I'm thinking a lot about species concepts as applied to humans, about the "Out of Africa" model, and also looking back into Africa itself. I think the idea that modern humans originated in Africa is still a sound concept. Behaviorally and physically, we began our story there, but I've come around to thinking that it wasn't a simple origin. Twenty years ago, I would have argued that our species evolved in one place, maybe in East Africa or South Africa. There was a period of time in just one place where a small population of humans became modern, physically and behaviourally. Isolated and perhaps stressed by climate change, this drove a rapid and punctuational origin for our species. Now I don’t think it was that simple, either within or outside of Africa.There is a 44' video at the site (which I haven't viewed yet).
UPDATE: at 10:45, he suggests that Broken Hill is much younger than "many of us think". This seems exceptionally important, since BH (or Kabwe) is thought to be the African branch of H. heidelbergensis and a precursor to the later H. sapiens. Given the current extent of dates proposed for the specimen, it seems almost certain that "much younger" means post-Omo, and hence: (i) one possible precursor for H. sapiens disappears from Africa, and (ii) one additional post-H. sapiens archaic hominin is added.
It makes perfect sense to me to think of back migrations. This has happened over and over again in history. When I look at my maternal L3b1a (at the HVR I & II as well as the SNP's), it is suggestive of multiple layers of placements. The notion of L3 going from East Africa to the Levant/Arabia back to North South and West Africa is more than plausible considering all the climatic changes that have occurred in the last 60 kya. All these African/Middle eastern layers show up time and time again. I believe the are historical and reflect a prehistorical and ancient pattern of migration and back migration.
ReplyDeleteThe dating of the Kabwe skull at 110kya by direct methods seems pretty solid. If we were to pick a date that I doubted in human evolutionary physical anthropology, this wouldn't have been one I would have picked.
ReplyDeleteComing from Chris Stringer that is a real change around.
ReplyDelete"Twenty years ago, I would have argued that our species evolved in one place, maybe in East Africa or South Africa. There was a period of time in just one place where a small population of humans became modern, physically and behaviourally. Isolated and perhaps stressed by climate change, this drove a rapid and punctuational origin for our species".
I've just commented on that idea at a more recent post about the Klasies River hominins. Seems even Chris Stringer is beginning to see it the same way:
"Now I don’t think it was that simple, either within or outside of Africa".
I'd be very surprised if anything in biology was particularly simple.