Bruce Bower last week had a nice article about the new Misliya Cave dating in Science News: “An ancient jaw pushes humans’ African departure back in time”.
The story in a nutshell is that a demi-maxilla from Misliya has been placed between 177,000 and 194,000 years ago. The teeth lack any close similarity with Neandertal teeth and are modern in size, and the morphology of the bone doesn’t resemble European Neandertals. That makes it indistinguishable from the cranial material from Qafzeh and Skhul, which are only between 90,000 and 110,000 years old. Up to double their age, the Misliya maxilla could be the earliest modern human outside Africa.
But I’m not so sure:
Hawks isn’t so sure the jaw belongs to H. sapiens. Interbreeding between H. sapiens, Neandertals and perhaps other Homo species in the Middle East could have produced a hybrid Misliya population characterized by humanlike jaws connected to bulkier, Neandertal-style bodies, Hawks says.
Or a Homo species closely related to H. sapiens — but not known from any previous fossils — may have traveled to Misliya Cave, he speculates. “This new discovery from Misliya Cave raises more questions than answers,” Hawks says.
I’m writing more on the implications of this discovery in the context of other recent work. There is a major change underway in how we understand “out of Africa”. I don’t think the traditional framing of “out of Africa” is very effective anymore, as leaving Africa is a tiny event, repeated many times over the last several hundred thousand years.
In the context of other discoveries, I think that “modern human” has lost much of the meaning it may once have had.
The big questions concern what was happening inside Africa, where many genetically diverse populations existed and interacted. How many ancestral populations gave rise to the growing population of modern humans after 100,000 years ago? How many African-derived people were involved in mixture with Neandertals 250,000 years ago, or 120,000 years ago? Did African-derived humans make it to China, or to Java, before 100,000 years ago?
Those are open questions, with some evidence pointing toward faster, more widespread dispersal, more mixture, and repeated genetic replacements.