White-handed gibbons (Hylobates lar) are small, agile apes known for their long arms and acrobatic movement through the treetops. They have a lightweight frame, with fur that can range from pale beige to dark brown or black. Regardless of coloration, they all feature distinctive white fur on their hands, feet, and a white ring encircling their dark face. As tailless primates, their upright posture and long arms are specially adapted for brachiation, allowing them to swing swiftly from branch to branch. Socially, white-handed gibbons are monogamous and live in small, close-knit family groups consisting of a bonded pair and their offspring. They are highly territorial and use complex, loud vocalizations—often duets between mates—to communicate and defend their territory. Reproduction can occur year-round, with a single infant born after a gestation period of about seven months. The young are cared for primarily by the mother, staying close to her for several years before leaving to form their own family group.