Are you part Neanderthal?
- Origin of Our Species by Chris Stringer
Allen Lane, 333 pp, £20.00, June 2011, ISBN 978 1 84614 140 9
Lucky Chris Stringer, to have spent the last forty years immersed in new discoveries about the origin of our species. I don’t suppose that when he began his PhD research in 1970, setting off on a tour around the museums of Europe to measure as many skulls as he could get his hands on, he imagined that today he would need to be as conversant with mutations on the Y chromosome as he is with the shape of the pubic ramus (part of the pelvis). Or that we would now be able to establish the diet of our remote ancestors by analysing the chemistry of their bones, or to examine the structure of the minute inner ear bones of fossil skulls by means of computerised tomography. Or that it would now be possible to use luminescence techniques to date single grains of sand. Stringer’s mobile phone has more processing power than the multi-room University of Bristol computer he used in the 1970s to undertake one of the first applications of multivariate statistics on human fossils – something we would now expect undergraduates to do.
Stringer played a pivotal role in the formulation of a ‘Recent African Origin’ model for Homo sapiens – the species to which everyone alive today belongs. By suggesting that we had a single and recent origin in Africa, he was opposing the 1980s trend towards a multiregional model for human origins, which had originally been proposed by Franz Weidenreich in the 1930s. Weidenreich suggested that each population of Homo erectus around the world had evolved into its own variant of Homo sapiens, with its own distinctive racial characteristics. Both the Recent African Origin and the multiregional model come in several variants, but the basic contrast has framed research into human origins throughout the last three decades. That research has been diverse: new fossil discoveries and archaeological excavations, new dating methods, new procedures for the extraction of ancient DNA and so on. Stringer’s account is made all the more impressive by his having been involved in so many groundbreaking projects of every type – archaeological, fossil and genetic.
The major players in Stringer’s story are Homo erectus, the first human to disperse out of Africa sometime after two million years ago; Homo heidelbergensis, a descendant of Homo erectus and most probably the common ancestor of the Neanderthals and ourselves; Homo neanderthalensis, found in Europe and South-West Asia, which appears so biologically similar and yet so culturally different from ourselves; and finally Homo sapiens. He charts the advances in our understanding of the fossil, archaeological and genetic evidence in turn, before bringing all the evidence together in the most up to date synthesis available. Genetics – both ancient and modern – has made by far the most dramatic advances since I was last closely involved with the subject a decade ago, but there have also been impressive developments in the dating and analysis of fossils. In contrast, the chapters dealing primarily with the archaeological evidence, and focusing on what it can tell us about language, thought and symbolism, have a familiar air: there is only a limited quantity of new data and although the terminology is new, the arguments are not. It is striking that very little has been learned from the analysis of stone artefacts, once by far the most abundant source of evidence for past behaviour, over the last thirty years.