Our ancestors survived through a bias for action (e.g. eating every scrap of food I can get my hands on or clubbing a creature that looks at me sideways) not a bias for planning (thinking about retirement from hunting and gathering).
It is this ethical commitment to rigor that distinguishes philosophy (at least in its analytical form) from science, which has begun facing a veritable inquisition, both in the academic and popular press, for sloppy thinking, cherry picking data, systemic bias and, in some cases, outright fraud.
Confirmation bias is a type of selective thinking in which we tend to notice and look for that which confirms our beliefs and positions, and to ignore or undervalue the relevance of anything that is contradictory.