History of the domestic sheep exact line of descent between domestic sheep and their wild ancestors is unclear. The most common hypothesis states that "Ovis aries" is descended from the Asiatic ("O. orientalis") species of mouflon. A few breeds of sheep, such as the Castlemilk Moorit from Scotland, were formed through crossbreeding with wild European mouflon. The urial ("O. vignei") was once thought to have been a forebear of domestic sheep, as they occasionally interbreed with mouflon in the Iranian part of their range. However, the urial, argali ("O. ammon"), and snow sheep ("O. nivicola") have a different number of chromosomes than other Ovis species,
Wild Bactrian camel domesticated Bactrian camel, it is one of the few mammals able to eat snow to provide itself with liquids in the winter. While the legend that camels store water in their stomachs is a misconception, they cannot survive without water for long periods but do have the capacity to conserve water. Wild Bactrian camels ("Camelus ferus") appear similar to Bactrian camels ("Camelus bactrianus") but the outstanding difference is genetic, with the two species having descended from two distinct ancestors. There are several differences in size and shape between the two species. The wild Bactrian camel is slightly smaller than the