continuous in time. There's just one problem with this sense of self – it can’t exist. LET’S be honest, it is what we think about the most: ourselves. What we want to eat or do, how we feel and whom we love. It is the essence of being. This selfhood generally feels like a continuous “me” sitting somewhere in our heads: a me that is the same today as yesterday. “Most people feel that they are a coherent, integrated individual. They have free will, they are making their choices and they’re looking out through their eyes at the world around them,” says Bruce Hood at the University of Bristol, UK, author of The Self Illusion. And that is just what selfhood seems to be – an illusion. “You are actually a collection of conflicting messages and signals and thought processes,” says Hood. “And these are somehow brought together to experience as unified self.” Fine, so your self is just the “you” experiencing that, right? That becomes a Russian doll problem, says Hood. “There’s someone inside the head who’s having these experiences taking place inside their head and so on,” he says. Neuroscience tells us that our subjective sense of self must be a distributed experience, involving various bits of the brain. Although experiments have taught us much about the brain areas involved in creating it, how exactly it is conjured up still eludes us. We do know that a sophisticated sense of self and others only comes on us gradually. “Understanding that your thoughts are different from someone else’s and being able to reflect on your own thinking, that’s a higher order skill and it doesn’t emerge until you are 3 or 4,” says Megan McClelland at Oregon State University. Even then, the brain areas involved in our experience of the self don’t fully mature until we become adults.

12-11-19 Ancient monkey painting suggests Bronze Age Greeks travelled widely
A Bronze Age painting on a Greek island shows a monkey from thousands of kilometres away in Asia. The finding suggests that ancient cultures separated by great distances were trading and exchanging ideas. The artwork is one of several wall paintings in a building at Akrotiri on the Greek island of Thera (Santorini) in the Aegean Sea. Akrotiri was a settlement of the Minoan civilisation in Bronze Age Greece that was buried by ash from a volcanic eruption in around 1600 BC. Many of the paintings show monkeys, yet there were no monkeys in Greece at the time. Most of the monkeys have been identified as Egyptian species like olive baboons. This makes sense because Egypt was in contact with the Minoan civilisation, which was spread across several Aegean islands. However, others were harder to identify. Marie Nicole Pareja at the University of Pennsylvania in Philadelphia teamed up with primatologists to re-examine the mystery monkey paintings. One stood out. “When they looked at this wall painting, they all straight away unambiguously said ‘that’s a langur’,” says Pareja. The team has identified the monkey as a grey langur (Semnopithecus). As well as its distinctive fur, the monkey was depicted holding its tail in a characteristic S shape. Grey langurs live in southern Asia in what is now Nepal, Bhutan and India – and particularly in the Indus Valley. During the Bronze Age, the region was home to the Indus Valley Civilisation, one of the most important societies of that time. Although it was past its peak, the Indus Valley Civilisation was still advanced for its time, with large cities and elaborate water supply systems.

12-11-19 44,000-year-old hunting scene is earliest painted ‘story’ ever found
Cave paintings discovered in Indonesia reveal ancient artists were conjuring imagined scenes 20,000 years earlier than we thought – but who painted them? A STUNNING cave painting discovered in Indonesia may be the earliest evidence of storytelling. The artwork is at least 43,900 years old, and shows that humans were depicting scenes tens of thousands of years earlier than previously thought. The painting is a 4.5-metre-wide hunting scene, discovered in the limestone cave of Leang Bulu’ Sipong 4 in Sulawesi in 2017 by Maxime Aubert of Griffith University, Australia, and his colleagues. Painted in a dark red pigment, it depicts at least eight small human-like figures hunting two pigs and four dwarf buffaloes with spears or ropes. “It’s a narrative scene,” says Aubert. He and his colleagues calculated the painting’s age by measuring the levels of uranium in calcite layers that cover the images (Nature, DOI: 10.1038/s41586-019-1806-y). At 43,900 years old, it could be the oldest figurative cave painting that has yet been found – although we don’t know what type of human made them. Until this discovery, the oldest known artworks depicting visual “stories”, with humans and animals interacting in a recognisable scene, dated from around 20,000 years ago and was found in Europe, such as the famous Lascaux paintings in France. “Now we show that at least 44,000 years ago, in South-East Asia, humans were telling stories and they were depicting them in rock art,” says Aubert. “It’s a really exciting discovery,” says Genevieve von Petzinger at the University of Victoria, Canada. “It shows an alternative timeline of how art developed. When you get a scene like this one, it opens the door a little further.”

12-11-19 Mystery illness that causes fever every few weeks finally identified
Seven people with a mysterious disorder that triggers a fever every few weeks have finally been given a diagnosis. A genetic analysis has revealed that all of them have a previously unknown disorder now called CRIA syndrome. The individuals, who were aged between 10 and 82 when they were first assessed, belong to three families in the US. All reported having had a fever every two to four weeks since they were babies, during which their body temperature can climb as high as 41°C. “You can imagine that having a fever and swollen lymph nodes every two weeks is not a good life,” says Najoua Lalaoui at Walter and Eliza Hall Institute of Medical Research in Australia. Some also experience other symptoms, including nausea, diarrhoea and mouth ulcers. To find out what might be causing these symptoms, Lalaoui and her colleagues looked at the individuals’ genes. Specifically, the team studied the exomes, the regions of DNA that code for proteins. The team found that all seven individuals have a mutation in a gene called RIPK1. The disorder caused by this mutation has never been described before, says Lalaoui. In another experiment, Lalaoui and her colleagues genetically engineered mice to carry the same mutation, which also had symptoms of the disorder. When these mice were given fragments of bacteria, their immune systems appeared to mount an exaggerated response, and the animals showed more signs of inflammation and cell death.The new finding may lead to more effective treatments for the seven affected individuals, as well as others given the same diagnosis. A separate research team in China has identified two further families with the same mutation and similar symptoms.

12-11-19 Arctic sea ice may vanish sooner than we thought – it happened before
Summer sea ice could vanish from the Arctic sooner than we thought. That is according to climate models that explain an unexpectedly warm period in Earth’s history. Our planet’s climate 6000 to 8000 years ago is a bit of a mystery. Some proxies – the things we use to gauge ancient temperature, such as pollen records – indicate global temperatures during the interval were perhaps 0.5°C higher than climate models suggest they should have been. This discrepancy is known as the “Holocene temperature conundrum”. However, a Korean-US team believes it may have the answer to the problem – and it lies in the Arctic. The researchers ran 13 climate models to investigate temperatures during thi 12-11-19

