Hooting howler monkeys of the species Alouatta caraya make a racket. Howler monkey calls are as deep as those of much larger animals like tigers — a talent enabled by their enlarged hyoid bones.

Northern muriquis, which live in the Atlantic forest of Brazil, are one of the most endangered species of monkey in the world. To better understand what goes on in the mating lives of muriquis, ...

Video: The ejaculation-inducing cries of promiscuous female macaques during sex arouse other local males – perhaps to increase her chances of multiple matings There’s something kinky going on in the ...

Northern muriquis, which live in the Atlantic forest of Brazil, are one of the most endangered species of monkey in the world. Choosing good mates and rearing thriving offspring are key to the species ...

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 ...