Equus (genus) and pioneer spirit of the West" under the Wild and Free-Roaming Horses and Burros Act of 1971, and in "Kleppe v. New Mexico", the United States Supreme Court ruled that the animals so designated were, as a matter of law, wildlife. Equus (genus) Equus is a genus of mammals in the family Equidae, which includes horses, donkeys, and zebras. Within Equidae, "Equus" is the only recognized extant genus, comprising seven living species. The term equine refers to any member of this genus, including horses. Like Equidae more broadly, "Equus" has numerous extinct species known only from fossils. The genus most
Equus lambei Equus lambei Equus lambei (common names include Yukon horse, and Yukon wild horse) is an extinct species of the genus "Equus". "Equus lambei" ranged across North America until approximately 10,000 years ago. Based on recent examinations of the mtDNA of "Equus lambei" remains, scientists have concluded that "E. lambei" was probably much like the extinct Tarpan, also known as the Eurasian wild horse, and the living Przewalski's Horse. A partial carcass of "Equus lambei" is on display at the Yukon Beringia Interpretive Centre in Whitehorse, Yukon. Evidence from "E. lambei" mtDNA has shown that "Equus lambei" is a close relative