Effect of social system on allosuckling and adoption in zebras

Although nursing non-filial offspring (allonursing) represents costly behaviour to the female, it occurs in a variety of taxa, including ungulates. The only three currently existing species of zebra differ in their ecology and social system. In the wild, mountain zebra Equus zebra and Grevy’s zebra Equus grevyi live in arid environments, while plains zebra Equus quagga inhabit savannahs. Mountain and plains zebra mares form long-term stable herds associated with a social hierarchy, whereas Grevy’s zebra mares form loose associations of short duration. In this study, we investigated the occurrence of allosuckling in three zebra species at the