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      Ancient Maya Genomes Sequenced for First Time

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      Thousand-year-old DNA from Chichén Itzá offers eye-opening details of the religious rituals of ancient Maya.In the spring of 1967, workers building a small airport behind Chichén Itzá, the ancient Maya city in Mexico, ran into a problem: Their excavations had uncovered human remains in the pathway of the proposed runway. The airport was set to serve V.I.P.s who wanted to visit Chichén Itzá. But with the remains so close to a major archaeological site, the work had to be halted until the bones could be examined.Any hope for a quick resolution dissolved when archaeologists who were called to the scene uncovered a chultún — an underground rainwater-storage container that, in Maya mythology, was viewed as an entrance to the subterranean land of the dead. Connected to the cistern was a cave containing more than 100 sets of human remains, almost all belonging to children. In a push to finish the airport, researchers were given just two months to excavate and exhume the cache of bones.Nearly 60 years later, ancient DNA extracted from 64 of the children is offering new insights into the religious rituals of the ancient Maya and their ties to modern descendants. In a paper published on Wednesday in the journal Nature, an international cohort of researchers revealed that the children — sacrificial victims killed between 500 and 900 A.D. — were all local Maya boys that may have been specifically selected to be killed in sibling pairs.“These are the first ancient Maya genomes to be published,” said Johannes Krause, an archaeogeneticist at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. The DNA work provided a previously unseen glimpse into the identities of the sacrificed children. “One feels quite moved by such a finding,” Dr. Krause said, noting that he himself has a young son.The search into the genome of the Maya boys did not start as an exercise in ancient Maya rituals. In the mid-2000s, Rodrigo Barquera — now an immunogeneticist at the Max Planck Institute — was hoping to discover the genetic legacy of Mesoamerica’s deadliest pandemic.In 1545, an outbreak of Salmonella enterica spread like wildfire across what is now Mexico. Over the next century, the disease killed up to 90 percent of the Indigenous population. Pandemics like these often leave their mark on the immune genes of survivors. To uncover this genetic legacy, Dr. Barquera and his colleagues needed to compare the DNA from the precolonial remains with that of people who were born after the calamity.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe. More

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      Abortion Pills May Become Controlled Substances in Louisiana

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      A bill that is expected to pass would impose prison time and thousands of dollars in fines on people possessing the pills without a prescription.Louisiana could become the first state to classify abortion pills as dangerous controlled substances, making possession of the pills without a prescription a crime subject to jail time and fines.A bill that would designate the abortion pills mifepristone and misoprostol as Schedule IV drugs — a category of medicines with the potential for abuse or dependence — passed the state’s Republican-controlled House of Representatives on Tuesday by a vote of 63 to 29. Should the Senate follow suit, Gov. Jeff Landry, a Republican and a vocal opponent of abortion, is likely to sign the legislation into law.The measure — which would put abortion pills in the same category as Xanax, Ambien and Valium — contradicts the way the federal government classifies mifepristone and misoprostol. The federal Food and Drug Administration does not consider abortion pills to be drugs with the potential for dependence or abuse, and decades of medical studies have found both to be overwhelmingly safe.Under the legislation, possession of mifepristone or misoprostol without a prescription in Louisiana could be punishable with thousands of dollars in fines and up to five years in jail. Pregnant women would be exempt from those penalties; most abortion bans and restrictions do not punish pregnant women because most voters oppose doing so.“These drugs are increasingly being shipped from outside our state and country to women and girls in our state,” Attorney General Liz Murrill, a Republican, said in a statement on social media. “This legislation does NOT prohibit these drugs from being prescribed and dispensed in Louisiana for legal and legitimate reasons.”Louisiana already bans most abortions, except when women’s lives or health are in danger or fetuses have some fatal conditions. As a result, abortion rights advocates and legal scholars said that in practice, the measure might not prevent many abortions among Louisiana women. Since the state imposed its strict abortion ban after the Supreme Court overturned Roe v. Wade, many patients have traveled to states where abortion is legal or have obtained pills under shield laws from doctors or nurses in other states who prescribe and mail the medications to Louisiana. Such circumstances would not be affected by the new bill, experts say.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe. More

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      The Disease Detectives Trying to Keep the World Safe From Bird Flu

