Colin Renfrew on recent human evolution

Colin Renfrew is an archaeologist, in recent years well-known for his work on Neolithic Europeans and Indo-European origins. Last week, someone pointed me to his recent book, Prehistory: The Making of the Human Mind. I read a short review somewhere, but I’ve lost the link!

The book was first published in 2007, so its writing would have predated the publication of recent scans of the genome for selection. Renfrew of course has his own distinctive point of view, and he is not himself a geneticist. However, he has worked to integrate his work with genetic insights, interacts closely with many geneticists, and even coined the term, archaeogenetics, to describe a certain kind of gene-driven investigation of population history. So he’s no neophyte when it comes to how geneticists describe the evolution of recent human populations.

A number of passages of the book are very interesting, from the perspective of the conventional wisdom about recent human evolution. I wanted to cite these paragraphs from page 92:

The genetic composition of living humans at birth (the human genotype) is closely similar from individual to individual today. That was an underlying assumption of the Human Genome Project and it is being further researched in studies of human genetic diversity. We are all truly born much the same. Moreover a child born today, in the twenty-first century of the Common Era, would be very little different in its DNA -- i.e., in the genotype, and hence in innate capacities -- from one born 60,000 years ago.

Then on page 93, after some additional discussion of Neandertal genetic results:

The implication here must be that the changes in human behaviour and life that have taken place since that time [between 60,000 and 100,000 years ago], and all the behavoural diversity that has emerged -- sedentism, cities, writing, warfare -- are not in any way determined by the very limited genetic changes which, as we understand the matter, distinguish us from our ancestors of 60,000 years ago. So the differences in human behaviour that we see now, when contrasted with the more limited range of behaviours then, are not to be explained by any inherent or emerging genetic differences. Modern molecular genetics suggests that, apart from the normal distribution range present in all populations in matters such as IQ, all humans are born equal.

This represents a widespread point of view, one with a long pedigree in archaeology and human genetics (refer also to my post on Ashley Montagu). Renfrew quite clearly claimed that human evolution stopped once humans became “modern”. He emphasizes this point as the basis of a “paradox” – the observation that no large anatomical changes correlate with the increase in archaeological complexity of the last 30,000 years.

I believe there is no paradox: rapid archaeological change certainly is no proof of evolutionary stasis!