Here's a way to think about this: suppose it _were_ true that "all people have natural talents" - what are some mechanisms that would be at work that insure that fact is always true for everyone? if you can't think of how that would work, that's a strike against the hypothesis, no? 

 The whole development process up to birth. If your DNA is too dysfunctional, you don't make the cut. Even the lowest human has qualified to live as a human.