anjohl: If peppers are hot as an evolutionary adaptation to mammals (Due to our being poor seed-couriers due to range limitations vs. birds, which are immune to capacsin as an evolutionary result), but we SEEK OUT hotter peppers, wouldn't that mean that eventually peppers will get LESS hot due to the hottest kinds being desired by humans?
captfitz: no, because the ones we eat are cultivated. they will only get hotter because we determine whether they are replanted or not, so we will replant the ones we like best, which are hot.
He is referring to our capsaicin receptors. Obviously the amount in the peppers will not change, but our reaction to capsaicin may. However, as you mention, we cultivate hotter peppers.
As such, if any evolution/adaptation will occur, it is likely that peppers, as a whole, will be "less hot" as far as we are concerned, with a select few super-peppers that are "freaky hot" as far as we are concerned.