Genetics of Equid Species and Subspecies

During the Pleistocene, numerous species of equids were found in North and South America, Asia, and Africa. Of these, only seven or eight species remain today (depending on whether the domestic and Przewalski’s horse are counted as one or two species). Although the fossil record of Equidae is one of the classic examples of the evolutionary process, there are still many aspects of the evolution and the relationships of both extinct and extant equids that remain unclear. Understanding the relationships and genetic distinctiveness of populations, subspecies, and species is both of academic interest and of importance to conservation management. Resources for conservation are limited and it is in this context that we need to determine the conservation priorities. Should we attempt to conserve all populations and subspecies, or would it be better to direct our efforts to saving representatives of each species? This question can only be answered by determining what is required to ensure the preservation of the evolutionary heritage of the genus and thus protect its evolutionary potential. In short, we need to know what are the evolutionary significant populations for equids (Ryder 1986; Moritz 1994; Crandall et al. 2000), the answer to which may be found through further genetic studies along with ecological information (morphological, behavioural, habitat).