Domestication of the horse
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There are a number of theories regarding the domestication of the horse. Although horses appeared in Paleolithic cave art as early as ca 30,000 BC, these were truly wild horses and were probably hunted for meat; how and when horses became domesticated is less clear. The most common date of domestication and use as a means of transport is c. 2000 BC, although in the Kurgan hypothesis the domestication of horses is dated as early as 4500 BC.
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Older theories (pre-1999)
Before the common use of DNA in such research, anthropologists and evolutionary biologists had to content themselves with studying features of existing animals and comparing them to preserved specimens from the past—frozen remains, other preserved remains, and sub-fossils. For horses, the data led to the hypothesis that horses were domesticated in one small area on the grassland steppes of Eurasia, perhaps around 4600 BC.
Theories from DNA evidence
More recently, a comparative study of mitochondrial DNA (mtDNA) from living and fossil horses suggests that horses were domesticated in many places, at many times.
Evolutionary biologists at Uppsala University in Sweden studied mitochondrial DNA from 191 pedigree horses (Vilà et al., 2001), including examples of historical English and Swedish breeds considered primitive and one breed derived from animals imported to Iceland by the Vikings. They also obtained DNA samples from Przewalski's horse, a small Mongolian equine thought by some to be a sister species to the original wild horses. They compared these samples with fossil DNA from leg bones of horses that have been preserved in the Alaskan permafrost for more than 12,000 years and with other samples from 1000- to 2000-year-old archaeological sites in southern Sweden and Estonia.
The analysis of mitochondrial DNA showed that the modern horses had almost as much genetic variation as samples of fossil horses. By contrast, similar analyses of mitochondrial DNA had shown that modern individuals from cattle, sheep, water buffalo, and pig breeds are much less genetically diverse than their ancient forbears. That a large number of wild lineages have been involved in the domestication, many more than in any other domestic mammal, would suggest that the domesticated horse had ancestors in many places, implying that domestication occurred in many areas.
Investigations by professor G. Lindgren et al., Uppsala, published in Nature Genetics 2004 has revealed that all horses, big and small, probably descend from one single stallion. These investigations were performed on chromosome Y. On the other hand, similar investigations showed that there are at least a hundred different maternal ancestors but if we go deeper in time then fewer.
Location and time of domestication
The time of domestication is also difficult to establish, and here again there seem to be several camps. One claim is that evidence at several sites shows equine tooth wear that only could result from the friction of a bit against the molars, indicating captive animals (but not necessarily domesticated). Sites include Dereivka, a Ukrainian settlement site (circa 4500–3500 BC), and sites identified as the Botai culture, dated 3500–3000 BC in the northern steppes of Kazakhstan, east of the Ishim river. Not all molars at the sites showed bit wear: one idea is that the horses with bit wear were cult animals and were kept as objects of veneration. Another idea is that there would be a large population of equines in the area; some would be captive and others would remain wild. The captive animals would be used to hunt the wild individuals; only the captive animals would show bit wear.
Another camp resists this evidence because there are no skeletal changes that would provide secure proof that the horses were actually domesticated -- that is, bred in captivity -- and not merely tamed. Marsha A. Levine, one of the foremost researchers in this field, points out that traditional peoples world wide (both aboriginal hunter-gatherers and horticulturists) tame individuals from wild species, typically by hand-rearing infants whose parents have been killed. A species cannot be said to be truly domesticated until it will reliably breed in captivity.
Levine's model of horse domestication starts with individual foals being kept as pets while the adult horses were slaughtered for meat. Foals are relatively small and easy to handle. Horses, being herd animals, need companionship to thrive, and the modern data show that foals can and will bond to other domestic animals to meet their intimacy needs. Levine envisions horses being repeatedly made into pets over time, preceding the great discovery that these pets could be put to work.
