evolution and speculation
i was watching my cats fight this morning (nothing bad, don't worry, no kitties harmed in this observation) and noticed the flattening of their ears like all kitties do when they are fighting. I suspect that some evolutionary biologist would be able to say "why" they do this, i.e., provides a lower profile for hitting, makes them look meaner, etc.
My point is that just because someone provides an explanation for something and attributes it to evolution doesn't mean that is why somethign is occuring. for one thing, we don't know why a cat does that as we have no access to a cat's conscious awareness. we can infer reasons why, but that is all they are...inferences.
Second is that evolution has not stopped. What we could be witnessing in any behavior is a behavior that is not selected for, but is dying out; we just haven't been around long enough to notice it dying out. For that matter, I suspect that one could argue that all behavior is/was adapative at one time, hence it's existence. Granted, some could have been produced by mutation and serve no advantage, but within any one person's lifetime, we would not know this.