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 ...

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

The “big truck, small man” phenomenon is also seen in the animal kingdom. The loudest howler monkeys were found to have the smallest packages. Hyoid bone size, which is responsible for vocalizations, ...

Why are capuchin monkeys kidnapping howler monkey babies in Panama? We investigate this bizarre case of primate abduction with researchers working with the Smithsonian to get to the bottom of this ...

Venezuelan Red Howler (Alouatta seniculus). They inhabit rainforests and mountain forests of Central and South America. The loudest monkey. Morning roar of a red howler. Close-up.© ...