title: Costs of and Investment in Mate-Guarding in Wild Long-Tailed Macaques (Macaca fascicularis): Influences of Female Characteristics and Male-Female Social Bonds.
abstract: Male primates living in multimale groups tend to direct mate and mate-guarding choices toward females of high reproductive value, i.e., high-ranking, parous females, or females with which they share strong bonds. Little is known, however, about the constraints that may limit male mate-guarding choices (the costs of this behavior) and the influence of the females' quality on male investment in mate-guarding. We aimed to study the effects of female rank, parity status, and male-female social bond strength on the costs of and investment in mate-guarding by males. We carried out our study during two reproductive seasons on three groups of wild long-tailed macaques in Indonesia. We combined behavioral observations on male locomotion and activity with noninvasive measurements of fecal glucocorticoids (fGC). Males spent less time feeding when mate-guarding nulliparous females than when mate-guarding parous females and tended to have higher fGC levels when mate-guarding low-ranking nulliparous females than when mate-guarding high-ranking nulliparous ones. Evolution should thus favor male choice for high-ranking parous females because such a decision brings benefits at proximate (reduced costs of mate-guarding) and ultimate (higher reproductive value) levels. Further, male investment in mate-guarding was flexible and contingent on female reproductive and social value. Males were more vigilant and more aggressive toward other males when mate-guarding females to which they were strongly bonded and/or high-ranking ones than when mate-guarding other females. Our findings bring a new dimension to the study of mate choice by showing that males not only mate preferentially with high-quality females but may also aim to secure paternity with these females through optimized monopolization.
authors.affiliation: Jr. Research Group Primate Sexual Selection, German Primate Centre, 37077 Göttingen, Germany ; Courant Research Centre Evolution of Social Behaviour, Georg-August University, 37077 Göttingen, Germany.
authors.forename: Cédric
authors.initials: C
authors.lastname: Girard-Buttoz
authors.affiliation: Endocrinology Laboratory, German Primate Centre, 37077 Göttingen, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Heistermann
authors.affiliation: Faculty of Veterinary Medicine, Syiah Kuala University, Banda Aceh, Indonesia.
authors.forename: Erdiansyah
authors.initials: E
authors.lastname: Rahmi
authors.affiliation: Faculty of Veterinary Medicine, Bogor Agricultural University, Bogor, Indonesia.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Agil
authors.affiliation: Faculty of Veterinary Medicine, Bogor Agricultural University, Bogor, Indonesia.
authors.forename: Panji Ahmad
authors.initials: PA
authors.lastname: Fauzan
authors.affiliation: Jr. Research Group Primate Sexual Selection, German Primate Centre, 37077 Göttingen, Germany ; Courant Research Centre Evolution of Social Behaviour, Georg-August University, 37077 Göttingen, Germany.
authors.forename: Antje
authors.initials: A
authors.lastname: Engelhardt
keywords: Feeding costs; Glucocorticoids; Macaca fascicularis; Mate choice; Reproductive effort; Vigilance