Equidae is the taxonomic family of horses and related animals, including the extant horses, asses, and zebras, and many other species known only from fossils. The family evolved around 50 million years ago from a small, multi-toed ungulate into larger, single-toed animals. All extant species are in the genus Equus, which originated in North America. Equidae belongs to the order Perissodactyla, which includes the extant tapirs and rhinoceros, and several extinct families. It is more specifically grouped within the superfamily Equoidea, the only other family being the extinct Palaeotheriidae.
The onager (Equus hemionus), also known as hemione or Asiatic wild ass, is a species of the family Equidae native to Asia. A member of the subgenus Asinus, the onager was described and given its binomial name by German zoologist Peter Simon Pallas in 1775. Six subspecies have been recognized, two of which are extinct.
Equus is a genus of mammals in the family Equidae, which includes horses, asses, and zebras. Within the Equidae, Equus is the only recognized extant genus, comprising seven living species. Like Equidae more broadly, Equus has numerous extinct species known only from fossils. The genus originated in North America and dispersed into the Old World and South America during the Early and Middle Pleistocene. Equines are odd-toed ungulates with slender legs, long heads, relatively long necks, manes, and long tails. All species are herbivorous, and mostly grazers, with simpler digestive systems than ruminants but able to subsist on lower-quality vegetation.
Equus scotti is an extinct species of horse native to Pleistocene North America.
Equus lambei, commonly known as the Yukon horse or 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.
Equus sivalensis is an extinct species of large equid native to the northern Indian subcontinent. Remains date from the beginning of the Pleistocene, c. 2.58 million years ago until around 600,000 years ago, during the Middle Pleistocene. It is considered a "stenonine horse", meaning that it is more closely related to zebras and asses than true horses. Based on isotopes and teeth morphology, it is thought to have been a grazer. The later species Equus namadicus from the same region has sometimes been suggested to be a synonym due to their similar teeth morphology.
Equus namadicus is a prehistoric equid, known from remains dating to the Middle and Late Pleistocene from across the Indian subcontinent, with its last dated records being approximately 29-14,000 years ago. It is considered a "stenonine horse", related to species like the European Equus stenonis, meaning that it is probably more closely related to zebras and asses than true horses. It is relatively large in size. It is very similar to the earlier Equus sivalensis, also from the Indian subcontinent, from which it only differs in size and in subtle aspects of dental anatomy, and it has sometimes been suggested to be a synonym of it.
The evolution of the horse, a mammal of the family Equidae, occurred over a geologic time scale of 50 million years, transforming the small, dog-sized, forest-dwelling Eohippus into the modern horse. Paleozoologists have been able to piece together a more complete outline of the evolutionary lineage of the modern horse than of any other animal. Much of this evolution took place in North America, where horses originated but became extinct about 10,000 years ago, before being reintroduced in the 15th century.
Plesippus is a genus of extinct horse from the Pleistocene of North America. Although commonly seen as a subgenus of Equus recent cladistic analysis considers it a distinct genus.
The Hagerman Horse Quarry is a paleontological site containing the largest concentration of Hagerman horse fossils yet found. The quarry is within Hagerman Fossil Beds National Monument, located west of Hagerman, Idaho, USA, at the geographic division of the Snake River Plain. The Hagerman Horse Quarry is an integral part of the monument and is located on the northern flank of Fossil Gulch in the northern portion of the monument.
Megahippus is an extinct genus of large Anchitheriine horses found throughout the southern portion of the United States during the middle Miocene. The animal represents one of the latest low-crowned horses, overlapping in time with more derived high-crowned horses.
Equus neogeus is an extinct species of equine native to South America during the Pleistocene. It was formerly thought to be several distinct species within the subgenus Amerhippus, but was later shown to be a single morphologically variable species. It is thought to be closely related to true horses.
Hipparionini is a tribe of three-toed horses in the subfamily Equinae. They had body forms similar to modern equines, with high-crowned teeth. They first appeared in North America during the Early Miocene around 17 million years ago, before migrating into the Old World around 11.4-11.0 million years ago. The youngest species date to the Early Pleistocene, becoming extinct following the arrives of modern equines of the genus Equus to the Old World.
Eurygnathohippus is an extinct genus of hipparionine horse. The majority of known fossils of members of this genus were discovered in Africa, where members of this genus lived during the late Miocene to Pleistocene interval. Fossils of Eurygnathohippus were also reported from the late Pliocene sediments of the Potwar Plateau in Pakistan and the Siwalik Hills in northwest India.
Paleontology in Idaho refers to paleontological research occurring within or conducted by people from the U.S. state of Idaho. The fossil record of Idaho spans much of the geologic column from the Precambrian onward. During the Precambrian, bacteria formed stromatolites while worms left behind trace fossils. The state was mostly covered by a shallow sea during the majority of the Paleozoic era. This sea became home to creatures like brachiopods, corals and trilobites. Idaho continued to be a largely marine environment through the Triassic and Jurassic periods of the Mesozoic era, when brachiopods, bryozoans, corals, ichthyosaurs and sharks inhabited the local waters. The eastern part of the state was dry land during the ensuing Cretaceous period when dinosaurs roamed the area and trees grew which would later form petrified wood.
Equus stenonis is an extinct species of equine that lived in Western Eurasia including Europe during the Early Pleistocene.
The giant horse is an extinct species of horse which lived in North America.
Equus altidens is an extinct species of equine native to western Eurasia including Europe during the Early Pleistocene to early Middle Pleistocene.
Equus major is an extinct species of large equine native to Europe during the Early Pleistocene epoch.
Equus suessenbornensis is an extinct species of large equine native to Western Eurasia, including Europe, during the Early Pleistocene to early Middle Pleistocene.
