Mouflon scientific literature as separate species, "Ovis musimon" and "Ovis orientalis". The mouflons are also sometimes treated as a subspecies of the domestic sheep, "Ovis aries", named with the same subspecific epithet as above: "O. a. musimon", "O. a. ophion", etc. Based on comparison of mitochondrial cytochrome b gene sequences, three groups of sheep ("Ovis") have been identified: Pachyceriforms of Siberia (snow sheep) and North America (bighorn and Dall sheep), Argaliforms (argali) of Central Asia, and Moufloniforms (urial, mouflon, and domestic sheep) of Eurasia. However, a comparison of the mitochondrial DNA control region (CR) found that two subspecies of urial, "Ovis
Wild horse taxonomists considered domesticated and wild horse two subspecies of the same species, the valid scientific name was "Equus caballus" Linnaeus 1758, with the subspecies labeled "E. c. caballus" (domesticated horse), "E. c. ferus" Boddaert, 1785 (tarpan) and "E. c. przewalskii" Poliakov, 1881 (Przewalski's horse). However, in 2003, the International Commission on Zoological Nomenclature decided that the scientific names of the wild species have priority over the scientific names of domesticated species, therefore mandating the use of "Equus ferus" for the horse, independent of the position of the domesticated horse. Przewalski's horse occupied the eastern Eurasian Steppes, perhaps from the Urals