Thank you for visiting nature. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser or turn off compatibility mode in Internet Explorer.
In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript. In many animal societies, a small proportion of dominant females monopolize reproduction by actively suppressing subordinates. Theory assumes that this is because subordinate reproduction depresses the fitness of dominants, yet the effect of subordinate reproduction on dominant behaviour and reproductive success has never been directly assessed.
Here, we describe the consequences of experimentally preventing subordinate breeding in 12 groups of wild meerkats Suricata suricatta for three breeding attempts, using contraceptive injections. When subordinate breeding is suppressed, dominants also show improved foraging efficiency, gain more weight during pregnancy and produce heavier pups, which grow faster.
These results confirm the benefits of suppression to dominants, and help explain the evolution of singular breeding in vertebrate societies. Understanding the evolutionary paradox of eusociality requires that we explain the origins of extreme reproductive inequality within stable societies 1 , 2 , 3 , 4.
Research has been dominated by theoretical models, often with limited empirical support 5 , 6 , 7 , 8 , 9. A principal assumption has been that group-living females compete over the resources required to breed, and that dominants benefit from the reproductive inactivity of subordinates 2 , 6 , Conflict is expected to be particularly acute in cooperative breeders, where non-breeding subordinates usually contribute to offspring care.
