A tooth found inside of a mountain cave in Laos has solved one of the biggest scientific mysteries of the Denisovans, a branch of ancient humans that disappeared roughly 50,000 years ago.

Since 2010, when Denisovan teeth and finger bones were first discovered, DNA testing has revealed that the enigmatic hominins were among the ancestors of people alive today in Australia and the Pacific.

But scientists didn’t understand how the Denisovans, whose scant remains had been found only in Siberia and Tibet, would have been able to interbreed with the group of humans who expanded east from Africa through Southeast Asia before reaching Australia, New Guinea and other islands in the Pacific. Continue reading “Tooth of an Ancient Girl Fills Gap in Human Family Tree” →

Over the next 50 years, climate change will drive thousands of viruses to jump from one species of mammal to another, according to a study published in Nature on Thursday. The shuffling of viruses among animals may increase the risk that one will jump into humans and cause a new pandemic, the researchers said.

Continue reading “Climate Change Will Accelerate Viral Spillovers, Study Finds” →

Over the next 50 years, climate change will drive thousands of viruses to jump from one species of mammal to another, according to a study published in Nature on Thursday. The shuffling of viruses among animals may increase the risk that one will jump into humans and cause a new pandemic, the researchers said.

Scientists have long warned that a warming planet may increase the burden of diseases. Malaria, for example, is expected to spread as the mosquitoes that carry it expand their range into warming regions. But climate change might also usher in entirely new diseases, by allowing pathogens to move into new host species.

“We know that species are moving, and when they do, they’re going to have these chances to share viruses,” said Colin Carlson, a biologist at Georgetown University and a co-author of the new study.

Continue reading “Climate Change Will Accelerate Viral Spillovers, Study Finds” →

Colin Carlson, a biologist at Georgetown University, has started to worry about mousepox.

The virus, discovered in 1930, spreads among mice, killing them with ruthless efficiency. But scientists have never considered it a potential threat to humans. Now Dr. Carlson, his colleagues and their computers aren’t so sure.

Using a technique known as machine learning, the researchers have spent the past few years programming computers to teach themselves about viruses that can infect human cells. The computers have combed through vast amounts of information about the biology and ecology of the animal hosts of those viruses, as well as the genomes and other features of the viruses themselves. Over time, the computers came to recognize certain factors that would predict whether a virus has the potential to spill over into humans.

Continue reading “Which Animal Viruses Could Infect People? Computers Are Racing to Find Out.” →

This year marks the 40th anniversary of “Chimpanzee Politics,” a book that forced us to look at our simian cousins in a new light. The author, a Dutch primatologist named Frans de Waal, offered an unprecedented look at the social world of chimpanzees. Their lives are crammed with alliances, betrayals, and Machiavellian maneuvers. “Chimpanzee Politics” was also the debut of a gifted writer. De Waal turned what might have been a dry monograph into something that read more like a character-packed novel.

De Waal has been busy in the four decades since. He has studied other primates, such as bonobos, a species that split from the chimpanzee lineage about two million years ago. Unlike chimpanzee societies, in which males typically dominate, bonobo societies turn out to be run by the females.

Continue reading “Primate Societies Are Surprisingly Complex. So Are Their Gender Roles.” →