Evolution at a Standstill? I Don’t Buy It.

Reader Howard Covitz sends a link to an interview with Satoshi Kanazawa. I’m not sure I agree with everything he says in the interview, but this is fascinating. And in my opinion, worth pondering.

DC: Evolutionary psychology portrays us as having impulses that took form long ago, in a very pre-modern context (say, 10,000 years ago), and now these impulses are sometimes rather ill-adapted to our contemporary world. For example, in a food-scarce environment, we became programmed to eat whenever we can; now, with food abounding in many parts of the world, this impulse creates the conditions for an obesity epidemic. Given that our world will likely continue changing at a rapid pace, are we doomed to have our impulses constantly playing catch up with our environment, and does that potentially doom us as a species?

SK: In fact, we’re not playing catch up; we’re stuck. For any evolutionary change to take place, the environment has to remain more or less constant for many generations, so that evolution can select the traits that are adaptive and eliminate those that are not. When the environment undergoes rapid change within the space of a generation or two, as it has been for the last couple of millennia, if not more, then evolution can’t happen because nature can’t determine which traits to select and which to eliminate. So they remain at a standstill. Our brain (and the rest of our body) are essentially frozen in time — stuck in the Stone Age.

A few random thoughts:
1. Perhaps evolution selects for ability to adapt, or even luck?
2. Perhaps not everything is changing in unpredictable ways. For example, the need for the ability to use tools, in battle and otherwise, has been a constant for several millenia now. (The cost of this improvement, in terms of food that has to be consumed, may be high though.) Similarly, I can’t think of a single environment in which humans have been in for which being able to see or resist disease better has not been an advantage. (I presume that the “cost” to the body of such adaptations (i.e., the amount of food consumed to maintain such improvements) is minimal.)

Your thoughts.