Department of Anthropology, University of Texas at Austin
April 16, 2016 , Atrium Ballroom A/B
In many non-human primates living in multimale groups, male reproductive success is usually skewed towards dominant individuals. Models of reproductive skew predict that female monopolization by males depends on the number of receptive females that can be monitored by the dominant male and the number of males in the group that might constitute competitors for access to females. However, female reproductive strategies might hinder dominant males’ monopolization of matings by providing reproductive opportunities to non-dominant and extra-group males. We explored male reproductive skew in a population of Verreaux’s sifaka (Propithecus verreauxi) living in Kirindy Mitea National Park, Madagascar. Using an array of 14 microsatellite markers, we analyzed maternity and paternity for 32 individuals born in five social groups between 2007 and 2012. Out of 27 offspring whose paternity was successfully assigned, 85% were born to either the sole resident male in single-male groups or to the dominant resident male in multimale groups. Dominant males in multimale groups sired 71% of offspring, however, this result was not significantly different from an even distribution of paternities among dominant and subordinates. Male reproductive skew was also not significantly biased towards males with longer tenure. Although dominant males in multimale groups were unable to completely monopolize female matings, subordinates’ reproductive success did not increase when more females were present in the group. Our study suggests that in this female-dominant species, female choice may play an important role in paternity distribution because intersexual dominance relationships may prevent males from monopolizing female reproduction entirely.
Supported by the L.S.B. Leakey Foundation and the University of Texas at Austin