Posted on March 24, 2006

Winters Are Good For Your Genes

J. Philippe Rushton, VDARE, March 22, 2006

Four years ago, via, I was able to give the first significant publicity to IQ and the Wealth of Nations, the luminous book on IQ and the diverging economic performance of different countries co-authored by Richard Lynn with Tatu Vanhanen. Now Professor Lynn has followed up with another important book, Race Differences in Intelligence: An Evolutionary Analysis.

Its central finding: the world average IQ is no more than 90, equivalent to the mental age of a white 14-year-old. (Standardized IQ tests are normed to 100, the mental age of the average white 16-year-old.) Lynn also draws attention to the fact that a north-south IQ continuum has evolved, apparently through selection for survival in cold winters.

These findings in Lynn’s latest book have profound geopolitical significance. They imply it may simply not be possible to transmit Western-style democratic and economic systems to the populations of Latin America and Moslem North Africa and the Middle East, let alone sub-Saharan Africa. They mean that the world’s long-term problems will stem from its populations’ capabilities — much deeper and more intractable than any “Clash of Civilizations”-style competition between different political concepts.

The implications for immigration are obvious: it can have fundamental, and permanent, consequences.

For Lynn, Race Differences In Intelligence represents the culmination of more than a quarter of a century’s work on intelligence. It was in 1977 that he first ventured into this field — some would say minefield — with the publication of two papers on IQ in Japan and Singapore. Both showed that the East Asians obtained higher averages than White Europeans in the United States and Britain. These initial studies were disputed, but the present book lists 60 studies of the IQs of indigenous East Asians, all of which confirm the original contention. IQ and the Wealth of Nations showed that variation in IQ largely explains the problem of why some countries are rich and others poor. More recently, Lynn has helped overturn the century-long consensus that there is no average sex difference in intelligence by showing that men average 4 to 5 IQ points higher than women. (E.g. Lynn & Irwing, 2004, “Sex Differences on the Progressive Matrices: a meta-analysis,” Intelligence, 32, 481-498. [pay archive] This finding is controversial even by the standards of the IQ debate — I hope to write about it soon in VDARE.COM.)


As early humans migrated out of Africa they encountered the cognitively demanding problem of having to survive cold winters where there were no plant foods and they had to hunt, sometimes big game. They also had to solve the problem of keeping warm. This required greater intelligence than was needed in tropical and semi-tropical equatorial Africa where plant foods are plentiful throughout the year. Lynn shows that race differences in brain size and intelligence are both closely associated with low winter temperatures in the regions they inhabit. He gives a figure of 1,282 cc for the average brain size of sub-Saharan Africans, as compared with 1,367 cc for Europeans and 1,416 cc for East Asians.