Yellow-cheeked gibbon

The yellow-cheeked gibbon is a species of gibbon native to Vietnam, Laos, and Cambodia. The yellow-cheeked gibbon is born blond and later turns black. Males carry this colouring through their lifespan and have the distinguishing golden cheeks. Females are born blonde to blend into their mother's fur but they later turn black. Females turn back to blond at sexual maturity, keeping only a black cap on the top of their heads