Think you understand how evolution works? You're probably wrong
A common misconception is that evolution naturally selects for biological complexity, eventually creating advanced organisms like us. That couldn't be further from the truth. FEW scientific concepts are as misunderstood as evolution. That isn’t just because of cultural resistance from religious fundamentalists. It has acquired all sorts of pseudoscientific baggage too, like the belief that it is about climbing a ladder of ever-increasing biological sophistication. Evolution can be that, but the reality is usually much less grandiose. “Evolution is changed gene frequencies in populations,” says evolutionary biologist Richard Dawkins. That is it. If, for some reason, a given gene in a patch of weeds, say, gets slightly more or less common from one generation to the next, evolution has happened. The gene doesn’t have to confer a survival advantage, or be “adaptive” or make the weed “fitter”. It doesn’t have to be “selected for” or increase biological complexity. It simply has to change in frequency, maybe by chance. That is all. After many generations, says Dawkins, we may notice this as a change in an organism’s phenotype: its observable characteristics and traits. But changes in gene frequency happen all the time, often randomly, with the appearance of a new mutation or the chance death of an individual. Under certain circumstances, a certain set of genes expressed in a certain environment can give that organism a slightly better-than-average chance of survival and reproduction. These genes are more likely to be passed on. Gene frequency has changed, and evolution has happened. But something else has taken place too: adaptation through natural selection. This special case of evolution renders a population fitter – as in a better fit, not physically fitter – for its environment.

12-11-19 Archaeologists have finally found ancient Egyptian wax head cones
The mysterious headgear appears often in art dating from around 3,550 to 2,000 years ago. Long before extraterrestrial Coneheads in Saturday Night Live skits claimed to have come from France, real-life cone heads existed in Egypt. Prominent people wearing cone-shaped headgear appear frequently in Egyptian art dating from around 3,550 to 2,000 years ago. But none of those cones have ever been found, until now. Archaeologists report unearthing two such headpieces at the ancient Egyptian city of Amarna. Built by the pharaoh Akhenaten and occupied from around 1347 B.C. to 1332 B.C., Amarna contains thousands of graves of ordinary people. Excavated skeletons of two people were topped by remnants of head cones, archaeologist Anna Stevens of Monash University in Melbourne, Australia, and colleagues report in the December Antiquity. One cone adorned the skeleton of a woman in her 20s. The other was atop the skeleton of a 15- to 20-year-old of undetermined sex. Scientists expected that graves of social elites would yield the first head cones, Stevens says. “But the most surprising thing is that these objects turned up at all.” Some scholars have argued that head cones existed only as artistic devices, not real objects. Portable infrared and X-ray machines determined that the cones were hollow and made of wax, probably beeswax. Although some investigators have speculated that head cones contained animal fat or wax scented with a substance such as tree resin, the Amarna finds contain no fat traces or perfume. Any perfume originally in the two head cones likely evaporated, Stevens says. Names and occupations of the cone-topped Amarna individuals, as well as the meanings attached to such headgear, are unknown. Stevens suspects that the head cones found at Amarna were believed to provide spiritual assistance in the afterlife.

12-10-19 Why is Earth so rich in oxygen? The answer is simpler than we thought
It may have been unexpectedly easy for the air to become rich in oxygen. A new simulation of the rise of oxygen suggests that it was driven by the planet itself, and needed little help from living organisms. The finding implies that planets with oxygen-rich atmospheres could be more common than we thought. “It’s easier, not just for our planet, but possibly for others as well,” says Lewis Alcott at the University of Leeds, UK, one of the authors of the work. For the first two billion years of Earth’s history, there was no oxygen in the air. That changed with the Great Oxidation Event around 2.4 billion years ago, when low levels of oxygen first appeared. This has often been attributed to the evolution of photosynthetic bacteria that release oxygen as a waste product. Oxygen levels then rose twice more: once between 800 and 540 million years ago, and again 450-400 million years ago. We have previously tried to explain the oxidation events by linking them to major evolutionary shifts or tectonic activity, says co-author Simon Poulton, also at the University of Leeds. For instance, the final rise has been linked to the spread of land plants. However, Alcott, Poulton and their colleague Benjamin Mills say there is no need to invoke any such dramatic events, other than the initial evolution of photosynthetic bacteria. They have shown that the behaviour of the planet is enough to explain the stepwise rises in oxygen levels. The key is that Earth’s mantle has been gradually cooling since the planet formed, and as it cools, it releases fewer volcanic gases such as carbon monoxide, which react with oxygen and remove it from the air. When the team modelled how this shift affected the cycling of oxygen around the planet, they observed three sharp increases in oxygen that corresponded to the known oxidation events.

12-10-19 The book that changed the way we talk about depression
Nowadays, it's not hard to find first-person narratives about depression. Podcasts about mental health are numerous. So, too, are stand-up comedy specials that deal frankly with mental illness, like recent stellar examples from Gary Gulman, Maria Bamford, Chris Gethard, and Neal Brennan. If you're a reader like me, you could spend years making your way through the canon of depression memoirs.. This was decidedly not the case in December of 1989, when one of the country's most celebrated novelists described his experiences with the illness in the pages of Vanity Fair. In a nearly 15,000-word essay, William Styron, the then-64-year-old author of The Confessions of Nat Turner and Sophie's Choice, took readers inside his mind during the throes of a recent depressive spell. It was a place, he said, of "dreadful, pouncing seizures of anxiety" and a "gray drizzle of horror," where "faith in deliverance, in ultimate restoration, [was] absent." A longtime drinker, Styron had tumbled into the abyss after developing a sudden intolerance for alcohol during the summer of 1985. Once the illness was upon him, he suffered intensely, to the point of contemplating suicide. He was admitted to a psychiatric ward of a Connecticut hospital, where he stayed for several weeks, and his anguish eventually lifted. He ended the account with a message of hope. "One need not sound the false or inspirational note to stress the truth that depression is not the soul's annihilation," he wrote. "Men and women who have recovered from the disease — and they are countless — bear witness to what is probably its only saving grace: it is conquerable." The Vanity Fair piece won a National Magazine Award, and a slightly expanded version was published as a bestselling paperback in 1990. In response, mail poured in to the magazine, and, later, to Styron personally. (According to his biographer, he kept these letters in a bureau in his work room.) Looking back, it's hard to overstate the cultural impact of the essay. The Atlantic's Peter Fulham has said, "Styron's book was, in almost every way, a first, and for that reason, his memory is solidified not just as a great American writer but as a pioneering advocate for mental health." Andrew Solomon, the author of The Noonday Demon: An Atlas of Depression, has said the book "liberated an enormous number of people to speak about their experience to themselves, to one another, to doctors who might be able to help them." Some medical schools began assigning Darkness Visible to students.

