Why would we have these modules that seem quite complex, and likely to negatively effect fitness (thinking’s expensive), if they don’t do anything? What are the odds of this becoming a prevalent without a favourable selection pressure?
Sometimes you get spandrels, and sometimes you get systems built on foundations that are no longer what we would call “adaptive”, but that can’t be removed without crashing systems that are adaptive.
Here’s one: it turns out that ascribing consistent identity to nominal entities is a side-effect of one of the most easily constructed implementations of “predict the behavior of my environment.” Predicting the behavior of my environment is enormously useful, so the first mutant to construct this implementation had a huge advantage. Pretty soon everyone was doing it, and competing for who could do it best, and we had foreclosed the evolutionary paths that allowed environmental prediction without identity-ascribing. So the selection pressure for environmental prediction also produced (as an incidental side-effect) selection pressure for identity-ascribing, despite the identity-ascribing itself being basically useless, and here we are.
I have no idea if that story is true or not; I’m not sure what I’d expect to see differentially were it true or false. My point is more that I’m skeptical of “why would our brains do this if it weren’t a useful thing to do?” as a reason for believing that everything my brain does is useful.
Why would we have these modules that seem quite complex, and likely to negatively effect fitness (thinking’s expensive), if they don’t do anything? What are the odds of this becoming a prevalent without a favourable selection pressure?
High, if they happen to be foundational.
Sometimes you get spandrels, and sometimes you get systems built on foundations that are no longer what we would call “adaptive”, but that can’t be removed without crashing systems that are adaptive.
Evo-psych just-so stories are cheap.
Here’s one: it turns out that ascribing consistent identity to nominal entities is a side-effect of one of the most easily constructed implementations of “predict the behavior of my environment.” Predicting the behavior of my environment is enormously useful, so the first mutant to construct this implementation had a huge advantage. Pretty soon everyone was doing it, and competing for who could do it best, and we had foreclosed the evolutionary paths that allowed environmental prediction without identity-ascribing. So the selection pressure for environmental prediction also produced (as an incidental side-effect) selection pressure for identity-ascribing, despite the identity-ascribing itself being basically useless, and here we are.
I have no idea if that story is true or not; I’m not sure what I’d expect to see differentially were it true or false. My point is more that I’m skeptical of “why would our brains do this if it weren’t a useful thing to do?” as a reason for believing that everything my brain does is useful.