Human Origins

31 Jul 2012

At www.nytimes.com/2012/07/27/science/cousins-of-neanderthals-left-dna-in-a... ... the New York Times reports on the study in the journal Cell (see a couple of days ago) and they fill out some of the detail. Palaeo-anthropologists, using bone fossils, have established modern humans arose in Africa 200,000 years ago. In Africa, it is then supposed in the consensus model, all archaic species of humans died out. They survived only outside Africa - such as the Neanderthals in Western Asia and Europe. As preposterous as this might sound, on the face of it, anthropologists jealously guard their model, formed from bone fragments and the odd skull. They don't like the new study in Cell it would seem, although Chris Stringer from the Natural History Museum appears quite unfazed by the findings. The new study upsets the consensus, or the working paradigm of anthropologists around the world. The study claims an otherwise unknown archaic species of human, a cousin of the Neanderthals, may have survived in Africa until around 25,000 years ago, co-existing with modern humans and even interbreeding with them. This is based on genetics. Geneticists have upset anthropologists by assuming their evidence is more trustworthy than fossilised bone. Indeed, genetics is probably over-rated, especially where it comes to dating and pinpointing when genetic change might have occurred. Be that as it may, the main threat of the study is that it implies modern humans were not really modern humans until fairly late in the Pleistocene - perhaps at the same time that Neanderthals ceased to be Neanderthals and were replaced by modern humans. Nobody is actually saying this, as yet, and the genetic trace is quite small (but it all happened a long time ago).

In addition, the criticism levelled by anthropologist Richard Klein, is placed by the journalist in a different perspective than in the news blurb accompanying the publication of the paper - and all credit to the journalist in question. Klein said the findings were 'irresponsible' because the geneticists published their results without trying to fit the new evidence into the existing fossil and archaeological evidence. In other words, they didn't attempt to fit the genetics into the consensus model.