Equus scotti
Equus scotti is an extinct species of horse native to Pleistocene North America.
Evolution
Equus scotti is a true caballine horse that is more closely related to modern horses than to zebras and asses. The taxonomy of North American Pleistocene caballine "stout legged" horses is highly convoluted and controversial, with numerous named species including Equus lambei, Equus niobarensis, Equus occidentalis and Equus conversidens, that may in reality represent a few or only one true species. Although it has been suggested that Equus scotti and other North American caballine horses may be synonymous with living Eurasian Equus ferus, ancient DNA indicates that North American horses are genetically distinct from their Eurasian counterparts, having diverged from them around 800,000 years ago, following the first dispersal of horses out of North America, with some interbreeding after the initial split.The earliest remains of the species are known from the late Blancan during the Early Pleistocene. The youngest remains of the species date to the Late Pleistocene around 12,000 years ago.
Distribution
Paleontological excavations have identified the locations of numerous places where E. scotti occurred. The species was named from Rock Creek, Texas, United States, where multiple skeletons were recovered. A closely related fossil find was made of Equus bautistensis in California; this species appeared closely related, but of a slightly more primitive form than E. scotti. However, E. bautistensis was redefined as a junior synonym of E. scotti in 1998 by paleontologist E. Scott, who also assigned fossils from the Anza-Borrego Desert in California, tentatively interpreted to represent E. bautistensis, to E. scotti.The distribution of the species includes: "Alberta, Ontario, Saskatchewan and Yukon and in California, Florida, Idaho, Kansas, Nebraska, New Mexico, Oklahoma and Texas ".