
Originally Posted by
BritNick
Well that's just plain blinkered. You are suggesting that every being is born as a blank canvass with identical innate ability? Then how do you account for the incredible variety in the world? How do you account for race horses' selective breeding to produce the winners? There is quite a variation in their race times too, and I would suggest they would be less subject to the environmental variations and vagaries that humans bring upon themselves.
Genetic variations (mutations) enabled some humans to survive the plague. Similar variations give some low natural heart rates, high VO2max, low lactate production, etc. (Lance Armstrong is a case in point).