This tamarin species has a long sagittal crest, white hairs from forehead to nape flowing over the shoulders (“Cottontop”). The back is brown, and the underparts, arms and legs are whitish-yellow. Rump and inner thighs are reddish-orange.
It is considered one of the bare-faced tamarins because of the lack of facial hair. Its lower canine teeth are longer than its incisors, so it seems as if it has small tusks. It is about the size of a squirrel and weighs 10-18 ounces. The males are only slightly larger than females. A medium Cottontop Tamarin weighs 432 g.Tamarins are among the smallest of the primates.
It moves from tree to tree by running or walking quadrupedally along horizontal branches and leaping as much as three meters between branches. It moves with quick, jerky movements. It is very alert and active. Claw-like nails help it to grip branches, since its small size and non-opposable fingers make encircling difficult. Long limbs and a long tail make it suited for jumping.
Its diet largely consists of insects, ripe fruit, seeds, nectar, and gum from trees that has oozed out. Other foods include some tender vegetation, spiders, small vertebrates, and bird’s eggs. Mice, frogs, birds and lizards are skillfully killed by a quick head bite, a learned behavior.
Up to the 1980s, the Cottontop Tamarin was thought to occur from Costa Rica south to northern Colombia. By 1992 it could be found only in northern Colombia. Significant exports for biomedical research contributed to the Cottontop Tamarin’s decline in the late 1960s and early 1970s. Currently, deforestation is the greatest threat.
Life span in captivity has been as high as 25 years whereas life span in the wild is about 13–16 years. The population is less than 1000 in the wild and about 1800 in captivity, and is continuing to decline. This species is endangered, having lost three-quarters of its original habitat to deforestation. Clearing of forest habitat by people is the main problem and populations also were depleted by taking them for the pet trade and for scientific research. They are now protected by international law, although they are numerous in captivity, they are still critically endangered in the wild.