It's Kenya's national sport, a kind of national obsession. From a tiny age, young Kenyans dream of the roar of the crowd, the fame and success that comes from demonstrated excellence on the field.

Conventional thinking--and quite a few liberal academics--hold that this cultural obsession is the best explanation for the incredible Olympic success of Kenya's distance runners. Kenya in particular, and East Africa in general, enjoys a near-monopoly in medals in the long distance races.

The only problem--pointed out by John Entine in his fascinating book Taboo--is that the national obsession in Kenya is not running but soccer. Kenyans are crazy about soccer! "Unfortunately," Entine observes, "Kenyans are among the world's worst soccer players." Even in Africa, Kenya is routinely routed by West African countries like Cameroon and Nigeria.

Running is not such a big deal in Kenya. And when it comes to short-distance sprints, Kenyans and other East Africans aren't particularly good. Virtually every running record from the 100 to the 400 meters, male and female, is held by athletes of West African ancestry. It's only in the 5,000 meters, 10,000 meters and in the marathon that the special abilities of East African runners manifest themselves.

Entine, an Emmy winning journalist formerly with NBC News, has done his homework. He does not completely reject economic and cultural explanations of athletic prowess. He just shows their inadequacy. For instance, examing the notion that poverty is responsible for success in sport, Entine notes that most poor countries do terribly in sports. How many runners from poverty-stricken Bangla Desh, for instance, have won Olympic medals in Beijing? The "spur" of poverty is more than trounced by the benefits of superior nutrition, superior facilities and superior coaching in affluent countries.

So what about culture? Yes, culture can help to account for why Americans do well at baseball and why the Chinese usually triumph in ping pong. Americans play baseball more than most others, and no one takes ping pong more seriously than the Chinese. But Entine notes that running is universal. In every country, young people run races. "Given the universality of running," Amby Burfoot writes in Runner's World, "it is reasonable to expect that the best runners should come from a wide range of countries and racial groups." So why are there such enduring and overwhelming racial differences in the outcome?

Entine is not afraid to say that "genetically linked, highly heritable characteristics, such as skeletal structure, muscle fiber types, reflex capabilities, metabolic efficiency, and lung capacity are not evenly distributed among populations." These traits help to explain why groups succeed--and sometimes fail--in certain sports. For instance, the same body type that works so well in the boxing ring and on the track doesn't do so well in the water. How many black swimmers have there been on the U.S. Olympic team? Even countries on the African coast have a terrible record when it comes to swimming medals.

Entine's book is titled "Taboo" because he knows how controversial his thesis is, how fiercely it is hated and resisted. I suspect this is not because of powerful academic evidence that Entine is wrong. If there is such evidence, I would like to see it, but so far I've had a hard time finding it. Rather, the resistance is due to the liberal fear that if we praise black athletic superiority and attribute it to genes, this opens the door for racists to speculate about black intellectual inferiority and to attribute it too to genes.

Yet this is a non-sequitur. Groups can be unequal physically and still be equal intellectually. Men and women are clearly unequal in upper-body strength, for instance, and yet the average IQ for males and females is the same, although the bell curve distribution of that IQ is not. But I'll leave that subject for a later blog.

My general point is that many liberals are looking in the wrong place to find a justification for their support for political equality. As Jefferson noted a long time ago, inequality of endowment, whether it exists or not, is no warrant for inequality of rights. Equality is not a factual proposition, derived from biology. It is a moral proposition, derived from Christianity.