In "Art Over Biology," literary critic Adam Kirsch questions in The New Republic how the arts can be explained in terms of survival of the fittest:
In his early story “Tonio Kröger,” Thomas Mann created a parable of one of the central modern beliefs, which is that the artist is unfit for life.…Love and marriage and parenthood are barred to Tonio, because he has an artist’s soul….
You may not have been aware that, on average, artists are relatively lacking in sexual opportunities. But just ask artists and they’ll tell you -- maybe over a drink up at their place while they are showing you their etchings -- all about the sacrifices they make for their art. “The artist’s decision to produce spiritual offspring rather than physical ones is thus allied to the monk’s celibacy ...” asserts Kirsch, who evidently hasn’t met many artists (or monks).
Speaking of Thomas Mann's Tonio Kröger, here's L.A. singer-songwriter Tonio K's 1978 single Life in the Foodchain.