One of my favorite science books ever is Elisabeth Lloyd’s The Case of the Female Orgasm, which does a beautiful job of going case-by-case through postulated adaptive explanations for female orgasms and showing the deficiency of the existing body of work. It’s a beautiful example of the application of rigorous scientific logic; it does not disprove that female orgasms have an adaptive function, but does clearly show that the scientists who have proposed such functions have not done the work necessary to demonstrate that fact, and that some of the explanations are countered by the evidence. Her conclusion was that the likely explanation for the female orgasm was that it wasn’t directly adaptive: women have them because men are selected for having them, and that the women are just along for the happy ride, just as men have nipples because there has been selection for women to have them.
A lot of people detest the book, though. It does rather ruthlessly cut through many adaptive scenarios, and some people just seem to have a bias that if something exists, it must have a purpose. And for some reason, there is an odd preconception that purposeless features are counter to evolution (they aren’t).
Now there’s a new paper out by Zietsch and Santtila that purports to challenge the non-adaptive explanation. It fails. It fails pretty badly, actually. I’ll go further: I thought it was a terrible paper, especially in contrast to the clarity of Lloyd’s work. Here’s the abstract:
