A marmoset is a tiny monkey, small enough to fit in your hand, that lives in the forests of Central and South America. With their soft fur, expressive faces, and long tails, marmosets look a bit like miniature squirrels that decided to become monkeys. Most species weigh less than a pound when fully grown.

Unlike larger monkeys that swing through trees, marmosets scurry along branches using their sharp claws, almost like squirrels do. They live in family groups and communicate with high-pitched whistles and chirps that sound more like birds than the deep grunts of bigger primates.

Marmosets have an unusual diet: they use their specialized teeth to gouge holes in tree bark, then lick up the sticky sap and gum that oozes out. They also eat insects, fruits, and flowers. In the wild, a marmoset might spend hours clinging to a tree trunk, carefully gnawing tiny holes to reach the sweet sap inside.

These little primates are social and intelligent. Twin babies are common in marmoset families, and the fathers and older siblings help carry and care for the infants, which is rare among primates.