Orangutans are currently found only in the rainforrests of Borneo and Sumatra. Of all the great apes, orangutans spend the most time in trees. Dominant males develop distinctive cheek pads and produce long calls that attract females and intimidate rivals. They are among the most intelligent of primates, using sophisticated tools and building elaborate nests for sleeping. Primarily, they eat fruit but will also eat vegetation, bark, honey, insects and bird eggs. This orangutan mother and baby sketch depicts the close ties between mothers and their infants.