my top ten list of the most amazing and possibly even true scientific phenomena that blow my mind, continued: the coolidge effect

by nikki meredith

rooster and his henI wonder if anyone will take offense if I propose that when it comes to sex, males have an appetite for novelty.  I’m not sure appetite is the right word when you’re talking about non-human animals but scientists refer to the male predilection for variety as the Coolidge Effect.  A bull, worn out from copulation, shows no interest in the cow he just had his way with.  But bring on a new cow, and he’ll be rarin’ to go. I remember interviewing one researcher who said that, in his experience, the Coolidge Effect in rams is nearly infinite. “As long as you keep supplying the male with new ewes, he’ll keep going until his body wears out.”

I came across the Coolidge effect when I was writing an article for Psychology Today about the differences between the sex lives of gay men and straight men.  At the time, gay men, on average, had vastly more sexual partners so seemed more predisposed to the phenomenon. Heterosexual men were barely holding their own and the theory was that in order to be in relationships with women, men had to tamp down their natural appetite for variety. There’s been a cultural sea change since then and in any case, one needs to be cautious when applying biological principles across species.  The term, however, does have its origins with humans. Some people say the following story is apocryphal.  I prefer to think that it’s not because I love it. Read the rest of this entry »