Baby, I'm howlin' for you. Male howler monkeys make deep and boisterous calls to attract mates, but the deepest-pitched songs may come at cost: the size of their testicles. A new study in the journal ...

Howler monkeys are named for their impressive howling roars. Their vocal abilities are linked to long vocal folds and a hyoid bone uniquely adapted to resonate sound, making males seem bigger than ...

WASHINGTON (Reuters) - The howler monkeys whose guttural calls reverberate through Central and South American rainforests possess a secret that the males of the species may prefer to be left ...

SALT LAKE CITY, Oct. 22, 2015 - Across the animal kingdom, males hoot and holler to attract females and ward off competing suitors. Now, a new study finds that male howler monkeys with deeper calls ...

Add Yahoo as a preferred source to see more of our stories on Google. Venezuelan Red Howler (Alouatta seniculus). They inhabit rainforests and mountain forests of Central and South America. The ...

Quiet on the tee? The howler monkeys weren’t having it. Hidden in the canopy above me, the loudest mammals on the planet were holding forth in full-throated violation of golf etiquette: primates with ...

A black howler monkey vocal chorus is seen at the Biological Field Station Corrientes, Argentina in this handout image released to Reuters on October 21, 2015. REUTERS/Mariana Rano/Handout via Reuters ...