I saw this guys Ted Talk and it wasn't very appealing, just two many facts. Perhaps some highlights are good to put running in a historical perspective. Seems that Jesse Owens wasn't slow at all. Since his time the track, shoes and what not have allowed times to get shorter thanks to reducing friction. In the top ten of a race with Usain Bolt he wouldn't come last, but rather second, and that is just numbers. Maybe if he were here he'd come first. Who knows?
Perhaps reading Epstein's epilogue can put in perspective the nature vs nurture conversation. Running with the Kenyans already does a bit of that. The more the merrier.