Male mating effort and female preference in relation to male dominance rank, tenure length, and age in wild vervet monkeys.

In this study, we aimed to evaluate the effect of male dominance rank, tenure, and age on male mating effort and female choice while quantifying four sociometric variables of male dominance hierarchy (stability, linearity, directional consistency, steepness) in two groups of wild vervet monkeys (Chlorocebus pygerythrus) at Lewa-Borana Conservancy, Kenya. We collected a total of 305 hours of behavioural data across a 4-month field season in 2022 on 13 adult/subadult males. Overall, adult, high-ranking males who had been in the group for a shorter amount of time, generally put forth more mating effort, copulated more frequently, and were preferred by females. The male dominance hierarchies for both groups were stable (mean S = 0.9844 ± 0.001), quasi-linear (mean h’ = 0.7554 ± 0.018), unidirectional (mean DCI = 0.7017 ± 0.121), and moderately steep (mean Dij = 0.6437 ± 0.044).