The Squirrel monkey body length reaches 25-36 cm, the tail – up to 40 cm. Body weight – up to 1.1 kg. The hairline is short, the skin is in the area of the front part of the muzzle, the lips and the patch near the nostrils are practically hairless, black. The front part in the eye area, as well as the ears, throat and sides of the neck are white. Pregnancy lasts 168-180 days, most often there is one cub. Individuals live on average 6-8 years, in captivity – up to 9 years and more. There is a case where the female lived for 21 years.
Habitat – tropical forests of South America, to the south reach Peru, Bolivia, Paraguay, except the highlands of the Andes. They settle near reservoirs in groups of 10 to 100 individuals, sometimes more.
Squirrel monkeys all day in constant movement, and spend the night at the tops of palm trees, which serve them as the most faithful refuge. They are very timid, they dare not move at night, they turn into flight at the slightest danger, and then you can see how the whole herd drags along a long string of tree tops. Ahead is the leader, who, thanks to the agility of these animals, soon leads the whole herd to a safe place.
All movements of squirrel monkey are surprisingly graceful. They excellently climb and jump with amazing ease quite large spaces. In rest, the position of a sitting dog is often accepted; during sleep, they lower their head between the legs, so that it touches the ground. The tail serves them mostly as a rudder during jumps.
True, they sometimes wrap an object around them, but they can not restrain their tail. Their voice consists of a whistle repeated several times. When something unpleasant happens to them, they start screaming and squealing. In the morning and in the evening, such cries of a whole society are heard often, and even at night screeches are heard screeching animals and awakens in the forest a fallen asleep life.
They feed on with insects, fruits, nuts, and also eat eggs of birds and chicks. Sometimes the diet includes shellfish and small frogs.