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Related to Equidae: Equids


(vertebrate zoology)
A family of perissodactyl mammals in the superfamily Equoidea, including the horses, zebras, and donkeys.



a family of the order Perissodactyla. It comprises three subfamilies with approximately 20 genera, including extinct genera (such as Hyracotherium, Anchitherium, Mesohippus, Miohippus, Merychippus, Hipparion, and Pliohippus) and the only surviving genus, Equus.

The family comprises animals varying greatly in appearance and structure. With the exception of the most ancient (Eocene) representatives, equids are well-proportioned animals, with long legs and a very developed large third toe encased in a hoof; the second and fourth toes are greatly reduced (they are absent in modern equids). The facial part of the skull is greatly elongated. The cheek teeth are hypsodont and grow as they wear down. The equids evolved so as to adapt to fast running in open spaces and eating coarse vegetation. During the evolutionary process, the legs lengthened, the joints straightened, the middle toe enlarged, and the side toes gradually reduced. The face lengthened as the molars grew larger, and the premolars acquired a molar-like appearance and a complex folded chewing surface.

The history of the family Equidae has been well studied in North America, where they lived from the early Eocene epoch to the late Pliocene epoch. In the eastern hemisphere, in different geological periods there existed representatives of the family that were not linked to one another evolutionarily. The ancestors of the modern equids came to the eastern hemisphere from North America in the late Pliocene epoch, and in different parts of their vast area of distribution gave rise to different groups of modern equids. The history of the family’s development studied in detail by V. O. Kovalevskii is a classic example of research into the specific evolutionary paths of a large group of animals.


Kovalevskii, V. O. Sobranie nauchnykh trudov, vol. 2. Moscow, 1956.
Osnovy paleontologii: Mlekopitaiushchie. Moscow, 1962.
Simpson, G. G. Horses. New York, 1951.


References in periodicals archive ?
But, as we have seen, the horses restrict their phylogenetic philosophizing to the evolution/ degeneration of the subjected Yahoo species, showing absolutely no interest in the origins and development of their own genus, the Equidae.
Kardela (1992), Kleparski (1996, 1997), Krzeszowski (1997), Lakoff and Johnson (1980), Lakoff (1987), Lakoff and Turner (1989), Langacker (1987), Martsa (2001), we will analyse those lexemes linked to the categories EQUIDAE, CANIDAE and FELIDAE which in their semantic history have undergone zoosemic development, targeted at the conceptual category FEMALE HUMAN BEING.
The evolutionary strategy of the equidae and the origins of rumen cecal digestion.
Dentro de un area de 1 m2 de excavacion, se registraron diversos restos del esqueleto apendicular y axial de especies extintas pertenecientes a las familias Camelidae, Cervidae, Cricetidae, Artiodactyla, Equidae, Mylodontidae, Canidae y restos del Orden Xenarthra, que fueron recuperados en concentraciones discretas dispuestas sobre una unidad estratigrafica caracterizada por una grava arcillosa en una matriz de arena fina a limo y arcillas con presencia de lentes de carbon.
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Washington, Dec 11 (ANI): Scientists studying ancient DNA from extinct horse species have discovered new evidence on the evolution of Equidae over the past 55 million years.
All equidae will now have to acquire their individual passports within six months after their birth and these animals will be tagged with an electronic chip corresponding to their passport.
The Horse Passports (England) Regulations 2003 which came into effect on November 30 will eventually change the whole Equestrian Industry face as it gathers momentum towards the deadline of June 30, 2004, when all equines and equidae will require a passport or a revised updated version.
Tenders are invited for AGREEMENT - FRAMEWORK FOR SERVICES surveillance, prevention, control and eradication of animal diseases, THOSE transmissible from animals to humans, animal protection and environmental protection, identification and registration of cattle, swine, sheep, goats and EQUIDAE 2016-2020