Big brain means small testes

This article is depressing.

New Scientist Breaking News - Big brain means small testes, finds bat study: "The brainier male bats are, the smaller their testicles, according to a new study. Researchers suggest the correlation exists because both organs require a lot of energy to grow and maintain, leading individual species to find the optimum balance."

It's another reminder that you can't have it all. Or, as the great science fiction writer Heinlein said, there's no such thing as a free lunch.