The modern domesticated horse (Equus caballus) is found throughout the world and is counted as one of the most diversified creatures in existence. In North America, the horse was endangered in the late Pleistocene, but 2 wild subspecies survived until years ago, the Tarpan (Equus ferus ferus), which became extinct in 1919) and the Przewalski horse (Equus ferus przewalskii) , of which there are currently a small number).
The history of the horse, especially the part that talks about domestication, continues to be debated, because the evidence itself is debatable. Unlike other animals, criteria such as the change in body morphology (horses are very diverse) or the location of a particular horse outside its normal distribution (horses are highly distributed animals) are not helpful in helping to solve the problem.
The first indications of domestication are related to the presence of what appeared to be a pile of animal excrement in an area delimited by posts, which experts interpret as representing a horse corral. These evidence were found in Krasny Yar, Kazakhstan, in areas dating back to 5000 BC and it is believed that the horses may have been kept as a source of food and milk, rather than used for riding or carrying.
Accepted archaeological evidence for horsemanship includes little wear on horse teeth, which has been found in the steppe east of the Ural Mountains at Botai and Kozhai in present-day Kazakhstan, around 3500-3000 BC. The little wear on the teeth of some of the archaeological remains found suggests that several of them were mounted for hunting and others were used for food and milk consumption. Finally, the earliest evidence for the direct use of horses as pack animals, in the form of drawings of horse-drawn carriages, was found in Mesopotamia, around 2000 BC.
Three lines of evidence for the domestication of the horse
In a 2009 Science paper, Alan K. Outram and his colleagues examined three lines of evidence for the domestication of horses in areas of Botai culture. The data that were found support the theory of the domestication of the horse between approximately 3500 and 3000 BC in what is now Kazakhstan.
The skeletons found had graceful metacarpals, this area and some bones such as the tibia, are parts of the body that are analyzed as key indicators of domesticity, since for example, the tibia in domestic horses is thinner than in wild horses.
Other elements found in this area were the remains of fatty lipids from horse milk in the vessels, evidence of the consumption of their meat, wear on the teeth and graves that buried the bodies of riders.
Other studies examined the DNA of thoroughbred racehorses and identified the specific allele that genetically controls speed and earliness. Thoroughbreds are a specific breed of horse, descended from the sons of one of three stallions known as the Byerley Turk, imported to England in the 1680s, the Arabian Darley (1704) and Godolphin Arabian (1729). The history of thoroughbred horse breeding has been recorded in the General Herd Book since 1791, and genetic data supports this history.
Horse races in the 17th and 18th centuries ranged from 3,200 to 6400 meters, and the horses were between 5 and 6 years old. In the early 1800s, the Thoroughbred horse was bred for its speed and endurance, characteristics that allowed it to run great distances at just 3 years of age.
Genetic studies looked at the DNA of hundreds of horses and approved the C-type myostatin variant gene, concluding that it had its origin from a single mare, descended from one of the three stallions 300 years ago.