Bos grunniens

• During the mating season, a yak produces a loud bellow, while in other periods it almost does not make sounds.
• The yak's dense, matted undercoat protects it from winter cold and sheds in large clumps in spring and summer.
• The yak reaches a withers height of up to 2 m, and the mass of old bulls can reach up to 1000 kg. The body length of an old male can reach 4.25 m, of which 0.75 m is the tail.
• Wild yaks avoid areas inhabited by humans and are therefore rapidly disappearing — they now live only in high-altitude regions of Tibet at elevations of 4300–4600 m above sea level in winter and up to 6100 m in summer.
• The cattle family includes wild (mutus — "silent") and domestic (grunniens — "grunting") yaks. This difference is related to their origin and behavior.
• The yak's tail is covered with long, stiff hair and resembles a horse's. Long, shaggy fur on its legs, sides, and belly forms a dense "skirt.