Scientists have found the genetic basis of domestication of the horse
Scientists have decoded the genome of ancient horses, whose bones have been observed in Northern Siberia, and found the genetic results of domestication of these animals. The results of research biologists presented in the journal Proceedings of the National Academy of Sciences.
Louis Orlando (Ludovic Orlando) from the Copenhagen Institute and his colleagues sequenced the genomes of old horses from Taimyr (their remains are dated to the 14th and 41st millennia before our era) and compared them with the genomes of 5 progressive rock and Przewalski's horse (the only living descendant of the extinct unbridled horses of Eurasia).
Scientists have identified at least 125 sites that have changed under the influence of domestication. the 1st group of genes associated with the development of muscles, joints, limbs, and even cardiovascular system. These genes are changed under the action of the latest physical activity, formed in consequence of the use of horses in home activities. the 2nd group of genes affects social behavior, learning, reaction of fear, aggression levels - specifically they will likely have provided the reincarnation of wild horses in a tame animal, understanding commands on this planet.
In the end, in the genomes of advanced horses found a large number of harmful mutations. Presumably, the cost of inbreeding (closely related crosses that are inevitable when synthetic selection. This fact is again confirmed the guess about the price of domestication, proven during the study of the genomes of rice, tomatoes and dogs: the demographic limitations of population is inevitable when selecting animals for domestication, lead to the weakening of the "cleansing" of natural selection.
In 2001 the Swedish biologists presented the results of a comparative study of the mitochondrial DNA of living and fossil horses. Genetic diversity of this species was greater than that of the other animals. The authors hope that domestication occurred independently in different places, or to genotype often added genes mares, captured in the wild.
The domestication of horses in Eurasia happened, according to various estimates, in the IV-III Millennium before our era. Over time people have learned to ride, have invented a saddle and stirrups (in the IV century ad).
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