Onager a subspecies of the onager as "E. hemionus kiang", but recent molecular studies indicate it to be a distinct species, having diverged from the closest relative of the Mongolian wild ass's ancestor less than 500,000 years ago. Widely five recognized subspecies of the onager include: A sixth possible subspecies, the Gobi khulan ("E. h. luteus", also called the "chigetai" or "dziggetai") has been proposed, but may be synonymous with "E. h. hemionus". Debates over the taxonomic identity of the onager occurred until 1980. As of today, four living subspecies and one extinct subspecies of the Asiatic wild ass have been
Pack animal Pack animal A pack animal or beast of burden is an individual or type of working animal used by humans as means of transporting materials by attaching them so their weight bears on the animal's back, in contrast to draft animals which pull loads but do not carry them. Traditional pack animals are diverse including camels, goats, yaks, reindeer, water buffaloes, and llamas as well as the more familiar pack animals like horses, donkeys and mules. The term "pack animal" is traditionally used in contrast to "draft animal", which is a working animal that typically pulls a load behind itself