How generous is an ape? It’s a hard question for scientists to tackle, but the answer could tell us a lot about ourselves.

People in every culture can be generous, whether they’re lending a cellphone to an office mate or sharing an antelope haunch with a hungry family.

While it’s easy to dwell on our capacity for war and violence, scientists see our generosity as a remarkable feature of our species. “One of the things that stands out about humans is how helpful we are,” said Christopher Krupenye, a primate behavior researcher at the University of St. Andrews in Scotland.

Continue reading “Seeking Human Generosity’s Origins in an Ape’s Gift to Another Ape” →

In a study carried out over the summer, a group of volunteers drank a white, peppermint-ish concoction laced with billions of bacteria. The microbes had been engineered to break down a naturally occurring toxin in the blood.

The vast majority of us can do this without any help. But for those who cannot, these microbes may someday become a living medicine.

The trial marks an important milestone in a promising scientific field known as synthetic biology. Two decades ago, researchers started to tinker with living things the way engineers tinker with electronics.

Continue reading “Scientists Are Retooling Bacteria to Cure Disease” →

In a limestone cave nestled high above the Anuy River in Siberia, scientists have discovered the fossil of an extraordinary human hybrid.

The 90,000-year-old bone fragment came from a female whose mother was Neanderthal, according to an analysis of DNA discovered inside it. But her father was not: He belonged to another branch of ancient humanity known as the Denisovans.

Scientists have been recovering genomes from ancient human fossils for just over a decade. Now, with the discovery of a Neanderthal-Denisovan hybrid, the world as it was tens of thousands of years ago is coming into remarkable new focus: home to a marvelous range of human diversity.

Continue reading “A Blended Family: Her Mother Was Neanderthal, Her Father Something Else Entirely” →

Elephants ought to get a lot of cancer. They’re huge animals, weighing as much as eight tons. It takes a lot of cells to make up that much elephant.

All of those cells arose from a single fertilized egg, and each time a cell divides, there’s a chance that it will gain a mutation — one that may lead to cancer.

Strangely, however, elephants aren’t more prone to cancer than smaller animals. Some research even suggests they get less cancer than humans do.

Continue reading “The ‘Zombie Gene’ That May Protect Elephants From Cancer” →

About 50 million years ago, dog-like mammals returned to the seas, eventually evolving into whales and dolphins. Around then, too, an early cousin of elephants took the plunge, giving rise to manatees and dugongs.

About 20 million years later, bearlike mammals also waded back into the sea, evolving into seals, sea lions and walruses.

Each of these marine species adapted to the aquatic life in its own way. Manatees and dugongs slowly graze on sea grass. Seals and their relatives dive deep underwater after prey, but still haul themselves onto beaches to mate and rear pups.

Continue reading “Marine Mammals Have Lost a Gene That Now They May Desperately Need” →