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      As Dr. Sreyleak Luch drove to work the morning of Feb. 8, through busy sunbaked streets in Cambodia’s Mekong river delta, she played the overnight voice messages from her team. The condition of a 9-year-old boy she had been caring for had deteriorated sharply, and he had been intubated, one doctor reported. What, she wondered, could make the child so sick, so fast?“And then I just thought: H5N1,” she recalled. “It could be bird flu.”When she arrived at the airy yellow children’s ward at the provincial hospital in Kratie, she immediately asked the child’s father if the family had had contact with any sick or dead poultry. He admitted that their rooster had been found dead a few days before and that the family had eaten it.Dr. Luch told her colleagues her theory. Their responses ranged from dubious to incredulous: A human case of avian influenza had never been reported in their part of eastern Cambodia. They warned her that if she set off the bird flu warning system, many senior government officials might get involved. She risked looking foolish, or worse.Anxious but increasingly certain, Dr. Luch phoned the local public health department, located just across the street. Within minutes, a team arrived to collect a sample from the child, Virun Roeurn, for testing in a lab.By then, Virun’s distraught parents had lost faith in the hospital. They demanded that he be sent by ambulance to the capital, Phnom Penh. His flu swab sample traveled with him.Virun died on the journey. At 8 p.m., Cambodia’s National Public Health Laboratory confirmed Dr. Luch’s suspicion: He had died of highly pathogenic avian influenza.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe. More

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      Legalized Weed is Landing More Seniors in the E.R.

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      In Canada, cannabis poisonings rose sharply among people 65 and older after the country legalized the drug, a new study found.The NewsAs more places legalize marijuana, policymakers and health officials have worried about the health risks that the drug may pose to adolescents. But a new study suggests that an additional demographic is at risk: seniors.The study, published Monday in JAMA Internal Medicine, found that after Canada legalized marijuana, the number of emergency room visits for cannabis poisoning rose sharply among people ages 65 and older. Poisonings doubled after Canada legalized sale of the cannabis flower, and then tripled just 15 months later, when Canada legalized the sale of edibles.“It’s often a baked good, a chocolate or a gummy,” said Dr. Nathan Stall, a geriatrician at Mount Sinai Hospital and researcher at Women’s College Hospital in Toronto, and lead author on the study. Dr. Stall noted that researchers and emergency room doctors were finding that seniors used drugs intentionally but also sometimes by accident, when edibles were mistaken for regular food or snacks.Symptoms of cannabis poisoning can include dizziness, confusion, nausea, loss of coordination and balance, drowsiness and hallucinations.The findings were consistent with other research published in the United States, Dr. Stall said, and showed that more attention needed to be paid to drug use by seniors, and to the health effects.“It’s somewhat in the shadows, and there is some ageism and bias in thinking that older adults aren’t using drugs,” Dr. Stall said.Edible marijuana samples at a cannabis testing laboratory in Santa Ana, Calif.Chris Carlson/Associated PressThe StudyThe study looked at 2,322 emergency room visits for cannabis poisoning among people 65 and older in Ontario. The visits spanned 2015 through 2022, allowing researchers to see what happened before and after October 2018, when Canada legalized the sale of dried cannabis, and January 2020, when the sale of edibles was legalized.In 2015, there were 55 emergency room visits caused by cannabis poisoning. That figure rose steadily to 462 by 2021, and then fell off slightly to 404 in 2022.Dr. Stall said he was motivated to undertake the study after being called into the emergency room to consult on an octogenarian who was experiencing severe confusion. The patient was barely conscious and showed strokelike symptoms. Multiple tests revealed no clear cause, until Dr. Stall ordered a toxicology test and found cannabis in the patient’s urine.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe. More

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      What Makes a Society More Resilient? Frequent Hardship.

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      Comparing 30,000 years of human history, researchers found that surviving famine, war or climate change helps groups recover more quickly from future shocks.From the Roman Empire to the Maya civilization, history is filled with social collapses. Traditionally, historians have studied these downturns qualitatively, by diving into the twists and turns of individual societies.But scientists like Philip Riris have taken a broader approach, looking for enduring patterns of human behavior on a vaster scale of time and space. In a study published Wednesday, these methods allowed Dr. Riris and his colleagues to answer a profound question: Why are some societies more resilient than others?The study, published in the journal Nature, compared 16 societies scattered across the world, in places like the Yukon and the Australian outback. With powerful statistical models, the researchers analyzed 30,000 years of archaeological records, tracing the impact of wars, famines and climate change. They found that going through downturns enabled societies to get through future shocks faster. The more often a society went through them, the more resilient it eventually became.“Over time, you will suffer less, essentially,” said Dr. Riris, an archaeologist at Bournemouth University in England. “There tends not to be wholesale collapse.”The researchers tracked the history of societies by taking advantage of the way archaeologists tell time. Most organic material, whether it’s charcoal or mussel shells, contains trace amounts of radioactive carbon-14, which gradually breaks down over thousands of years. By measuring the carbon-14 left at an archaeological site, researchers can estimate its age.This approach can also track population changes. As human groups get bigger, they burn more wood, eat more food and leave behind more garbage, all of which can be dated. When those groups shrink, their sites become rarer.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe. More

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      What Makes Tiny ‘Water Bears’ So Tough? They Quickly Fix Broken DNA.

