Intergroup contests determine access to
resources and influence the evolution of group living in social
species. Asymmetries in resource holding potential and payoffs should
influence the outcome and intensity of such contests. We evaluated
predictors of contest outcome and intensity using data collected over
40 months from 6 groups of wild blue monkeys (Cercopithecus mitis). We
found increased odds of winning when a group was larger than and used
the contest site more than its opponent, and when contests occurred
closer to its home range center while further from the opponent’s
center. Across five pairs of opponent groups, however, there was no
relationship between the average difference in group size and the
proportion of contests won by the larger group. Some evidence suggested
increased odds of a draw when group sizes were more similar and when
contests occurred closer to one group’s home range center. Contests
were more aggressive when group size and use of the contest site were
more similar and when the contest site was similarly central/peripheral
in both groups’ home ranges. Contests were also longer when located in
this way, but contest duration increased with larger group size
asymmetry. Overall, both resource holding potential and location-based
payoff asymmetries influenced a group’s competitive advantage as well
as the intensity of intergroup contests. Location-based payoff
asymmetries were more consistent, however, in predicting the winner of
such contests.
Publications from MA work:
Roth, A.M., Cords,
M. 2016. Effects of group size and contest location on the outcome
and intensity of intergroup contests in wild blue monkeys. Animal Behaviour 113:49-58. doi:10.1016/j.anbehav.2015.11.011
Roth, A.M., Cords,
M. 2015. Some nocturnal and crepuscular mammals of Kakamega Forest: photographic evidence. Journal of East African Natural History 104: 213-225. doi: http://dx.doi.org/01.2982/028.104.0114
After graduation, Allison moved to Oxford University for her PhD.