The Sumatran orangutan (Pongo abelii) is an ape that inhabits the tropical rainforests of Sumatra and lives primarily in the trees. Body length is 1.3–1.8 m and body weight is 30–90 kg, with males about twice the size of females. Fruit is the main food, and they also use tools to obtain insects and honey. Individuals are generally solitary, but in Sumatra they sometimes move about in relatively larger groups; culturally transmitted tool use and a variety of kiss-squeak vocalizations have been reported. Breeding is concentrated in the rainy season, and they are characterized by long parental care and long intervals between births. Conservation status: Critically Endangered (IUCN Red List: Critically Endangered, category 1A).