Coevett, African athletes dominated the distance during the EPO era because european and American disappeared. In 1991 UK had 9 athletes under 3'32" , and 3 WR holders around 3'30" (Ovett 3'30"77, Cram 3'29"67, Coe 3'29"77), while the best athletes in 2011 was James Shane in 3'36"22. UK had a great tradition in Marathon, with Ron Hill at 2:09 already in 1969, Ian Thompson in 2:09 and European Champion in 1974, and Steve Jones at 2:07:13 in 1985 with a crazy race without pacers that there are today. With all this tradition, in 2003 the best British specialist was a woman, since no men were able to run faster than 2:15:25 !
Blame European that were no longer interested for the African dominance. The reality is that for almost 30 years European disappeared from the scene because THEIR FAULTS, and step by step, since in athletics there is no historical memory, NORMAL performances became something of supernatural, needing doping for reaching them.
When you see in Kenya a Cross Country like Sirikwa, with more than 3000 runners starting from competitions 400m long for children under 5 years, and you compare this to what happen in Europe / America, you understand the real SECRET. It's the ambience, everybody wants to try to run and the best look for a professional career.
Maybe this can push somebody to use shortcuts for emerging, but if you are thousands of fishes and you use a net, many good fish remain in the net. In Europe, we still use the fishing pole, and are not able to find big talents not interested.
The old post about the talent is a real stupidity. Talent is everywhere, the problem is to find it and to create interest about running at top level. In every discipline there is not the prevalence of one people under the potential point of view, but the possibility to find the talent depending of ambience, interest, organization.
We don't have in athletics the category black or white, young or old. We have two categories only : strong and weak, always was like this, and always will be in the future.