Mouflon vignei" (or "orientalis") "arkal" and "O. v./o. bochariensis", grouped with two different clades of argali ("Ovis ammon"). The ancestral sheep is presumed to have had 60 chromosomes, as in goats ("Capra"). Mouflon and domestic sheep have 54 chromosomes, with three pairs (1+3, 2+8, 5+11) of ancestral acrocentric chromosomes joined to form bi-armed chromosomes. This is in contrast to the argali and urial, which have 56 and 58 chromosomes respectively. If the urial is as closely related to the mouflons as mitochondrial DNA indicates, then two chromosomes would need to have split during its evolution away from the mouflon (sub)species. In
Wild horse stock from which domesticated horses are descended. The horse family Equidae and the genus "Equus" evolved in North America, before the species moved into the Eastern Hemisphere. Studies using ancient DNA, as well as DNA of recent individuals, show the presence of two closely related horse species in North America, the wild horse and "Haringtonhippus francisci", the "New World stilt-legged horse"; the latter has been taxonomically assigned to various names. Currently, three subspecies that lived during recorded human history are recognized. One subspecies is the widespread domestic horse ("Equus ferus caballus"), as well as two wild subspecies: the recently extinct