12-10-19 3D-printed bunny contains DNA instructions to make a copy of itself
A 3D-printed polyester rabbit has been embedded with DNA that contains a blueprint for printing additional bunnies. Using the information, researchers have replicated the rabbit several times, highlighting the potential for using DNA to store information in everyday objects. The plastic bunny was developed by the teams of Robert Grass at the Swiss Federal Institute of Technology in Zurich and Yaniv Erlich at Erlich Lab, a DNA storage company in Israel. “One day he [Erlich] wrote an email – ‘Hey, what if we put real information into your object? That would be really cool,’” says Grass. The four DNA bases –adenine (A), cytosine (C), thymine (T) and guanine (G) – were used to encode the 45 kilobyte instructions for making the bunny and the corresponding DNA sequence was then synthesised. The DNA was first packaged into microscopic spheres of glass to protect it, before being incorporated into the plastic that formed the bunny. The teams put their 3D-printed bunny to the test by cutting off a piece of plastic from its ear and isolating the embedded DNA. They used a DNA sequencing machine to read the specific sequence of DNA bases, which was then translated into instructions for the 3D printer. The 3D printer then produced a second, identical, plastic bunny, complete with DNA-containing glass spheres. The teams then used this second bunny to produce a third. They repeated this replication process four times in total. Replication was still possible after one of the bunnies had been stored for nine months. “We were extremely happy once we could read our first bunnies,” says Grass. He says his next goal is to make DNA storage an everyday technology. “The creativity of this embryonic field just keeps getting better,” says George Church at Harvard University. Church says the creation of a functional object with DNA memory is a “big step”. DNA storage could have future applications in manufacturing, where instructions could be stored locally in objects.

12-10-19 Lost Ethiopian town comes from an ancient empire that rivalled Rome
Archaeologists have uncovered an ancient buried town in Ethiopia that was inhabited for 1400 years. The town was part of a powerful civilisation called Aksum that dominated East Africa for centuries and traded with other great powers like the Roman Empire. “This is one of the most important ancient civilisations, but people [in the Western world] don’t know it,” says Michael Harrower of Johns Hopkins University in Baltimore, Maryland. “Outside of Egypt and Sudan, it’s the earliest complex society or major civilisation in Africa.” The Empire of Aksum dominated East Africa and parts of Arabia from about 80 BC to AD 825. It was one of the leading powers of the time, alongside Rome, Persia and China. Its capital, also called Aksum, still exists and has many tall, stone obelisks. Nobody knows how the Aksum civilisation developed. It was preceded by a “pre-Aksumite” society, the name of which is unknown. This earlier civilisation may have been based around Yeha in northern Ethiopia, which has the oldest writing and standing architecture in sub-Saharan Africa. For this reason, Harrower and his colleagues have surveyed the surrounding area.After discussions with local people, the team began excavating a hill near a village. The researchers found a grid of stone walls: the remains of buildings. “That’s what’s great about Ethiopia,” says Harrower. “In Greece and Rome, a lot of places have been explored and studied, so there’s not a lot of discoveries of major ancient towns any more.” The researchers called the town Beta Samati, which means “house of audience” in the local Tigrinya language. The find is “highly significant”, says Jacke Phillips at SOAS University of London. “Most of our known Aksumite and pre-Aksumite sites are old excavations, hastily conducted and badly published by today’s standards.”

12-6-19 Suspended animation in the ER
Doctors in Baltimore have placed humans in a state of suspended animation for the first time, as part of a groundbreaking trial that aims to give surgeons more time to save critically injured patients. Formally known as emergency preservation and resuscitation (EPR), the science fiction–like procedure is being tested on patients who arrive at the University of Maryland Medical Center with an acute trauma—such as a gunshot or stab wound—have lost more than half their blood, and have suffered a heart attack before reaching the operating table. Such patients typically have only a 5 percent chance of survival, and surgeons have just minutes to prevent death from oxygen and blood loss. With EPR, a patient’s blood is replaced with ice-cold saline, which rapidly cools the body temperature to about 50 degrees Fahrenheit and almost completely stops brain activity. This gives the doctors a two-hour window to perform surgery before they have to warm the body back up and restart the heart. The trial is ongoing, with results expected next year. Study leader Samuel Tisherman tells New Scientist it was “a little surreal” performing EPR for the first time, but says he is confident the procedure will “save lives.”

12-6-19 Ketamine vs. alcoholism
A one-off dose of ketamine could help heavy drinkers substantially cut back on their alcohol consumption, new research suggests.. The powerful sedative, sometimes known as the club drug Special K, has previously been shown to be highly effective in treating depression by helping patients rewrite their memories, reports NPR.org. To discover if ketamine could have a similar effect on alcoholism, a team at the University College London recruited 90 people who each drank the equivalent of 30 pints of beer a week. On the study’s first day, the participants were all shown pictures of alcoholic drinks, asked to rate their urge to drink, and then allowed to have a beer. The next day, the participants were divided into three groups: One group repeated the experiment but then received a dose of ketamine instead of beer. The second looked at the pictures and then took a placebo. The third was shown no pictures and received a ketamine shot. The results were impressive: Over a 10-day follow-up, the first group drank significantly less, and on fewer days, than the others. Nine months later, they had roughly halved their weekly alcohol consumption. (The other groups also reduced their intake but not by as much.) If the findings can be replicated, says John Krystal, head of psychiatry at Yale School of Medicine, “then it opens up a new window about a strategy to treat alcohol-use disorders.”

12-6-19 A once-scrapped Alzheimer’s drug may work after all, new analyses suggest
At the highest doses, aducanumab slowed mental decline, the drug developer claims. Call it a comeback — maybe. After being shelved earlier this year for lackluster preliminary results, a drug designed to slow Alzheimer’s progression is showing new signs of life. A more in-depth look at the data from two clinical trials suggests that patients on the biggest doses of the drug, called aducanumab, may indeed benefit, the company reported December 5. People who took the highest amounts of the drug declined about 30 percent less, as measured by a commonly used Alzheimer’s scale, than people who took a placebo, Samantha Haeberlein of the biotechnology company Biogen reported at the Clinical Trials on Alzheimer’s Disease meeting in San Diego. With these encouraging results in hand, Biogen, based in Cambridge, Mass., plans to seek drug approval from the U.S. Food and Drug Administration in early 2020. The results are “exhilarating, not just to the scientific community but our patients as well,” Sharon Cohen, a behavioral neurologist at the Toronto Memory Program, said during a panel discussion at the meeting. Cohen participated in the clinical trials and has received funding from Biogen. The presentation marks “an important moment for the Alzheimer’s field,” says Rebecca Edelmayer, director of scientific engagement for the Alzheimer’s Association in Chicago. Alzheimer’s disease slowly kills cells in the brain, gradually erasing people’s abilities to remember, navigate and think clearly. Current Alzheimer’s medicines can hold off symptoms temporarily, but don’t fight the underlying brain destruction. A treatment that could actually slow or even stop the damage would have a “huge impact for patients and their caregivers,” she says.

