They also use their hands to grasp small twigs that they can use as a tool to obtain food and hold food in their hands while they move about. Males are about twice as big as females and have striking flaps on their cheeks. They can make very strong calls by inflating a pouch in their throat, which adds resonance to their call. Orangutans have large brains and exhibit a high level of intelligence. Orangutans can eat a large amount of food.
Orangutans live in humid jungles of Borneo and Sumatra.
They spend most of the time in the trees, but occasionally move down to the ground. Adults are live in solitude, occasionally pairing up during mating season. The territory of an adult is not exclusive, but instead frequently overlaps the territory of other adults. When several adults meet for a single food source, they often eat and leave without any social interaction. Males keep track of each other by giving loud calls.