The pygmy marmoset is a small New World monkey native to rainforests of the western Amazon Basin in South America. It is notable for being the smallest monkey and one of the smallest primates in the world at just over 100 grams.

Both male and female pygmy marmosets are orange-brown. Each hair has stripes of brown and black, called agouti coloring. This coloration gives them good camouflage. A mane of hair covers the pygmy marmoset’s ears. Most primates have flat nails on the ends of their fingers, along with opposable thumbs that allow them to grasp objects. Pygmy marmoset fingernails are like claws to help them climb up and down tree trunks and they do not have opposable thumbs. The tail is not prehensile, but it helps the little monkey keep its balance as it gallops through the treetops.

A mother pygmy marmoset’s gestation period is about 4.5 months, and she can give birth every 5 to 7 months. She almost always has two babies. Each newborn is about the size of a human thumb! Pygmy marmosets communicate with each other by chattering and trilling in high-pitched voices. They can make sounds so high in pitch that humans can’t hear them.

The National Zoo & Aquarium is home to 2 Pygmy Marmosets: Sofia and Adora