12-6-19 Samoan government takes drastic measures to fight measles outbreak
Red flags are flying in Samoa, indicating the houses of people in need of a measles vaccine. An outbreak on the Pacific island has led to drastic government measures to fight off the deadly disease. The Samoan Ministry of Health declared the start of the measles outbreak on 16 October and there have been more than 4300 cases reported since then, including 63 deaths linked to measles. Most of the deaths are among children under the age of 5. The government of Samoa declared an emergency on 19 November, closing schools and restricting children from attending public gatherings. The government also made vaccination mandatory for all 200,000 residents. In the first week after the emergency declaration, public health officials vaccinated 44,907 people, a quarter of the country’s population. As of 5 December, 74 per cent of the population had been vaccinated. The Samoan government undertook a door-to-door mass vaccination campaign on 5 and 6 December to vaccinate people between 6 months old and 60 years old. During that time, the government shut down services so that civil servants could help public health officials administer the vaccine in mobile clinics. Healthcare professionals from New Zealand and Hawaii flew in to help. According to estimates from UNICEF and the World Health Organization, the measles vaccination rate in Samoa fell from 74 per cent in 2017 to 34 per cent in 2018. That may be due in part to hesitancy among parents to vaccinate their children after two Samoan infants died in 2018 due to improperly prepared MMR vaccines. Measles is spreading throughout the region, with outbreaks in Tonga, Fiji, the Philippines and New Zealand.

12-6-19 Samoa arrests vaccination critic amid deadly measles crisis
Samoa has arrested an anti-vaccination campaigner as the country continues to battle a deadly measles outbreak. Edwin Tamasese was charged with incitement against a government order after he was detained on Thursday. The outbreak - which has killed at least 63 people, mostly young children, since October - is in part blamed on people spreading false information, claiming vaccinations are dangerous. Samoa declared a state of emergency, and made vaccinations compulsory. Measles is a highly contagious illness that causes coughing, rashes and fever. Although effective and safe vaccination is available, even some developed countries have seen a resurgence in recent years as unfounded fears about vaccine safety began to spread, often on social media. Samoa's low vaccination rates are in part due to the deaths in 2018 of two children wrongly being attributed to vaccination against measles, mumps and rubella. However, their deaths were due to nurses mixing the vaccine with a muscle relaxant instead of water, and not the vaccine itself. The cases had nonetheless raised local fears, and were exploited by people seeking false proof that vaccines are harmful. His words were echoed by Unicef representative to the Pacific Dr Sheldon Yett, who told the BBC earlier this month that "people who are spreading lies and misinformation about vaccinations are killing children". "The best way to keep children safe is to make sure they're immunised. Preventing vaccination and presenting false information kills children. That is clear - the evidence speaks for itself." Vaccination is not the only way Samoa is trying to end the outbreak. Earlier this week unvaccinated families were asked to hang a red flag outside their homes, while all schools have been closed and children under 17 are banned from public gatherings.

12-6-19 Will the world's 'first male birth control shot' work?
For a long time, there have been only two contraceptive solutions which rely directly on men. They can either wear a condom, or have sterilising surgery called a vasectomy to cut or seal the two tubes that carry sperm to the penis. A male birth control pill and a contraceptive gel are still in the works. But India says it is going to launch the world's first male birth control injection soon. Will this be the male contraceptive that succeeds? Invented by Sujoy Guha, a maverick 78-year-old Delhi-based biomedical engineer, the drug is a single preloaded syringe shot into the tubes carrying sperm from the testicle to the penis, under local anaesthesia. The non-hormonal, long-acting contraceptive, researchers claim, will be effective for 13 years. After years of human trials, the drug called Risug, an acronym for reversible inhibition of sperm under guidance, is ready. It is a viscous gel which inactivates the sperm. The effectiveness of a second part of the treatment - an injection which dissolves the gel, hopefully reversing the effects and allowing a man to father a child - hasn't yet been tested in humans, though it has worked in animal studies. And, like other non-barrier methods, the contraceptive injection wouldn't protect against sexually-transmitted infections. "This will be a world class contraceptive for men. It is safe and effective and lasts for long. We expect it will be cleared for production in the very near future," says RS Sharma, a reproductive biologist at the Delhi-based Indian Council of Medical Research and the drug's lead researcher. But there are some questions over whether this is truly a reversible contraceptive. Some scientists say Risug is really a replacement for surgical vasectomies, something which the Indian researchers do not entirely deny. "The contraceptive aspect of the drug still needs to be assessed with expanded reversibility studies. Presently it appears more like a sterilisation approach. The reversibility needed to allow the drug to become a contraceptive needs to be established," Michael Skinner, a reproductive biologist at Washington State University, told me.

12-6-19 Exclusive: First ever piglets containing monkey cells born in China
Pig-primate chimeras have been born live for the first time but died within a week. The two piglets, created by a team in China, looked normal but a small proportion of the cells in their body were derived from cynomolgus monkeys. “This is the first report of full-term pig-monkey chimeras,” says Tang Hai at the State Key Laboratory of Stem Cell and Reproductive Biology in Beijing. The ultimate aim of the work is to grow human organs in animals for transplantation. But the results show there is still a very long way to go to achieve this, the team say. Hai and his colleagues genetically modified cynomolgus monkey cells growing in culture to make them produce a fluorescent protein called GFP, enabling them to keep track of these cells and their descendents. They then derived embryonic stem cells from these modified cells and injected them into pig embryos five days after fertilisation. More than 4000 embryos were implanted in sows. Ten piglets were born as a result, of which two were chimeras. All died within a week of birth. In the chimeric piglets, multiple tissues including the heart, liver, spleen, lung, and skin partly consisted of monkey cells, but the proportion was low: between 1 in 1000 and 1 in 10,000. It is not clear why the piglets died, Hai says, but because the non-chimeric pigs died as well, the team suspects it is to do with the IVF process rather than the chimerism. IVF does not work nearly as well in pigs as it does in humans and some other animals. The team is now trying to create healthy animals with a higher proportion of monkey cells, Hai says. If that is successful, the next step would be to try to create pigs in which one organ is composed almost entirely of primate cells. Something like this has already been achieved in rodents. In 2010, Hiromitsu Nakauchi, now at Stanford University, created mice with rat pancreases, by genetically modifying the mice so their own cells couldn’t develop into a pancreas.

12-6-19 An ancient critter may shed light on when mammals’ middle ear evolved
How early the hammer, anvil and stirrup arose has been hard to pin down. Exceptionally preserved skulls of a mammal that lived alongside the dinosaurs may be offering scientists a glimpse into the evolution of the middle ear. The separation of the three tiny middle ear bones — known popularly as the hammer, anvil and stirrup — from the jaw is a defining characteristic of mammals. The evolutionary shift of those tiny bones, which started out as joints in ancient reptilian jaws and ultimately split from the jaw completely, gave mammals greater sensitivity to sound, particularly at higher frequencies (SN: 3/20/07). But finding well-preserved skulls from ancient mammals that can help reveal the timing of this separation is a challenge. Now, scientists have six specimens — four nearly complete skeletons and two fragmented specimens — of a newly described, shrew-sized critter dubbed Origolestes lii that lived about 123 million years ago. O. lii was part of the Jehol Biota, an ecosystem of ancient wetlands-dwellers that thrived between 133 million and 120 million years ago in what’s now northeastern China. The skulls on the nearly complete skeletons were so well-preserved that they were able to be examined in 3-D, say paleontologist Fangyuan Mao of the Chinese Academy of Sciences in Beijing and colleagues. That analysis suggests that O. lii’s middle ear bones were fully separated from its jaw, the team reports online December 5 in Science. Fossils from an older, extinct line of mammals have shown separated middle ear bones, but this newfound species would be the first of a more recent lineage to exhibit this evolutionary advance. O. lii apparently moved its jaw both in side-to-side and in rolling motions as it chewed. Such chewing ability, the team says, may have played a role in the evolutionary separation of the jaw and middle ear bones.

