(Hylobates hoolock), a tailless ape (gibbon) measuring up to 64 cm in length. The fur is long and thick. The young are gray, adult females brown, and males black with white eyebrows. The hoolock inhabits tropical rain forests and mountain forests in Assam, Burma, and western Yunnan. The ape lives in trees, in groups of six to ten individuals. It does not build nests for shelter at night. The diet consists of fruit, leaves, buds, flowers, birds’ eggs, young birds, and insects. A single, almost naked young is produced. Hoolocks attain sexual maturity at seven to ten years of age.