Adapting to -70 degrees in Siberia: A tale of Yakutian horses

http://www.eurekalert.org/pub_releases/2015-11/fos--at-112015.php

Public Release: 23-Nov-2015
Adapting to -70 degrees in Siberia: A tale of Yakutian horses
Faculty of Science - University of Copenhagen

From an evolutionary perspective it happened almost overnight. In less than 800 years Yakutian horses adapted to the extremely cold temperatures found in the environments of eastern Siberia. The adaptive process involved changes in the expression of a plethora of genes, including some also selected in human Siberian groups and the extinct wooly mammoth.

In a new scientific study, the comparison of the complete genomes of nine living and two ancient Yakutian horses from Far-East Siberia with a large genome panel of 27 domesticated horses reveals that the current population of Yakutian horses was founded following the migration of the Yakut people into the region in the 13-15th century AD. Yakutian horses, thus, developed their striking adaptations to the extreme cold climate present in the region in less than 800 years. This is one of the fastest examples of adaptation within mammals.

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Horses have been essential to the survival and development of the Yakut people, who migrated into the Far-East Siberia in the 13-15th century AD, probably from Mongolia. There, Yakut people developed an economy almost entirely based on horses. Horses were indeed key for communication and keeping population contact within a territory slightly larger than Argentina, and with 40 % of its surface area situated north of the Arctic Circle. Horse meat and hide have also revealed crucial for surviving extremely cold winters, with temperatures occasionally dropping below -70C.

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It provides a compelling example of evolutionary convergence, where unrelated groups exposed to similar environments end up independently developing similar adaptations.

Such genes showing convergent signals of adaptation include in humans PRKG1, which is involved in the shivering response to cold, and BARX2 in the woolly mammoth which is involved in hair development.

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