People have their own thoughts on evolution, but does evolution also apply to their thoughts? I don't mean the evolution of culture and ideas since the dawn of history (or before that, which is the subject of evolutionary psychology). I mean within a single person whose subjective awareness forms their reality. In that one person, when thoughts arise to the fore of the mind, what forces affect them and determine their fate? Will they be forgotten? Remembered? How, why, and what are the possible implications? Consciousness is only a small fraction of what our brain does, and a very fragile fraction at that.
Last night I was nodding off to sleep as my daughter was reading me a bedtime story. I had a thought, and considered writing it down but sleep overtook me. When I awoke it was gone - another species of thought extinguished through the merciless action of natural selection within the confines of my mind. Most animal species go extinct without leaving descendants, so too I imagine must thoughts.