12-5-19 Cretaceous fossils are missing link in mammal ear evolution
Fossils of several shrew-like mammals that lived some 120 million years ago have revealed the earliest evidence of the middle ear bones separating from the jaw, a key step in the evolution of hearing. Three tiny bones in the middle ear, known as the incus, malleus and stapes (or hammer, anvil and stirrup), are responsible for the exceptional hearing found in mammals such as dolphins and bats. Biologists think that this complex architecture gradually evolved as the bones behind the back teeth of the lower jaw shrank and were pushed back. But fossil evidence of how and when this transition happened is rare. Now Jin Meng at the American Museum of Natural History and his colleagues have discovered proof of this missing link in several nearly complete skeletons of a previously unknown creature, Origolestes lii, found in the Yixian Formation in Liaoning province, China. The middle ear bones in this mole-sized creature sit behind and at the base of its jawbone, but like in modern mammals, are completely separate from the jaw. In particular, O. lii’s middle ear bones weren’t connected to the jaw through a bridge called Meckel’s cartilage – a feature found in a relative that lived around the same time. evolutionary time”. The evolution of small and loose bones allowed mammals to hear at higher frequencies, and this may have helped them catch insects, says Meng. “On the other hand, the selection pressure for eating different food, such as vegetables and meat, require strong jaw movement, which would be constrained if the hearing organ was attached to the lower jaw,” he says. Once the two were separate, hearing and chewing were both able to evolve rapidly without each impairing the other.

12-5-19 African swine fever helps drive world food prices to two-year high
The slaughter of half of China’s pigs due to a virus raging across Asia and Europe has helped drive world food prices to a two-year high. The United Nations said today that global food prices rose significantly in November, up nearly 10 per cent on the same month last year, pushed up by a combination of rising meat and vegetable oil prices. Meat prices jumped by 4.6 per cent on the UN Food and Agriculture Organization’s meat price index, the biggest month-on-month rise for more than a decade. One reason is China importing meat other than pigs to fill the gap left by the domestically-produced pigs killed due to African swine fever. World food prices rose the most for cattle and mutton, the FAO said, buoyed by strong demand for imports, particularly from China as end-of-year festivities approach. “African swine fever is obviously a huge reality in the world. It has pushed up the meat index over the course of the year. And it has led to China importing a lot of other meat, also pushing up prices,” says a spokesperson for the FAO. Meat imports to China do have some impact on world food prices – pig meat imports are up 49 per cent and bovine imports 54 per cent between January and October – but the effect is limited because Chinese imports are dwarfed by its domestic production. Some of the gap left by Chinese pigs culled to stop the spread of the virus or killed by it directly has been filled by ramped-up domestic poultry production. While cereal production is set to hit a record high this year – up 2.1 per cent on 2018 to 2714 million tonnes – vegetable oils bumped up global food prices last month. The FAO’s vegetable food oils index was up 10.4 per cent in November, driven in part by Indonesia requiring more biodiesel be blended in with petrol supplies, in turn diverting more palm oil from food to energy.

12-5-19 A gene tied to facial development hints humans domesticated themselves
Called BAZ1B, it may also help explain why domesticated animals look cuter than their wild kin. Domestic animals’ cuteness and humans’ relatively flat faces may be the work of a gene that controls some important developmental cells, a study of lab-grown human cells suggests. Some scientists are touting the finding as the first real genetic evidence for two theories about domestication. One of those ideas is that humans domesticated themselves over many generations, by weeding out hotheads in favor of the friendly and cooperative (SN: 7/6/17). As people supposedly selected among themselves for tameness traits, other genetic changes occurred that resulted in humans, like other domesticated animals, having a different appearance than their predecessors. Human faces are smaller, flatter and have less prominent brow ridges than Neandertal faces did, for instance. Domesticated animals look different from their wild counterparts as well. Shorter snouts, curly tails, floppy ears and spotted coats are all traits that tend to pop up in domesticated animals. But until recently, no one had an explanation for this “domestication syndrome.” Then in 2014, three scientists proposed that as people selected animals for tameness, they also happened to select for genetic changes that slightly hamper movement of some developmentally important cells (SN: 7/14/14). These neural crest cells are present early in embryonic development and migrate to different parts of the embryo where they give rise to many tissues, including bones and cartilage in the face, smooth muscles, adrenal glands, pigment cells and parts of the nervous system. The researchers’ idea was that mild genetic changes might produce neural crest cells that don’t move as well, leading to domestic animals’ cuddlier look.

12-5-19 Scientists’ brains shrank a bit after an extended stay in Antarctica
The effects of isolation and a monotonous environment may be to blame. Socially isolated and faced with a persistently white polar landscape, a long-term crew of an Antarctic research station saw a portion of their brains shrink during their stay, a small study finds. “It’s very exciting to see the white desert at the beginning,” says physiologist Alexander Stahn, who began the research while at Charité-Universitätsmedizin Berlin. “But then it’s always the same.” The crew of eight scientists and researchers and a cook lived and worked at the German research station Neumayer III for 14 months. Although joined by other scientists during the summer, the crew alone endured the long darkness of the polar winter, when temperatures can plummet as low as –50° Celsius and evacuation is impossible. That social isolation and monotonous environment is the closest thing on Earth to what a space explorer on a long mission may experience, says Stahn, who is interested in researching what effect such travel would have on the brain. Animal studies have revealed that similar conditions can harm the hippocampus, a brain area crucial for memory and navigation (SN: 11/6/18). For example, rats are better at learning when the animals are housed with companions or in an enriched environment than when alone or in a bare cage, Stahn says. But whether this is true for a person’s brain is unknown. Stahn, now at the Perelman School of Medicine at the University of Pennsylvania, and his colleagues used magnetic resonance imaging to capture views of the team members’ brains before their polar stay and after their return. On average, an area of the hippocampus in the crew’s brains shrank by 7 percent over the course of the expedition, compared with healthy people matched for age and gender who didn’t stay at the station, the researchers report online December 4 in the New England Journal of Medicine.

