Squirrel monkey fur is short and close, colored olive at the shoulders and yellowish orange on its back and extremities. Their throat and the ears are white and their mouths are black. The upper part of their head is hairy. This black and white face gives them their German name,"skull monkeys".

Spider monkeys are diurnal and spend the night in carefully selected sleeping trees. Groups are thought to be directed by a lead female who is responsible for planning an efficient route for the day's feeding activities. Grooming is not as important to social interaction, due perhaps to a lack of thumbs.

Capuchin monkeys are the most intelligent and adaptable of all the South American primates. They have the largest brain-to-body ratio of any non-human primates and they are one of only a few animals, apart from man, to construct and use tools.The flexible diet and adaptable lifestyle of the capuchins has enabled them to extract food from sources no other animals can get to and this has made it possible for capuchins to co-exist side by side with other primates with similar diets.

Red howler monkeys live in relatively large social groups, consisting of approximately 10 individuals, with only one or perhaps two of the individuals being males. They are most famous for their "dawn chorus", a deafening roar that can be heard up to 5 kilometers away! These resonating howls, performed primarily by the males of a group, are answered by all other howler troops within ear shot. This way, one troop can constantly inform another of its precise location, thus avoiding an energetically costly squabble over resources.