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      New research finds that microscopic tardigrades are remarkably good at repairing their DNA after a huge blast of radiation.To introduce her children to the hidden marvels of the animal kingdom a few years ago, Anne De Cian stepped into her garden in Paris. Dr. De Cian, a molecular biologist, gathered bits of moss, then came back inside to soak them in water and place them under a microscope. Her children gazed into the eyepiece at strange, eight-legged creatures clambering over the moss.“They were impressed,” Dr. De Cian said.But she was not finished with the tiny beasts, known as tardigrades. She brought them to her laboratory at the French National Museum of Natural History, where she and her colleagues hit them with gamma rays. The blasts were hundreds of times greater than the radiation required to kill a human being. Yet the tardigrades survived, going on with their lives as if nothing had happened.Scientists have long known that tardigrades are freakishly resistant to radiation, but only now are Dr. De Cian and other researchers uncovering the secrets of their survival. Tardigrades turn out to be masters of molecular repair, able to quickly reassemble piles of shattered DNA, according to a study published on Friday and another from earlier this year.Scientists have been trying to breach the defenses of tardigrades for centuries. In 1776, Lazzaro Spallanzani, an Italian naturalist, described how the animals could dry out completely and then be resurrected with a splash of water. In the subsequent decades, scientists found that tardigrades could withstand crushing pressure, deep freezes and even a trip to outer space.In 1963, a team of French researchers found that tardigrades could withstand massive blasts of X-rays. In more recent studies, researchers have found that some species of tardigrades can withstand a dose of radiation 1,400 times higher than what’s required to kill a person.A preflight photo of a marine tardigrade as seen magnified by 40 times under a light microscope.Boothby Lab/ReutersWe are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe. More

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      No ‘Hippie Ape’: Bonobos Are Often Aggressive, Study Finds

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      Despite their peaceful reputation, bonobos act aggressively more often than their chimpanzee cousins, a new study found.In the early 1900s, primatologists noticed a group of apes in central Africa with a distinctly slender build; they called them “pygmy chimpanzees.” But as the years passed, it became clear that those animals, now known as bonobos, were profoundly different from chimpanzees.Chimpanzee societies are dominated by males that kill other males, raid the territory of neighboring troops and defend their own ground with border patrols. Male chimpanzees also attack females to coerce them into mating, and sometimes even kill infants. Among bonobos, in contrast, females are dominant. Males do not go on patrols, form alliances or kill other bonobos. And bonobos usually resolve their disputes with sex — lots of it.Bonobos became famous for showing that nature didn’t always have to be red in tooth and claw. “Bonobos are an icon for peace and love, the world’s ‘hippie chimps,’” Sally Coxe, a conservationist, said in 2006.But these sweeping claims were not based on much data. Because bonobos live in remote, swampy rainforests, it has been much more difficult to observe them in the wild than chimpanzees. More recent research has shown that bonobos live a more aggressive life than their reputation would suggest.In a study based on thousands of hours of observations in the wild published on Friday, for example, researchers found that male bonobos commit acts of aggression nearly three times as often as male chimpanzees do.“There is no ‘hippie ape,’” said Maud Mouginot, a biological anthropologist at Boston University who led the analysis.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe. More

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      New England Journal of Medicine Ignored Nazi Atrocities, Historians Find

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      The New England Journal of Medicine published an article condemning its own record during World War II.A new article in the New England Journal of Medicine, one of the oldest and most esteemed publications for medical research, criticizes the journal for paying only “superficial and idiosyncratic attention” to the atrocities perpetrated in the name of medical science by the Nazis.The journal was “an outlier in its sporadic coverage of the rise of Nazi Germany,” wrote the article’s authors, Allan Brandt and Joelle Abi-Rached, both medical historians at Harvard. Often, the journal simply ignored the Nazis’ medical depredations, such as the horrific experiments conducted on twins at Auschwitz, which were based largely on Adolf Hitler’s spurious “racial science.”In contrast, two other leading science journals — Science and the Journal of the American Medical Association — covered the Nazis’ discriminatory policies throughout Hitler’s tenure, the historians noted. The New England journal did not publish an article “explicitly damning” the Nazis’ medical atrocities until 1949, four years after World War II ended.The new article, published in this week’s issue of the journal, is part of a series started last year to address racism and other forms of prejudice in the medical establishment. Another recent article described the journal’s enthusiastic coverage of eugenics throughout the 1930s and ’40s.“Learning from our past mistakes can help us going forward,” said the journal’s editor, Dr. Eric Rubin, an infectious disease expert at Harvard. “What can we do to ensure that we don’t fall into the same sorts of objectionable ideas in the future?”In the publication’s archives, Dr. Abi-Rached discovered a paper endorsing Nazi medical practices: “Recent changes in German health insurance under the Hitler government,” a 1935 treatise written by Michael Davis, an influential figure in health care, and Gertrud Kroeger, a nurse from Germany. The article praised the Nazis’ emphasis on public health, which was infused with dubious ideas about Germans’ innate superiority.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe. More