Overcompensating? Howler monkeys with loudest mating calls have smallest testicles

The GLP aggregated and excerpted this blog/article to reflect the diversity of news, opinion and analysis. 

Howler monkeys are the loudest land animals on Earth, capable of bellowing at volumes of 140 decibels, which is on the level of gunshots or firecrackers. Not surprisingly, male howlers frequently use this power to advertise their sexual fitness, catcalling females with their ear-splitting roars.

But in a beautiful twist of expectations, scientists have now found that the louder the monkey’s calls, the smaller the monkey’s balls. A team based out of Cambridge University came to this conclusion by comparing the size of dozens of monkeys’ testes with the hyoid bones located in their voice boxes, which revealed a negative correlation between decibel levels and testicular endowment. The results are published in the journal Current Biology.

Naturally, Knapp warns against anthropomorphizing these findings, and she is completely right. There is a world of difference between howler monkeys and humans, especially with regard to sexual selection.

And yet, the study still conjures up visions of dudes who ride incomprehensibly loud motorcycles, or who catcall women on the street. Far from coming off as masculine, this kind of thing reeks of overcompensation in other, more sensitive areas. As the saying goes: the empty vessel makes the loudest sound, and it seems that may be especially true when the vessel in question is balls.

Read full, original post: The Louder the Monkey, the Smaller Its Balls, Study Finds

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