12-4-19 We constantly eat microplastics. What does that mean for our health?
Tiny particles of plastic are in our food, water and even the air we breathe. We investigate the impact they have inside our bodies. THIS morning I tried to count how many plastic objects are in my house. I got as far as the bottom drawer in my kitchen cabinet – which contained 147 assorted plastic boxes, lids, cups, straws and disposable cutlery – then gave up. I had to get to work. Good job I didn’t get down on my hands and knees with a microscope to look for really small bits of plastic, because I would never have left. By some estimates, the average household generates 6 kilograms of plastic dust every year, around 700 billion fragments known as microplastics. Like snowflakes, every one is different. Every one may also be harmful. They aren’t just indoors. “They are everywhere,” says Dick Vethaak, an environmental toxicologist at the Deltares research institute in Delft, the Netherlands. “In the water, in food, in the air – you are surrounded by a cloud of them. Everything is contaminated.” More are created every day and they will be with us for centuries. Big plastic debris has been on our radar for years. Yet this is just the start of something more insidious. Plastic waste doesn’t biodegrade but it does break down, fragmented by wind, waves and sunlight into ever-smaller pieces. They may be too small to see, but they are still there, worming their way into every nook and cranny of the environment – including our bodies. This, in a nutshell, is the pervasive problem of microplastics. But beyond knowing that they exist and are everywhere, we are woefully ignorant about them and their potential impact on us. That is why the search for answers is taking on a new urgency. It is widely assumed that microplastics are harmful to the environment and ongoing research suggests that this is a fair assumption. But when it comes to human health, we are flying almost blind. “It is only just very recently that we recognised that we are dealing here with a health issue,” says Vethaak.

12-4-19 Monthly oral contraceptive capsule shown to work in pigs
An oral contraceptive capsule may only need to be taken once a month. In tests in pigs, the capsule slowly released a contraceptive into the stomach that then persisted in the blood for weeks. “This is the first example that I’m aware of a capsule that can deliver a drug over the course of a month,” says Giovanni Traverso at the Massachusetts Institute of Technology, part of the team that developed the capsule. The team designed the capsule’s drug delivery system so that it would stick around in the stomach. Within the capsule is a structure made up of six arms attached to a central body. Each arm is loaded with the progestogen contraceptive levonorgestrel. While inside the capsule the structure is folded up, but once the capsule reaches the stomach it starts to degrade. This releases the structure, allowing the arms to unfold and create a star that opens to such a size that it cannot fit through the sphincter that controls the exit of the stomach. Over the next few weeks, the hormone is gradually released, before the arms eventually fall off and the pieces pass through the body, says Traverso. So far, Traverso and his colleagues have only tested their contraceptive in pigs. Three animals given the capsule had similar blood levels of the contraceptive to five female pigs that were given the daily version of the oral contraceptive, although these levels did drop over the course of a month. The researchers plan to incorporate oestrogen along with progestogen before they trial the capsule in people as this is the more common format for long-acting contraceptives, says Traverso. He hopes to start human trials within the next five years. He imagines the once-a-month contraceptive being especially useful in low-to-middle income countries.

12-4-19 A single gene controls how our faces develop when we are young
A single gene controls much of the development of the human face. The same gene is also involved in the domestication of dogs – suggesting that we have domesticated ourselves as a species. The finding is one of the first pieces of hard evidence for the idea that humans are self-domesticated. Over generations, humans have evolved less aggressive behaviours and appearances, says Giuseppe Testa at the European Institute of Oncology in Milan, Italy. This paved the way for large-scale societies in which thousands or millions of people cooperate. Domestic animals are recognisably different from their wild cousins. For example, dogs’ faces are relatively short compared with wolves, and they often have small teeth and floppy ears. Domestic animals also tend to be more sociable towards humans. Human faces look similarly “domesticated” compared with other hominin species, such as Neanderthals. Our faces are flatter and don’t have prominent brow ridges – and we are unusually social and cooperative. As a result, some scientists suspect that before we domesticated dogs and cattle, we first domesticated ourselves. All the parts of the body that are affected by domestication are derived from a single cluster of cells in the developing embryo called the neural crest. This implies that changes to the neural crest might underlie domestication. By studying the genes that control the neural crest, some biologists hope to show that the same kinds of genetic changes are behind the domestication of dogs and humans. Testa’s team studied a gene called BAZ1B, which is known to be involved in controlling the neural crest. BAZ1B is crucial for the development of the face. It belongs to a cluster of genes on chromosome 7, mutations in which cause Williams syndrome, a genetic disorder that causes distinctive facial characteristics and hyper-sociability. The dog version of the gene has been linked to domestication.

12-4-19 Samoa measles: Unvaccinated families told to hang red flag on door
Families that have not been vaccinated against measles in the Pacific nation of Samoa have been asked to hang a red flag outside their homes to help fight a deadly outbreak of the disease. The flags will assist medical teams travelling door to door inoculating residents. The government says more than 4,000 people have been infected with measles out of a population of 200,000. Sixty people have died so far, many of whom were children under five. Samoa declared a state of emergency in November to combat the outbreak and vaccinations are now compulsory. All schools are closed and children under 17 are banned from public gatherings. Samoan officials say the vaccination rate has now reached about 55%. Prime Minister Tuilaepa Sailele Malielegaoi has vowed to get the figure above 90%. "Our children and people will never become immune to any future epidemic unless we have almost 100% vaccination coverage," he said while touring a hospital ward on Wednesday. "It's the only antidote." Unicef has sent 110,500 vaccines to the country, and New Zealand has sent medicine, nurses and equipment - while battling an outbreak of the disease itself. It usually takes between 10 days and two weeks for a vaccine to start working. Some people are reportedly peddling false treatments. One businessman told Australian broadcaster ABC that his "Kangen Water" - in reality, tap water - could alleviate symptoms. Tonga and Fiji have also declared states of emergency to tackle their measles outbreaks in the last month. However, both countries have far higher vaccination rates - more than 90% in both countries - and have so far not reported any deaths. The Tonga women's rugby team were put in quarantine on Thursday after a measles outbreak. Measles is a highly infectious viral illness that can sometimes lead to serious health complications, including infections of the lungs and brain. (Webmaster's comment: All unvaccinated people; men, women and children, should be forced to wear a red patch on their clothes that says "I am unvaccinated and a serious danger to your health!")

12-3-19 Cholesterol levels predict if under-45s will ever have heart disease
A person’s cholesterol levels before the age of 45 can predict their lifetime risk of developing cardiovascular disease. The finding has prompted debate about whether younger people should be recommended preventative measures, such as taking statins. The result comes from an analysis of medical data on nearly 400,000 people of European ancestry from across Europe, Australia and North America. The study found that when blood concentrations of non-HDL cholesterol – often known as “bad cholesterol” – are higher than 145 milligrams per 100 millilitres before the age 45, a person’s relative risk of developing heart disease at some point in their life nearly doubles. For concentrations between 100 and 145 milligrams before 45, the relative lifetime risk increases by 10 to 20 per cent. “It is important because people might want to know how they could lower their risk,” says Frank Kee at Queen’s University Belfast, UK, who worked on the study. We have known since the 1980s that cholesterol is linked to atherosclerosis – the clogging of arteries that can cause cardiovascular disease, which includes heart disease and stroke. There are many ways a person can lower their lifetime risk of this, such as lifestyle changes and taking medications. For example, in the past 30 years, statin drugs have been widely prescribed to lower cholesterol, contributing to small life expectancy gains. Under existing guidelines, people in the UK and US are only prescribed statins based on their estimated 10-year risk of developing cardiovascular disease, not their lifetime risk, says Kee. The study provides compelling data that lowering cholesterol earlier on in life could be highly beneficial, says Betty Raman at the University of Oxford.

