Darwin explained the extravagant beauty of some birds, fish and insects as providing an advantage in attracting mates. He called it sexual selection, and he was pretty clear that the process was different from acquisition of traits that had practical use in an objective sense. Female preferences co-evolve with male coloration.
It is hard to escape the conclusion that there is something wonderful here that transcends the quest for mating success. Why is it that the peacock’s aesthetics or the butterfly’s taste for color should resonate so well with our human perceptions of what is beautiful?
This NYTimes Mag article flirts with the idea that beauty is not entirely explained by evolutionary science.
What we call beauty is not simply one thing or another, neither wholly purposeful nor entirely random, neither merely a property nor a feeling. Beauty is a dialogue between perceiver and perceived. Beauty is the world’s answer to the audacity of a flower. It is the way a bee spills across the lip of a yawning buttercup; it is the care with which a satin bowerbird selects a hibiscus bloom; it is the impulse to recreate water lilies with oil and canvas; it is the need to place roses on a grave.