Characteristics of the species:
- With long and slender arms, hoolock gibbons are swift creatures, barely needing to step on the ground. They swing from tree to tree in a mode of locomotion known as Brachiation and can brachiate at speeds up to 55 km/hr., covering up to six meters in just one swing.
- Males and females are of similar size, but can be differentiated easily by the colouration of their dense hair.
- Males are black with a distinctive white brow, while females are copper-tan with dark brown hair on the sides of their face, and a clear central parting in the head hair. They form monogamous pairs that remain together for years, though mating outside the pair has been noticed in some individuals.
- Hoolocks are famous for their emotive call that echoes across long distances in the forest, and is used by individuals to attract mates.
- Females give birth to one offspring every 2-3 years, and it remains within the family group for 7-10 years.
- Food system: Their diet comprises mainly of fruits, but they sometimes also consume leaves, shoots and flowers.