Spider Monkey is found in groups up to 30, which are further broken up into smaller sub-groups of around three or four. It is a very good climber, and has hook-like fingers (no thumb). The tip of the tail can support the weight of whole body. The offspring are dependent on their mothers for the first three years. Females are a little larger and heavier than the males. It eats fruit, leaves, plants, seeds, nuts, grain and insects. Average life span is around 20 to 40 years.