The Sports Gene

Epstein explores racial differences in sports performance and examines both nature and nurture arguments for why certain populations (such as Jamaicans and Kalenjin) are overrepresented among top performers in the 100 meters sprint and marathons respectively. Epstein examines the argument that Kalenjin tend to have a body type conducive to distance running in part due to Allen's Rule. He also explores the contribution of growing up and training at altitude, as well as the phenomenon of running to and from school. In the course of his research, Epstein followed geneticist Yannis Pitsiladis to Jamaica, where he explored folklore that Jamaican sprinters descend from a warrior class of maroons. Pitsiladis analyzes DNA in Jamaica, and finds no special signature that links maroons and sprinters, and concludes that the genetic evidence does not support the island folklore. Rather, both Epstein and Pitsiladis place considerable emphasis on the popularity of the national high school track and field championships as part of the Jamaican sprint dynasty. In chapter 10 of the book, Epstein discusses problems with classifying athletes as simply "black," as he notes that there is more genetic diversity within Africa than in all of the rest of the world combined. He refers to work on global genetic diversity and migration from Yale's Kidd Lab to emphasize the point. He also notes that genetic diversity does not break down into discrete races in the way that people often assume.