A million-year-old skull reveals new insights into human evolution.

 

skull

A million-year-old skull reveals new insights into human evolution.

A digital reconstruction of a million-year-old skull shows that humans may have diverged from their ancient ancestors 400,000 years earlier than previously thought, and in Asia rather than Africa, according to a new study published Friday.

The study's authors also explained that these conclusions are based on a reconstruction of a crushed skull discovered in China in 1990, and could resolve the mystery called the "mesopause" that has long shrouded human evolution.

"Yanxian 2"

The skull, dubbed "Yunxian 2," was previously thought to belong to a human ancestor known as Homo erectus.

But modern reconstruction techniques used by a team of researchers have revealed traits closer to species previously thought to have existed later in human evolution, including the recently discovered Homo erectus and Homo sapiens, the modern-day Homo sapiens.

"distinct groups"

For his part, Chris Stringer, an anthropologist at the Natural History Museum in London, who was part of the research team, explained that this discovery "changes a lot of ideas."

"This shows that our ancestors split into distinct groups a million years ago, meaning that the human evolutionary split is much older and more complex than previously thought," Stringer added.

If the results are correct, they suggest the possibility of individuals much older than other early hominins, including Neanderthals and Homo sapiens.

However, it also undermines long-held assumptions that early humans spread out of Africa, according to Michael Petraglia, director of the Australian Centre for Human Evolution Research at Griffith University, who was not involved in the study.

"a big change"

"These findings could potentially be a game changer if East Asia plays a major role in hominin evolution," Petraglia told AFP.

The study, published in the journal Science, used advanced computed tomography, structural light imaging, and virtual reconstruction techniques to model the entire skull of Yanxian 2.

The scientists also relied in part on another similar skull to form their model, and then compared it to more than 100 other specimens.

"A different mix of traits"

The resulting model "shows a diverse mix of features," some similar to Homo erectus, including a protruding lower face, the study said.

However, other aspects, including a larger brain capacity, are closer to Homo erectus and Homo sapiens, according to the researchers.

Stringer also explained that "Yanxian 2 may help resolve the so-called 'intermediate chaos,' a term referring to confusion arising from a group of human fossils dating back between 1 million and 300,000 years."

"Fossils like Yanxian 2 show that we still have much to learn about our origins," he concluded in a statement.