Orang utans feed primarily on forest fruits, including durians, jackfruits, lychees, mangos, and figs. Leaves and shoots make up the remainder of their diet, supplemented occasionally by small animals, tree bark, and soils rich in minerals. Researchers have documented more than 400 different foods eaten by wild orang utans. Male orang utans establish home ranges that embrace those of several females. Females reach maturity at around ten years of age and can remain fertile for more than 30 years.
Recent research suggests that, on average, wild females give birth only every eight years.
Young orang utans may nurse until age six, and stay close to their mothers until the next offspring comes along. Orang utans may live about 35 years in the wild, and up to 60 in zoos. Active during the day, orang utans spend much of their lives high in the trees. Solitary, they rarely encounter others of their kind unless sharing a fruiting tree or mating. Each night, orang utans bend branches into nest platforms that support the apes while they sleep in the trees.