Yak Domestication: A Review of Linguistic, Archaeological, and Genetic Evidence

Abstract

Yak, a species of bovid uniquely adapted to high-altitude environments, plays a critical role in the life of the inhabitants of the Tibetan Plateau and neighboring areas. There is currently no consensus on when these animals may have been domesticated. In this paper, we review the archaeological, genetic, and linguistic evidence relevant to this question, and suggest that the domestication took place following hybridization with taurine cattle from the end of the fourth millennium BCE. This study also shows that the original domesticators of yaks included not only the ancestors of the Tibetans, but also Rgyalrongic speaking people from Eastern Tibet.

Evidence for early domestic yak, taurine cattle, and their hybrids on the Tibetan Plateau

“…Genomic evidence for hybridization between yak and cattle indicated adaptive introgression, likely associated with intentional selection (e.g., culling, castration, or breeding of individual yak or cattle) to reduce environmentally related mortality and to increase productivity (e.g., milk, meat, and traction). Large-scale aDNA sampling at earlier sites is needed to address the question of whether hunter-gatherers or earlier herders influenced initial domestication processes ( 9 ).…”

“…These include early selection on wild yak by mid-Holocene hunter-gatherers and/or late yak domestication at approximately 4000 to 3000 calibrated radiocarbon years before the present (cal B.P. ), somewhat after the introduction of domestic sheep, goat, wheat, and barley to the region and cattle first appearing on the northeastern margins of the plateau (7,9,14,(18)(19)(20)(21).…”

“…1 ). Contemporary highland pastoralists rely on the strength and hardiness of domestic yak for transportation across vast mountainous terrain and for supplies of milk, meat, fiber, and dung for fuel ( 9 ). Cattle and yak-cattle hybrids complement yak, supporting herders under different conditions.…”

“…Exploration of the early history of bovine (cattle, yak, and hybrids) husbandry on the high Tibetan Plateau has been hindered by a lack of archaeological data because yak remains are rare, osteological discrimination between wild and domestic yak has not been fully investigated, and early cattle bones have seldom been found outside the northern fringes of the Tibetan Plateau. Arguments based on modern genetic data on yak population expansion and information on pollen and linguistic shifts suggest two possible scenarios for yak domestication ( 9 ). These include early selection on wild yak by mid-Holocene hunter-gatherers and/or late yak domestication at approximately 4000 to 3000 calibrated radiocarbon years before the present (cal B.P.…”

Dairying and the evolution and consequences of lactase persistence in humans

“…There appears to be active management of taurine cattle in the early Holocene before the introduction of domestic cattle in the later Holocene ( Zhang et al, 2013 ). Yak were domesticated in the mid-Holocene on the Tibetan Plateau, perhaps as result of hybridization with domestic Taurine cattle ( Jacques et al, 2021 ). Further domestication of plant and animal species occurred in the early and mid-Holocene of the equatorial Africa, the Americas, and Papua New Guinea, but these domestication events are not thought to generally relate to the origins of dairying.…”