Males and females gain differentially from sociality in a promiscuous fruit bat Cynopterus sphinx

PLoS One. 2015 Mar 20;10(3):e0122180. doi: 10.1371/journal.pone.0122180. eCollection 2015.

Abstract

Sociality emerges when the benefits of group living outweigh its costs. While both males and females are capable of strong social ties, the evolutionary drivers for sociality and the benefits accrued maybe different for each sex. In this study, we investigate the differential reproductive success benefits of group membership that males and females might obtain in the promiscuous fruit bat Cynopterus sphinx. Individuals of this species live in flexible social groups called colonies. These colonies are labile and there is high turnover of individuals. However, colony males sire more offspring within the colony suggesting that being part of a colony may result in reproductive benefits for males. This also raises the possibility that long-term loyalty towards the colony may confer additional advantage in terms of higher reproductive success. We used ten seasons of genetic parentage data to estimate reproductive success and relatedness of individuals in the colony. We used recapture data to identify long and short-term residents in the colony as well as to obtain rates of recapture for males and females. Our results reveal that males have a significantly higher chance of becoming long-term residents (than females), and these long-term resident males gain twice the reproductive success compared to short-term resident males. We also observed that long-term resident females are related to each other and also achieve higher reproductive success than short-term resident females. In contrast, long-term resident males do not differ from short-term resident males in their levels of relatedness. Our results re-iterate the benefits of sociality even in species that are promiscuous and socially labile and possible benefits of maintaining a colony.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Chiroptera / physiology*
  • Female
  • Male
  • Reproduction
  • Seasons
  • Sexual Behavior, Animal*
  • Social Behavior*

Grant support

This work was supported by Department of Science and Technology grant to UR, National Centre for Biological Science-Tata Institute of Fundamental Research funding to KMG and UR, and Department of Science and Technology Young Scientist grant to DPS. UR was supported by the Ramanujan fellowship (Department of Science and Technology, Government of India). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.