Reproductive success of Bornean orangutan males: scattered in time but clustered in space.

Abstract: The social and mating systems of orangutans, one of our closest relatives, remain poorly understood. Orangutans ( spp) are highly sexually dimorphic and females are philopatric and maintain individual, but overlapping home ranges, whereas males disperse, are non-territorial and wide-ranging, and show bimaturism, with many years between reaching sexual maturity and attaining full secondary sexual characteristics (including cheek pads (flanges) and emitting long calls). We report on 21 assigned paternities, among 35 flanged and 15 unflanged, genotyped male Bornean orangutans (), studied from 2003 to 2018 in Tuanan (Central Kalimantan, Indonesia).