Fossils show that howler monkey ancestors, Stirtonia victoriae, were eating leaves 13 million years ago, altering body size ...

From the eerie croak of a tropical frog to the haunting call of the howler monkey, the animal kingdom is filled with some ...

An extinct relative of the howler monkey may have been the first leaf-eating primate in South and Central America ...

Watch a playful howler monkey insist on attention and affection in a funny encounter.

Thirteen million years ago, a group of medium-sized monkeys known for guarding their territory among the treetops with fearsome "howls" started doing something new. These monkeys, among the oldest ...

Key Facts 13.3-million–13.6 million-year-old fossils from an extinct relative of the howler monkey show signs of being the first leaf-eating ...

A playful howler monkey seeks attention and affection, highlighting the gentle and social side of these lively primates.

Recent research indicates a link between an animal’s gut bacteria and brain function. This may be true in humans, too.

Olympic legend Greg Louganis is back in the United States after taking some drastic measures to leave the country. Louganis, ...

In the kitchen of UC Davis Professor Emerita Sarah Blaffer Hrdy, overlooking a long dining table, hangs a painting by artist Isabella Kirkland.

Deep within the tropical rainforests of Central and South America lives one of the most powerful birds on Earth: the harpy ...