12-3-19 Artificial neurons developed to fight disease
Scientists have made artificial nerve cells, paving the way for new ways to repair the human body. The tiny "brain chips" behave like the real thing and could one day be used to treat diseases such as Alzheimer's. A team from the University of Bath used a combination of maths, computation and chip design to come up with a way to replicate in circuit form what nerve cells (neurons) do naturally. Neurons carry signals to and from the brain and the rest of the body. Scientists are interested in replicating them, because of the potential that offers in treating diseases such as Alzheimer's, where neurons degenerate or die. Prof Alain Nogaret, from Bath's department of physics, said the novelty of their research was to transfer the electrical properties of brain cells on to synthetic circuits made from silicon. "Until now, neurons have been like black boxes, but we have managed to open the black box and peer inside," he said. "Our work is paradigm-changing because it provides a robust method to reproduce the electrical properties of real neurons in minute detail." Making artificial neurons that respond to electrical signals from the nervous system has been a long-time goal in medicine. Challenges included designing the circuits and finding the parameters that make the circuits behave like real neurons. "We have managed to extract these parameters for biological neurons and plug these parameters into the synthetic circuits we have made," said Prof Nogaret. The researchers replicated two types of neurones, including cells from the hippocampus, an area of the brain that plays a major role in memory, and brain cells involved in the control of breathing. The work opens up a range of possibilities in repairing the neuron that have been lost to degenerative disease, including medical implants to treat conditions such as heart failure and Alzheimer's.

12-3-19 Revealed: Mental health websites are selling your data to advertisers
Mental health websites are sharing user data with advertisers, including the results of tests for depression. This means that people seeking information or help for mental health conditions can be targeted with adverts while they may be vulnerable. Eliot Bendinelli at Privacy International in London and his colleagues looked at 136 of the most popular websites in the UK, France and Germany that provide resources and information about mental health conditions. The researchers found that 76 per cent of the websites contained third-party marketing trackers. These collect information about a user and can track them as they browse other sites. This can be combined into a detailed profile. Many of the pages had trackers from Google, Facebook and Amazon and shared information with data brokers – firms that aggregate information and sell individual profiles to other organisations – and advertising companies. “It’s currently almost impossible to seek information and help about depression without advertisers knowing,” says Frederike Kaltheuner at the Mozilla Foundation in London, who is part of the team. “Knowing who is depressed and when allows advertisers to target people when they are at their most vulnerable. Feeling low today? Here are some diet pills.” Advertisers target users based on their personal data, such as their IP address and location, and the site they visit, says Bendinelli. Some sites also have real-time bidding, where information, including a page’s content and URL, is used to instantaneously show a relevant ad on the page. Several websites with questionnaires about depression stored users’ answers and shared them with third parties. When the researchers first analysed the UK’s National Health Service website in September, they found that a mood self-assessment quiz shared individual answers, test scores and the test URL with Adobe for analysis purposes. However, the NHS website has since updated its privacy policy so users now need to manually opt in to be tracked.

12-3-19 Medications alone work as well as surgery for some heart disease patients
Patients with stable ischemic heart disease can avoid stents or bypass surgery. In their heyday, stents and bypass surgery were the go-to treatment for patients newly diagnosed with heart disease. That began to change about a decade ago, after new data emerged suggesting these procedures were no better than treatment with medical therapy alone for patients whose heart-related symptoms aren’t considered an emergency. Now a large study has tipped the scales further, reporting that statins, aspirin and other medications together protect these patients just as well as stents or bypass surgery against heart attacks and death. The key to managing these patients, who have stable ischemic heart disease, “is medicines, medicines, medicines,” says Michael Gavin, a cardiologist at Beth Israel Deaconess Medical Center in Boston who was not involved in the study. “That’s what’s going to stop you from having a heart attack.” Going the medical therapy route does require that patients are committed to that route. That means seeing the doctor regularly, keeping up with medications and exercise and eating a healthy diet. Medical therapy “gives a good prognosis,” says preventive cardiologist Gina Lundberg of Emory University School of Medicine, who was not involved in the study. But “you can’t say ‘I don’t want the stent,’ and then not do all those things, and get a good result.” The federally-funded study, called ISCHEMIA, is the largest clinical trial to examine whether medical therapy alone, or along with stents or bypass surgery, reduces death or heart attacks in patients who have heart disease primarily due to plaque-containing, narrowed coronary arteries, but who have manageable pain or other symptoms. The participants in the invasive procedure group had a device threaded through the arteries, followed by placement of a stent to keep an artery open or else bypass surgery to divert blood flow around a blockage. The procedures come with risks such as bleeding or the formation of blood clots that can block an artery again.

12-3-19 An ancient outbreak of bubonic plague may have been exaggerated
Archaeological evidence suggests a sixth century epidemic didn’t radically change European history. An ancient bubonic plague outbreak often characterized as a mass killer that felled Eurasian civilizations was actually pretty tame, researchers say. Known as the Justinianic plague, the outbreak likely didn’t cause enough deaths to trigger major events such as the eastern Roman Empire’s decline, Islam’s rise and the emergence of modern Europe, say environmental historian Lee Mordechai and his colleagues. Many scholars have argued that the Justinianic plague caused tens of millions of deaths starting in the sixth century and reduced European and Middle Eastern populations by 25 to 60 percent. Economies crumbled as a result, devastating what was left of the Roman Empire and ushering in a period of cultural stagnation, from this perspective. But several new lines of archaeological evidence related to ancient population and economic changes challenge that scenario, Mordechai and his team report December 2 in the Proceedings of the National Academy of Sciences. “Support for the claim that the Justinianic plague was a watershed event in the ancient world is just not there,” says study coauthor Merle Eisenberg, an environmental historian at the University of Maryland’s National Socio-Environmental Synthesis Center in Annapolis. Yet a scenario of the plague outbreak wiping out populations and reshaping societies appears in many textbooks on ancient history, he says. The Justinianic outbreak, caused by the plague bacterium Yersinia pestis, occurred several centuries before the more widely known Black Death plague, which killed tens of millions of people in the 14th century (SN: 1/17/16). An initial outbreak began during the reign of Emperor Justinian, who ruled the eastern part of the Roman Empire after the fall of Rome, and ran from around 541 to 544. Intermittent plague reoccurrences lasted until around 750, and stretched around the Mediterranean and into Europe and the Middle East.

