Professor of Archaeological Science and Deputy Director of the Oxford Radiocarbon Accelerator Unit Tom Higham talks about what we know about the journey from a number of different ancient human-like species to modern humans today – Homo sapiens sapiens.
PROF TOM HIGHAM
Humans evolved in Africa, I’d say around 200,000 years ago, and then perhaps around 50 to 60,000 years ago, we made this move around the world, and we populate the world all over. This crucial period between 60,000 and 30,000 years ago where we go from a number of hominins to just one.
Everyone in the world is modern Homo sapiens sapiens, but we have this intriguing evidence for genetic exchange or gene flow between different archaic populations that lived outside Africa prior to our movement out of Africa. And these include Neanderthals and Denisovans, and these little variable proportions of DNA that we get from these people come with us today, and we can now intriguingly map and identify what the function of these genes that we inherit from them are today, and this is the subject of active research.
60,000 years ago, humans like us weren’t the only humans on the planet. There were several others. Homo floresiensis, for example – a diminutive 1.1 metre-high hominin that lived only on the island of Flores. Neanderthals, of course – the archetypal caveperson – anatomically modern humans, of course, like us – and finally a mysterious new hominin that appeared on the scene in 2010 – Denisovans. We don’t have a face for Denisovans yet, because the fossil record is very silent on them. We only have one small finger bone and three teeth at the moment of the Denisovans, so we have to have a lot more fossil evidence before we can put a face and reconstruct what we think these people look like.
The Science Learning Hub would like to acknowledge:
Professor Tom Higham, University of Oxford
The Allan Wilson Centre for Molecular Ecology and Evolution
Human family tree diagram, © The Trustees of the Natural History Museum, London
Model of H. floresiensis courtesy of S Estressangle/E Daynes
Models of Neanderthal man and ancient H. sapiens sapiens man, © The Trustees of the Natural History Museum, London/Kennis & Kennis Reconstructions
Silhouette of hooded man, Rangizzz, licensed through 123rf Ltd
Photo of Denisovan finger bone, Max Planck Institute for Evolutionary Anthropology