Homo Sapiens Have Been on Earth 100,000 Years Longer Than We Thought

This article originally appeared on Motherboard.

A site in Morocco has revealed the fossilized remains of at least five Homo sapiens—a classification that includes us modern living humans—dating back 300,000 years or maybe even longer. These would be the earliest fossils of Homo sapiens ever discovered.

This new research, described in two papers today in Nature, pushes back the timeline of human evolution by thousands of years, and throws a wrench in our current understanding of how the evolution of our species played out across the African continent.

An international team, led by Jean-Jacques Hublin of the Max Planck Institute for Evolutionary Anthropology and Abdelouahed Ben-Ncer of the National Institute for Archaeology and Heritage, discovered these fossils at a site called Jebel Irhoud, along with stone tools and animal bones (including gazelles and small mammals).

They found skulls, teeth and long bones from at least five people, using thermoluminescence dating on heated flints to figure out when they were from. By dating them back to 300,000 years ago, they've pushed back our species' origins by 100,000 years.

Jebel Irhoud has been home to other early hominid finds, in the 1960s. Originally, those fossils were thought to be from a different time period. Initial hypotheses suggested these were Neanderthal or another non- Homo sapiens. But none of the explanations fit the bill.

"The primary reason why I wanted to re-excavate this site was, first, to obtain a reliable dating, and second, to possibly find more material," said Hublin. "And we were very fortunate because the two expectations have been fulfilled."

The dating of Jebel Irhoud gives us a window into a time when multiple species of hominin shared the same continent. Now we know H. sapiens could have been among them.