- Henry Park
I recall in a college biology course reading about how moth populations in the UK changed depending on the amount of pollution. When there was more pollution, there was an abundance of dark-colored moths. And, when there was less pollution, there were more light-colored moths (see Wikipedia article).
I found this dark-colored moth in Switzerland. You don't see many dark-colored moths around. I wonder if the rarity of dark-colored moths stems from the same evolutionary pressure.