Comparative analysis of long-range calls in equid stallions (Equidae): are acoustic parameters related to social organization?

Abstract

Evolution of long-distance communication in equids may correspond with species-specific types of social organization. To compare harem-forming species (type I) with those that do not establish permanent social units (type II), we conducted a comparative analysis of stallion long-range calls in seven species/breeds of equids: two breeds of domestic horses (archaic and modern breeds) and five wild species: Przewalski’s horse, kiang, Somalian ass, Grevy’s zebra, Grant’s zebra)....