The traditional scenario, in which the horse would have been domesticated in one isolated locale in the 5th millennium BC, is not without some serious anthropological puzzles. For instance, how could the Ukraine's indigenous nomadic hunter-gatherers proceed to the sophistication of proto-Tocharian disk-wheeled ox-drawn wagons in such a short time span? Template:Ref Use of the wheel in this fashion commonly appears much later in the historical record (see Wheel), and wagon construction techniques require advances in carpentry that might seem beyond the reach of Neolithic peoples (see History of Ukraine). Also questioned is why these advanced peoples suddenly appear and then disappear from the local archaeological record. External influences are suggested but unknown; others may suggest transported evidence Template:Fact.
As Levine points out, the unequivocal date of domestication and use as a means of transport is circa 2000 BC, the date of the Sintashta chariot burials in the southern Urals. However, shortly thereafter the expansion of the domestic horse throughout Europe was little short of explosive. In the space of possibly 500 years, there is evidence of horse-drawn chariots in Greece, Egypt, and Mesopotamia. By another 500 years, the horse-drawn chariot had spread to China.
Chariot driving versus riding
Another more difficult question posed for time and locale is whether the domestication of the horse or the invention of the wheel occurred first. This would have dictated whether technology or technique of equestrianism or chariot driving would have affected ancient warfare first.
David W. Anthony, one of the co-founders of the Institute for Ancient Equestrian Studies, wrote (Anthony, 1998):
- "The Dereivka stallion exhibits bit wear made by a hard bit - perhaps bone. The amount of wear would have required at least 300 hours of riding with a hard bit, according to our experiments. If the deposit containing the stallion skull and mandible dates to about 4000 BC, as Brown, Telegin and I would argue, it pre-dates the invention of the wheel. If the bit wear at Dereivka precedes the introduction of wheeled vehicles, it probably resulted from riding. The bit wear at Dereivka is the earliest evidence for the use of horses as transport animals anywhere in the world. "
However, there is dissent in regard to this answer, as a bit could be used to lead a horse, being seen as far less stressful than leading it by binding its neck. A horse could easily have been led by fastening a bit between its teeth that was connected to a leash, and conveying it to pull a primitive plow. Since oxen were usually relegated to this duty in Mesopotamia, two-thousand years before the generalised date of horse use in more northern climes, it could be guessed that elsewhere early plows might have been attempted with the horse, and a bit may indeed have been significant as part of agarian development rather than equestrian technology. Analysis on equine remains should also focus on shoulder and spine stress, to determine if heavy pressure such as a plow can be discerned.
Ancient or early-domesticated horses were relatively small by modern standards, perhaps Horse#Specialized vocabulary 12.2 to 14.2 hands high or 1.27 to 1.47 meters, measured at the shoulder. The small stature of these horses, compared to modern riding horses of 15.2 to 17.2 hh (1.6 to 1.8 meters), led theorists to believe the ancient horses were too small to be ridden and so must have been driven.
However, this does not necessarily tally with the strength of equivalent modern breeds; for example Fell ponies, believed to be descended from Roman cavalry horses, are comfortably able to carry fully grown adults (although with rather limited ground clearance) at an average height of 13.2 hands (1.37 m).
As such, the understanding of early horse domestication will continue to evolve and continue to be hotly debated.
Notes
- Template:Note Read 5000 bc. to 4000 bc., [1] Shippensburg University)
See also
- horse
- Equestrian nomad
- Evolution of the Horse
- list of horse breeds
- horse breaking
- horse breeding
- horse tack
- horse teeth
- Trojan Horse
References
- Anthony, David W. (1998). The opening of the Eurasian steppe at 2000 BC. In The Bronze Age and Early Iron Age Peoples of Eastern Central Asia, ed. Victor H. Mair, vol. 1. (Journal of Indo-European Studies Monograph 26). Washington, D.C.: The Institute for the Study of Man.
Lindgren, G., Backström, N., Swinburne, J., Hellborg, L., Einarsson, A., Sandberg, K., Vilà, C., Binns, M. & Ellegren, H. (2004) Limited number of patrilines in horse domestication. Nature Genetics 36: 335-336.
- Vilà, C, Leonard, JA, Götherström, A, Marklund, S, Sandberg, K, Lidén, K, Wayne, RK, and Ellegren, H. (2001). Widespread origins of domestic horse lineages. Science 291: 474-477.