The Horse (Equus caballus) is a sizeable ungulate mammal, one of the ten modern species of the genus Equus. It has long played an important role in transport, whether ridden or used for pulling vehicles. They are also used for food. more...
Though horses may have been domesticated in one isolated locale in 4500 BC, the unequivocal date of (1) domestication and (2) use as a means of transport dates to no earlier than circa 2000 BC, evidenced by the Sintashta chariot burials (see Domestication of the horse).
Nevertheless, a close cousin of the horse, the donkey, was likely domesticated and used for transport circa 3000 BC (see discussions at Donkey and ).
Until the mid 20th century, armies used horses extensively in warfare: soldiers still call the groups of machines that now take the place of the horse on the battlefield "cavalry" units, sometimes keeping traditional names (Lord Strathcona's Horse, et cetera).
Domestication of the horse and surviving wild species
The earliest evidence for the domestication of the horse comes from Central Asia and dates to about 4,000 BCE. Competing theories exist about the time and place of domestication. However, wild species continued into historic times, including the Forest Horse, Equus ferus silvaticus (also called the Diluvial Horse); it is thought to have evolved into Equus ferus germanicus, and may have contributed to the development of the heavy horses of northern Europe, such as the Ardennais.
The Tarpan, Equus ferus ferus, became extinct in 1880. Its genetic line is lost, but a substitute has been recreated by "breeding back", crossing living domesticated horses that had features selected as primitive, thanks to the efforts of the brothers Lutz Heck (director of the Berlin zoo) and Heinz Heck (director of Tierpark Munich Hellabrunn). The resulting animal is more properly called the Wild Polish Horse or Konik.
Only one true wild-horse species survives: Przewalski's Horse, Equus ferus przewalskii, a rare Asian species. Mongolians know it as the taki, while the Kirghiz people call it a kirtag. Wild populations exist in Mongolia; see:
Wild vs. feral horses
One can distinguish between wild animals, whose ancestors have never undergone domestication, and feral animals, who had domesticated ancestors but who now live in the wild. Several populations of feral horses exist, including those in the West of the United States and Canada (often called "mustangs") and in parts of Australia (called brumbies) and in New Zealand (called "Kaimanawa horses"). These feral horses may provide useful insights into the behavior of their ancestral wild horses.
The Icelandic horse (pony-sized but called a horse) provides an opportunity to compare contemporary and historical breed appearances and behaviour. Introduced by the Vikings into Iceland, Icelandic horses did not subsequently undergo the intensive selective breeding that took place in the rest of Europe from the middle ages onwards, and so they consequently bear a closer resemblance to pre-medieval breeds. The Icelandic horse has a four-beat gait called the "tölt", which equates to the rack exhibited by several American gaited breeds.
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