Brilliant...
I don't know. Some of these things seem obvious. But that's always easy to say in hindsight. (The same is true of natural selection.) One test of this is to see if it's geographically true. I assume that's already the situation. So we have no counter-examples. Still, although it seems to explain a lot, I don't know where we go with this. But it's interesting.
I'm concerned that this could give a lot of ammo to environmentalists.