The Black Spider Monkey is rarely seen throughout its habitat in the Amazon rainforest. It has pitch black fur and eyes, four stubby legs, and a long tail. It sleeps high in the tree tops and will jump between trees when gaps are large. It eats leaves, seeds, twigs, and occasionally bird eggs. Females mate every two years from age four onward and give birth after a twenty week gestation period. The Black Spider Monkey has a larger brain than other monkey species.