Yesterday we published a slightly peevish piece on early human migration. We pointed to all the different species, all the different tool assemblages and all the scattered sites across Eurasia, and bemoaned the implausibilities of the various theories which have been adduced to try to link them all up.
About an hour later a regular update from Nature Briefings dropped into our in-box. And what it contained blew us away. Read this:
Humans did not emerge from a single region of Africa, but from several populations that moved around the continent one million years ago and intermingled for millennia. The widely held idea of a single origin of Homo sapiens is based in part on fossil records. Computer modelling and genome data from modern African and European populations revealed that “our roots lie in a very diverse overall population made up of fragmented local populations”, says evolutionary archaeologist Eleanor Scerri. This means human evolution looks more like a tangled vine than a ‘tree of life.’Nature | 4 min read
Reference: Nature paper
OK, the authors are talking about the situation 1 million years ago and the emergence of Homo sapiens in particular, not 2 million years and the emergence of the Homo genus. But the message is the same for both. If you spend your time looking for this specimen, which made that tool kit, which makes your discovery the key ancestor of us all, you are wasting your time. It looks like our tree is a ramifying bush of wondering tribes, some of whom may have changed shape a bit in response to various ecological and environmental pressures. Rivers flooded, volcanoes went off, droughts scorched the earth. The survivors were driven into the arms of other groups-and genes and ideas flowed as they have always done. After all it took humans and chimpanzees about three million years to finally give up interbreeding. What was to stop a few Homo habilis types getting up to monkey business with some itinerant Denisovan folk, if the mood took them?
We suspect the real problem arose from the fact that early investigators were trained in the old school. Where every new discovery, plant, animal or fungus had to be given a new species name, with a Latin binomial- Felis domesticus, Quercus robur, or whatever. Don’t get us wrong: naming things is incredibly important and useful. We think Linnaeus was one of the all time greats. But there comes a point at which getting hung up on names and labels is no longer helpful. In fact it affords the opposite of true understanding. Locally that’s true in human evolution. We hope people might laern this lesson a little more widely. And thanks to Nature Briefings for showing the point to us.
#nature briefings #human evolution #homo sapiens #homo erectus #classification #tool cultures #acheulian #oldowan
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