scientific testicles

The Louder the Catcall, the Smaller the Balls

Awooooga. Photo: Mark Bowler/Corbis

Catcalling, also known as street harassment, has been a hot topic around the watercooler the past few years — one of the many, many subjects on which women have the right to express discontent. But despite its negative connotation in the lexicon, “catcalling” hasn’t let up just because la blogs were talking about it. Perhaps a little science could help move it out the door?

A new study published in Current Biology has revealed a correlation between the volume capacity of male howler monkeys and their sperm count. Jacob Dunn, lead researcher from the University of Cambridge’s Division of Biological Anthropology, found in his research that howler monkeys, who rank as one of the loudest animals on the planet, have smaller testicles when they develop larger vocal organs, the tool they use to attract female monkeys by howling loudly in their direction. Plainly speaking, they spend their energy on the chase, but potentially can’t perform in the catch. In science language, there is an “evolutionary trade-off between investment in precopulatory vocal characteristics and postcopulatory sperm production,” according to Dunn. “When males invest in large bodies, bright colors, or weaponry such as horns or long canines, they are unable to also invest in reproductive traits.” Hey, sounds familiar.

Perchance this science is applicable across the mammal class? Dunn seems to suggest it might be: “In evolutionary terms, all males strive to have as many offspring as they can, but when it comes to reproduction you can’t have everything,” he says in the study. No kidding. Science is great.

The Louder the Catcall, the Smaller the Balls