Five years ago, on a remote island in Wales, University of Oxford scientist Annette Fayet spied a puffin doing something she had never seen before. The bird held a stick in its beak and began to scratch. The puffin was using a tool.

As unusual as this was, Fayet said, she “kind of forgot about it.” Until it happened again. In July 2018, Fayet was studying puffins at Grimsey Island in Iceland, about a thousand miles from Wales.

Another puffin used a scratching stick. This time, the action unfolded in front of a camera: The bird spots a stick and grasps it with a cartoon-bright beak. The bird makes a burbling sound. It turns, as if to face the lens. And then it scratches its chest feathers with the stick’s pointy end.

This behavior “fits all current definitions” of tool use, said University of Oxford zoologist Alex Kacelnik.

Dora Biro, an animal behavior expert at the University of Oxford, said the video was exciting because “this was a puffin, this was a seabird — and tool use had never been reported in seabirds before.”

Scientists have observed tool use in fewer than 1% of species. And back-scratching is an unusual form of tool use that the scientists called “body care.” The puffin may have been trying to rid itself of ticks, they said.

Are some wolf pups just more playful?

Scientists have not discovered a new cave painting of the first game of fetch between dog and human. But Christina Hansen Wheat and Hans Temrin, biologists at Stockholm University, have found something almost as intriguing. They observed 8-week-old wolf puppies retrieve a ball at the urging of a stranger, without training.

Only three of 13 pups, over several years of testing, played fetch. And they were far from perfect. But the researchers say that if the ability to engage with people this way is present in some wolves, it seems likely that it was present in the ancient wolves that were the ancestors of dogs, rather than evolving from new mutations during domestication.

This is the first evidence of this kind of responsiveness in untrained wolves, Hansen Wheat said.

Connecting DNA of human family tree

In 2015, scientists created a complete genetic snapshot of an African from an ancient skeleton by recreating the genome of a 4,500-year-old man who lived in Ethiopia.

Now researchers have found the first genetic material from West Africa. A team reported that they had recovered DNA from four individuals in Cameroon, dating back as far as 8,000 years. In the new study, published in Nature, researchers reported that modern humans diverged into four major populations between 200,000 and 250,000 years ago. One of those populations is new to scientists; few traces of it remain in the DNA of living Africans.

Scientists have struggled to draw the older branches of the human family tree with much precision. Now David Reich, a Harvard Medical School geneticist, and archaeologist Mary Prendergast traced the major linages of people to ancestors who lived in Africa between 200,000 and 250,000 years ago. One lineage passed down its DNA to living hunter-gatherers in southern Africa. A second group comprises the ancestors of central African hunter-gatherers. A third became hunter-gatherers in East Africa.

The fourth group, which researchers call “Ghost Modern,” is far more mysterious. The ancient Shum Laka people have a substantial amount of that ancestry. So do the ancient Mota from Ethiopia. But ancient remains from Morocco and South Africa had none. It’s possible that the Ghost Moderns lived across the southern edge of the Sahara, isolated for tens of thousands of years.

News services