title: Extra-pair paternity confirmed in wild white-handed gibbons.
abstract: Knowledge of the genetic mating system of animal species is essential for our understanding of the evolution of social systems and individual reproductive strategies. In recent years, genetic methods have uncovered an unexpected diversity of paternal genetic contributions across diverse animal social mating systems, but particularly in pair-living species. In most pair-living birds, for example, genetic and behavioral observations have confirmed a previously unknown significance of extra-pair copulations (EPCs) and extra-pair paternity. Among mammals, white-handed gibbons (Hylobates lar) are also known to live in pairs and are traditionally believed to be single-male single-female breeders. However, at Khao Yai National Park, Thailand, behavioral observations have confirmed the occurrence of both EPCs and functional multi-male grouping, but knowledge about the genetic mating system is still unavailable. In this study, we genotyped 89 white-handed gibbons of the Khao Yai population based on fecal samplings and were able to determine paternity for 41 offspring through short tandem repeat analysis. We found that females' stable social partners sired the majority (90.5%) of offspring (N = 38), while only a few (7.1%) offspring (n = 2 confirmed cases; n = 1 inferred case) were conceived with extra-pair partners. The paternity of one offspring remained inconclusive (2.4%), because the offspring's genotype did not mismatch with the genotypes of two potential sires. Like other predominantly pair-living species, gibbons appear to follow a mixed-reproductive strategy. The genetic mating system of wild white-handed gibbons is best described as flexible, primarily monogamous and opportunistically promiscuous. Inc.
authors.affiliation: Sezione di Biodiversità Tropicale, MUSE-Museo delle Scienze, Trento, Italy; Reproductive Biology Unit, German Primate Center, Leibniz Institute for Primate Research, Göttingen, Germany.
authors.forename: Claudia
authors.initials: C
authors.lastname: Barelli
authors.forename: Kazunari
authors.initials: K
authors.lastname: Matsudaira
authors.forename: Tanja
authors.initials: T
authors.lastname: Wolf
authors.forename: Christian
authors.initials: C
authors.lastname: Roos
authors.forename: Michael
authors.initials: M
authors.lastname: Heistermann
authors.forename: Keith
authors.initials: K
authors.lastname: Hodges
authors.forename: Takafumi
authors.initials: T
authors.lastname: Ishida
authors.forename: Suchinda
authors.initials: S
authors.lastname: Malaivijitnond
authors.forename: Ulrich H
authors.initials: UH
authors.lastname: Reichard
mesh_terms: D000818:Animals; D004272:DNA, Mitochondrial / Q000737:chemistry; D005260:Female; D005838:Genotype; D006922:Hylobates / Q000235:genetics / Q000502:physiology*; D008297:Male; D010152:Pair Bond; D012726:Sexual Behavior, Animal; D013785:Thailand
chemical_list: D004272:DNA, Mitochondrial
keywords: Hylobates lar; genetic paternity; gibbons; monogamy; pair-living; polyandry