Pushing Back Origins

6 Jul 2017

It seems the Out of Africa people are on the back foot once again. No doubt they will rebound but cracks are increasingly appearing in the idea that all modern humans have their origin in a movement out of Africa just 70,000 years ago. In fact, until recently it was thought to have occurred no earlier than 50,000 years ago - which became untenable, especially as Australian Aborigines appear to have been living in their landscape far at least that amount of time. At http://anthropology.net/2017/07/04/a-deeper-introgression-of-ancient-hum... ... ancient mtDNA studies from a 124,000 year old Neanderthal femur bone suggest modern human ancestors interbred with Neanderthals between 470,000 and 220,000 years ago. DNA from a 130,000 year old Siberian Neanderthal had genetic chunks that looked very much like those of modern humans, we are told - but modern humans, according to the consensus, did not go on walkabouts until 70,000 years ago. Hence, an early group of archaic modern humans left Africa much earlier and interbred with the Neanderthals, it is concluded. This is a serious blow to the current Out of Africa theory. How eill it react?

The same story is also at https://phys.org/print418360830.html ... and the study itself is published in Nature Communications (July 2017). Previously it was thought Neanderthals separated from modern humans at 700,000 to 550,000 years ago - yet they are now thinking in terms that archaic modern humans were actively breeding with them much more recently. Big change in thinking. It even sounds a bit like the multiple origins theory in that modern humans evolved in several different places around the world. One area in particular was central Asia (favoured by some as modern humans migrated out of this region following the demise of Neanderthals in Europe and western Asia around 40,000 years ago). The big question central to the mystery is rarely brought to the table, namely what role did catastrophism play in the die-off of Neanderthals and the appearance of modern humans. What is clear is that Neanderthals were much closer to modern humans in many ways previously denied. Archaeologists have recently found they even used toothpicks, which comes on top of many other traits they share with early modern humans. The new results are suggesting a split between modern humans and Neanderthals was as recent as 400,000 years ago, to account for the new shared genes. They say that Neanderthals were genetically more similar to modern humans that the Denisovans of Siberia (known from a finger bone). As they only have the one Denisovan bone to go by this appears to be a big leap of faith - rather than science. Others have seen the Denisovans have possessed traits similar to modern humans in Melanesia and Australia/New Guinea. Lots of information and research to come. With two sides to the debate one can expect a quicker solution - as competition will ensure each side gets their point of view across.