Abstract
Aim Within the last several decades, G révy's zebra ( E quus grevyi ) has undergone a massive reduction in geographical range and population size, largely as the result of human impacts. To place its recent decline in a deeper prehistoric context, and to understand the factors mediating its range and abundance over geological time frames, this study examines the fossil history of G révy's zebra in equatorial E ast A frica. Location Equatorial E ast A frica. Methods Presence/absence data for ungulates recovered from fossil sites spanning the last c . 400,000 years in K enya and E thiopia were compiled from the literature and from previously unreported palaeontological sites. Associations between G révy's zebra and other taxa were examined using principal coordinates analysis and non‐random species pairs were identified using a Bayesian approach. Changes in rainfall were reconstructed using the average hypsodonty index of ungulate species from fossil assemblages. Results G révy's zebra was common during dry phases of the P leistocene and was found to the south and west of its historical range, coinciding with an expansion of arid grasslands. At the onset of the H olocene, G révy's zebra was extirpated from southern K enya and almost completely disappeared from the fossil record. G révy's zebra was associated with several specialized grazers that became extinct by the end of the Pleistocene. These extinctions and the decline of G révy's zebra from the P leistocene to the H olocene are explained by increased precipitation and the consequent loss of arid grasslands at the P leistocene– H olocene transition. G révy's zebra is never associated with domestic livestock, unlike the widespread plains zebra. Main conclusions Grévy's zebra thrived in equatorial E ast A frica during periods of the P leistocene when environmental conditions favoured an expansion of arid grasslands. Environmental change across the P leistocene– H olocene transition contributed to decreases in the range size and abundance of G révy's zebra, setting the stage for the anthropogenic decline observed in recent decades. The spread of pastoralists in the middle H olocene may have additionally contributed to its prehistoric decline. Contemporary climate change warrants further consideration in planning for the long‐term survival of G révy's zebra.