Does it pay to be a dominant male in a promiscuous species?

• Published in: Annales zoologici fennici Vol. 43; no. 3; pp. 248 - 257
• Main Authors: Klemme, Ines, Eccard, Jana A., Gerlach, Gabriele, Horne, Taina J., Ylönen, Hannu
• Format: Journal Article
• Language: English
• Published: Finnish Zoological and Botanical Publishing Board 2006
• Subjects: Banks; Breeding; Clethrionomys glareolus; Marking behavior; Mating behavior; Mice; Reproductive success; Sexual selection; Social classes; Urine; Voles
• ISSN: 0003-455X; 1797-2450

In many species male dominance leads to an increased access to mates through male-male competition and/or female choice. However, for promiscuous species, in which both males and females mate several times with different partners, male mating success is not necessarily correlated with male reproductive success. We conducted an enclosure study on the promiscuous bank vole (Clethrionomys glareolus) to investigate the influence of male social status on reproductive success. We assessed male dominance in the laboratory from urine marking behavior. Thereafter, we released male pairs of either a clearly different dominance relationship or an equal dominance along with four unrelated females to outdoor enclosures for 10 to 12 days and followed their reproductive output. On average 2.1 females per enclosure were breeding, i.e. the mean operational sex ratio was 1. Paternity analyses revealed no correlation between male dominance and reproductive success. Male body mass, which was not correlated to social status, was also not related to reproductive success. We suggest that, in bank vole males, sexual selection for dominance or body mass may not be strong. The benefit of multi-male mating in promiscuous species may therefore override the benefit of mating with high quality males.