Cochran & Harpending's "The 10,000 Year Explosion"

This is a book I couldn't put down. I ended up putting off lots of things while I found time to finish this book. It is an excellent and exciting account of evidence for genetic evolution in modern humans.

The main argument is:

• The proposed that the "creative explosion" of 40,000 years ago was the result of gene interchange with the Neanderthals.


• The rapid explosion of population with agriculture created an opportunity for genetic innovation and the pressures for new behaviours required by farming did the selecting to shape a genetically new human


• The conquest of the new world was greatly facilitated by disease which in fact was evidence of very different immune system genetics between New World populations that never felt the selective pressures of Old World population densities of the agricultural explosion


• The expansion of the Indo-Europeans is evidence of the genetic value of genes that prolonged the ability to digest lactose


• The near one standard deviation superiority in IQ among Ashkenazi Jews is evidence of evolutionary pressure selecting for intelligence among an socially isolated population forced to live by its wits among an fiercely anti-Semitic European population

I enjoyed numerous other details about genes sprinkled throughout the book:

• Light skin is not an adaptation for "living in the north" as is commonly thought (think Inuit who are still dark and stories by the Romans that Picts were "dark skinned"). It was a vitamin D deficiency caused by the change of diet to cereals by the agricultural revolution that put evolutiony pressure to select for lighter skin to allow more vitamin D production in the skin to make up for the lack in the diet


• The Romans dispatched a large number of Sarmatians to an outpost in England. This can be seen in the genetics of the English populations and in stories that strangely match the tales found in the Caucasus. He cites the Arthurian legend as curiously matching a tale of a dying warrior who wants his sword to be thrown into a lake. Twice his friend fails to do the deed. With much pleading he finally throws it into the lake and a woman's hand come up out of the lake and grabs it.


• The authors argue that 10,000 years ago there were no light coloured eyes. But blue eyes result from a change in the expression of the HERC2 gene which lies next to the OCA2. The HERC2 regulates the expression of the OCA2 gene which controls eye colour. The authors argue that this mutation occurred 6,000 years ago within Lithuania among the Vandal tribe which then spread it throughout western Europe and into North Africa where it shows up among the Berber people.

This is a fascinating book. I highly recommend it. It gives you a new twist on history and on understanding the evolutionary history of modern humans.