Israeli scientists find oldest evidence of hybrid between Homo sapiens and Neanderthals
Scientists discovered signs of interbreeding between Neanderthals and Homo sapiens on a 140,000-year-old skull; 'This is the world's earliest evidence of a connection between these two human groups'
An international Tel Aviv University (TAU) study in collaboration with the French National Center has published Wednesday that a skull belonging to a 5-year-old boy who lived 140,000 years ago is the first evidence that Neanderthals and Homo sapiens had biological and social interactions, and even interbred.
The researchers discovered a combination of features charactaristic of both species in the skull of the five-year-old boy discovered in the Sahuol (Hagdi) Cave in Carmel about 90 years ago.
This is the oldest human fossil in the world that shows morphological features of both of these human groups.
"Genetic studies from the last decade show that these two groups exchanged genes with each other," explained Professor Israel Hershkowitz of TAU. "Even today, 40,000 years after the last Neanderthals disappeared, part of our genome, 2 to 6 percent, is of Neanderthal origin. But this gene exchange refers to a much later time period - 40-60,000 years before our time. Here we are talking about a 140,000-year-old human fossil."
The charactaristic that led to the breakthrough discovery was in the boy's head. "In the study, we show that the skull, whose general shape resembles Homo sapiens, especially in the curvature of the cranial box, has an intracranial blood supply system, lower jaw, and inner ear structure that are characteristic of Neanderthals."
For years, Neanderthals were considered a group that evolved in Europe, whose representatives migrated to the Land of Israel only about 70,000 years ago, following the spread of glaciers in Europe. In a groundbreaking study published in 2021, Hershkowitz and his colleagues showed that ancient Neanderthals lived in the Land of Israel as early as 400,000 years ago.
This type of man, which Hershkowitz called "Ramla Eagle Man," after the archaeological site where it was found -- near the Ramla Eagle Plant -- encountered the Homo sapiens groups that began to leave Africa about 200,000 years ago -- and according to the findings of the current study, interbred with them.
The researchers reached this conclusion after a series of advanced tests they conducted on the fossil. First, they scanned the skull and jaw with micro-CT, and from the scans they assembled an accurate 3D model of them. This allowed the researchers to conduct an analysis of the anatomical structures and compare them to different human populations. In addition, they even created an accurate 3D structure of the interior of the skull.
"The fossil is the earliest known physical evidence of interbreeding between Neanderthals and Homo sapiens," said Hershkowitz. "In 1998, a skeleton of a child was discovered in Portugal that shows features of both these human groups. However, this skeleton dates back to 28,000 years ago - more than 100,000 years later than the child from Skol."
"Traditionally, anthropologists associate the fossils in Sahull Cave with an ancient group of Homo sapiens. The current study reveals that at least some of them are the result of ongoing gene infiltration from the local – and long-standing – Neanderthal population into the Homo sapiens population."