Some 55,000 years ago, a person — whether female or male, we don't know — lived in Manot Cave in the western Galilee area of what is now Israel. Judging from the partial skull recovered from the cave, and described in Nature last week by Israel Hershkovitz of Tel Aviv University and his co-authors, the person was anatomically modern and closely related to the first modern humans who went on to colonize Europe.
Greedy for any solid evidence that sheds light on the migration of anatomically modern humans (AMH) out of Africa and into Europe, paleoanthropologists welcome detailed analysis like this one about the Manot Cave person (known as "Manot 1").
For the rest of us, there's something exciting about scientific announcements like this because they afford us new glimpses of our very own evolutionary path.
Let's consider what paleoanthropologists knew already, before the discovery of the Manot 1 skull.
AMH — people like us — evolved in Africa right around 200,000 years ago from earlier human-like ancestors. For many millennia, Africa remained the center of our evolution — and not just anatomically: The fascinating paint factory found at Blombos Cave in South Africa, dated to 100,000 years ago is just one illustration of the behavioral and cognitive sophistication that developed in Africa.
By about 45,000 years ago, AMH had reached Europe in a migration out of Africa. Europe had, of course, been inhabited before that time by other human-like species including Homo heidelbergensis, but we ourselves only arrived at this relatively late period. Within about 15,000 years, at places like Chauvet Cave in France, our AMH ancestors were painting cave walls with gloriously colorful, highly accurate representations of animals.
But how can we understand something about that initial migration and the people who made it? Here's where Manot 1 comes in. Israel was part of a key evolutionary landscape for our species, in part because of the travel corridor in the Levant region through which migrants passed out of Africa. Lead author Hershkovitz told The New York Times last week that the Manot cranium "is the missing connection between African and European populations."
In other words, as the Times also emphasized, in this new discovery we have the very first fossil evidence of the "out of Africa" migration at this critical time period. That's big news.
Certain details of the skull anatomy, as reported in Nature, are particularly significant. The skull has what's called an occipital bun, a particular shape at the skull base that is, Hershkovitz and his co-authors write, "a feature very frequently found both in European Neanderthals and in the majority of Upper Paleolithic modern humans." This feature sets the skull apart from those of other AMH living in the Levant at the same time, and links the Manot person to Europe.
But it also links Manot 1, at least potentially, to Neanderthals, who also lived in the same region. And here, the Nature team's conclusion is circumspect: "The Manot 1 specimen could potentially represent a hybrid between AMH's and Neanderthals."
This cautious stance is warranted, because with only a single partial skull, inferences about interbreeding are necessarily limited. But as anthropologist, John Hawks, who has written more technically about the Manot find than I am capable of doing, shows it's not news that interbreeding happened consistently between different ancestral populations throughout relatively recent human evolutionary history; it's just that Manot 1 may or may not be an example of that process.
What we're left with is this: a clearer picture of how we AMH spread out from our African home and began the process of colonizing other parts of the world. We have long been wanderers — and the 55,000-year-old Manot cranium is a striking material pointer to that wanderlust.
Barbara J. King, an anthropology professor at the College of William and Mary, often writes about human evolution, primate behavior, and the cognition and emotion of animals. Barbara's most recent book on animals was released in paperback in April. You can keep up with what she is thinking on Twitter: @bjkingape.