12-2-19 Two brain networks behave differently in people who are suicidal
People who are suicidal seem to have unusual patterns of brain activity. The differences aren’t big enough to identify people who may try to kill themselves. “But we hope it will provide us with more information about what may be happening in terms of brain mechanisms,” says Anne-Laura van Harmelen at the University of Cambridge. The finding comes from a review of 131 brain-scan studies, comprising more than 12,000 people. The analysis looked to see if there are distinctive patterns of brain activity in those who had made suicide attempts or had been thinking about suicide. Most of these studies compared people with a certain mental health condition, such as depression, who had a history of suicidal behaviour, to a similar group with that condition who hadn’t become suicidal, or to people without mental health problems. Van Harmelen and her colleagues found that two brain networks appear to function differently. One of these involves areas at the front of the head known as the medial and lateral ventral prefrontal cortex and their connections to regions involved in emotion. This may lead to difficulties regulating emotions, says van Harmelen. A second involves regions known as the dorsal prefrontal cortex and inferior frontal gyrus system, which play a role in decision making. However, the differences in these brain networks may just reflect that people who are suicidal are in more distress, rather than indicating specific thoughts of suicide. Other groups are trying to develop a blood test to predict suicidal behaviour – but this hasn’t yet been turned into something that can be used in the clinic. At the moment psychiatrists tend to use screening questionnaires to find those at most risk, but these aren’t very accurate.

12-2-19 Infrared images reveal hidden tattoos on Egyptian mummies
The images of eyes, crosses and more on 7 females may challenge ideas about the practice. Modern technology is illuminating tattoos on mummified, ancient Egyptians that until now had gone unnoticed. Infrared photography has helped to identify tattoos on seven mummified individuals dating to at least 3,000 years ago at a site called Deir el-Medina, archaeologist Anne Austin of the University of Missouri–St. Louis reported November 22 at the annual meeting of the American Schools of Oriental Research. Although the identities of these tattooed folks are unknown, artisans and craft workers at Deir el-Medina built and decorated royal tombs in the nearby Valley of the Kings and Valley of the Queens. Until the Deir el-Medina discoveries, tattoos had been found on a total of only six mummified individuals over more than a century of research at ancient Egyptian sites. But infrared photos, which display wavelengths of light invisible to the naked eye, are transforming what’s known about tattooing in ancient Egypt, Austin said. “It’s quite magical to be working in an ancient tomb and suddenly see tattoos on a mummified person using infrared photography,” said Austin, who, along with her colleagues, examined the mummies in 2016 and 2019. That research was conducted while Austin was working with the French Institute of Oriental Archaeology in Cairo. Designs and placement of tattoos vary greatly on the 13 Egyptian mummies, which consist of 12 women and one man. A female mummy found in 1891 bore the first known tattoo from ancient Egypt. More recently, archaeologist Renée Friedman of the University of Oxford in England used infrared imaging to reveal tattoos on one male and one female Egyptian mummy housed at the British Museum in London (SN: 3/9/18). Those people lived in Egypt shortly before the rise of the first pharaoh around 5,100 years ago.

12-1-19 Is taking birth control as a teen linked to depression? It’s complicated
It’s hard to study hormones and the teen brain. “Does the pill cause depression?” the news headline asked. Prompted by a recent study that described a link between taking birth control pills as a teenager and depression in adulthood, the news got some doctors hopping mad. Early research hints that there are reasons to look more closely at hormonal birth control’s side effects. But so far, the link is less than certain. “This is a premature connection,” says pediatrician Cora Breuner of Seattle Children’s Hospital. Putting too much stock in preliminary evidence may lead to fewer teenagers getting birth control and, in turn, more unwanted pregnancies among teens — a situation that can upend young lives, Breuner says. Headlines that frighten teens, their families and doctors are “yet another barrier in place for accessing a completely effective way to prevent unplanned pregnancies.” Ob-gyn and contraception researcher Katharine O’Connell White agrees. “Birth control gets all of the worry and concern,” says White, of Boston University School of Medicine. “But we know that other things are much more dangerous.” Teen pregnancy, for instance. Access to effective birth control is vital for sexually active teenagers, the doctors say. “I don’t think the evidence is there right now to say that this is a threat,” adds epidemiologist and public health researcher Sarah McKetta of Columbia University, who has studied birth control use in teens. Still, she sees value in more research on the issue. “Women deserve good medication … that’s not giving them problems.” If there are risks that come with the pill, then scientists ought to get a handle on them. More than half of U.S. teens, boys and girls, have had sexual intercourse by their last year in high school, a situation that highlights the need for access to reliable birth control.

12-1-19 How advancements in DNA technology can help save the tigers
The technology is still in its infancy, but scientists are optimistic it can help in the fight to protect the endangered animal. iger DNA expert Uma Ramakrishnan gets special permission to wander India's protected forests on foot, following the same trails the big cats tread. While she enjoys coming across tigers and their cubs and watching them with binoculars, those sightings aren't the treasure she's after. What she loves most is to find tiger droppings — "almost like gold to me," says the molecular ecologist at the National Centre for Biological Sciences in Bangalore. Territorial tigers oblige by leaving scat regularly, as a warning to other tigers that this space is occupied. These nuggets contain genetic material that scientists like Ramakrishnan use to understand tiger populations: How many are there, and what kinds? Where did they come from, and how far do they travel? It's crucial information for conservation efforts. Tigers are endangered, with fewer than 4,000 wild ones roaming the lands of at least 10 nations, from Eastern Russia to the island of Sumatra. That's down from an estimate of 100,000 in 1900. Human activity such as urban development, logging, farming, and mining has fragmented and destroyed tigers' forest habitats, and poaching is an ongoing problem in parts of Southeast Asia. "If you're going to have conservation management, you have to know what you're dealing with," says Stephen O'Brien, a geneticist at St. Petersburg State University in Russia and Nova Southeastern University in Fort Lauderdale, Florida. For example, genetic studies show that tigers are split into several subspecies, so conservationists may want to develop strategies to protect each group. Over the past two decades, scientists have built up a picture of tiger evolution and ecology based on their DNA, as described this year in the Annual Review of Animal Biosciences. Early on, scientists could only look at a handful of spots in the tiger genome. Today, with the advent of inexpensive DNA sequencing and genomics that covers every bit of the instructions to make a tiger, experts are gaining a much broader picture of tiger biodiversity. DNA analysis — which will help not just to save tigers, but also to preserve the range of genetic variety that they carry — "is one of the best tools we have," says Byron Weckworth, conservation genetics director for Panthera, the global wild cat conservation organization in Missoula, Montana. That said, he adds, the application of genomic information to conservation is still in its infancy.


96 Evolution News Articles
for December 2019

Evolution News Articles for November 2019