It is an interesting read but still fails to explain the dominance of black runners in the sprint and long-distance events.
The high numbers of white competitors in the more technical events, and those that require expensive facilities, is easily explained by the cost and opportunity thing. I’d even buy that the wider the talent pool, the more likely it is that the top athletes will emerge, and that many potential caucasian stars never make it big due to being sidetracked into other careers. What are the other factors?
And to further complicate it, why aren’t more of the 1.4Bn Chinese succeeding in these events? I’d have thought that’s a wide talent pool and that the government would encourage the top competitors to come through with equipment, facilities and coaching.