Thursday, December 4, 2008

Smart Sperm

A new paper suggests that general intelligence reflects genetic fitness. I couldn't access the paper so I'm relying on The Economist report.

The authors argue that intellectual ability, in its established demonstrations (the Economist article mentions artistic and musical ability), has been accentuated by sexual selection as a peacock's plumage or a lion's mane or a bird's mating dance are thought to have been. The authors document a correlation between sperm health and intelligence found retrospectively in military volunteer studies. They offer this as evidence for intelligence as one part of general genetic fitness.

The Economist suggests that the politically correct crowd will object to the paper, though I'm not sure about that. Do politically correct people object to a genetic basis for intelligence? Perhaps some, but the larger concern of political and actual correctness seems to be assumptions of genetic intelligence differences between groups, for which there is no evidence. (By the way, genetic differences are consistently shown larger within groups than across them). It is easy, however, to imagine other objections to the paper - the slippery definition of intelligence and credibility of cognitive exams come to mind. Not to mention the complexities of sexual interactions. From the abstract, it seems the authors are arguing for intelligence as part of a general fitness factor. It's interesting research but the implications don't strike me as particularly profound.

If the paper doesn't offend the politically correct, it may offend fans of the Revenge of the Nerds movies as the paper fundamentally undermines the films' premise. Then again, I think the nerd does get the girl in the movie. Once again, the Revenge of the Nerds has proven resistant to any intellectual criticism.

(illustration by Peter Schrank, economist.com)