Wild Yak | abioticfactor

Wild Yak - Bos mutus

A wild yak lives between 3000 and 5500m above sea level.

According to altitude.org, at 5500m, the standard barometric pressure is 53 kPa. Only 52% of the oxygen is available than at sea level.

Cattle have 13 thoracic vertebrae and rib pair. However, the Yak has 14-15 pairs of ribs. Cattle also have 6 lumbar vertebrae and the Yak only 5. They therefore have a larger chest capacity giving room to their larger than average size heart and lungs.

Cattle Yak

Wang Yuchang (1995) suggested that Yaks are able to consume more air due to having a wider nose and trachea than other cattle.

Research conducted in 1958 by Denisov discovered that the transection of a yak’s lung has 19% more alveolar than other cattle. Thus resulting in a larger surface area and more oxygen absorption.

A study by Belkin et al (1985) suggested that there is more capillarisation in the right ventricle than the left ventricle of yak hearts. The purpose of the right ventricle of the heart is to pump oxygen deficient blood to the lungs, thus being an highly important role for oxygen intake.

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Wild Yak - Bos mutus

Cattle Yak

The yak genome and adaptation to life at high altitude