The wild population was already rare at the time of its first scientific characterization. Przewalski reported seeing them only from a distance and may actually have instead sighted herds of local Mongolian asses, and he was only able to obtain the type specimen from Kirghiz hunters. The range of Przewalski's horse was limited to the arid Dzungarian Basin in the Gobi Desert. It has been suggested that this was not their natural habitat, but that instead they were like the local populations of onager, a steppe animal driven to this inhospitable last refuge by the dual pressures of hunting and habitat loss to agricultural grazing. There were two distinct populations recognized by local Mongolians, a lighter steppe variety and a darker mountain one, and this distinction is seen in early twentieth-century descriptions. Their mountainous habitat included the "Takhiin Shar Nuruu" (The Yellow Wild-Horse Mountain Range). In their last decades in the wild, the remnant population was limited to the small region between the Takhiin Shar Nuruu and Bajtag-Bogdo mountain ridges.