Domestic Bactrians did not descend from today's wild camels
The two-humped Bactrian camel carried Inner Asian trade through cold, drought, and thin air. It shares genus Camelus with the dromedary and the wild Bactrian, yet genetics say the domestic line is not simply tamed from surviving wild herds.
About 2 million Bactrian camels exist, almost all domesticated, named after the ancient region of Bactria. Aristotle, in the 4th century BCE, was the first European to distinguish them from the one-humped Arabian camel. Although closer kin to the wild Bactrian than to the dromedary, the domestic animal split from its wild cousin long ago; their mitochondrial lineages diverged roughly a million years back. Both are related to an extinct giant, Camelus knoblochi, which died out around 20,000 years ago, and camelids themselves arose in North America some 30 million years ago before crossing the Bering land bridge.
It is the largest living camel, though shorter at the shoulder than a dromedary: 160 to 180 centimetres at the shoulder, around 213 at the hump tops, and 300 to 1,000 kilograms, with males averaging near 600. The humps store fat, not water, and slump sideways when food runs short. Long lashes and closable nostrils keep out sand, and the shaggy winter coat, rated from minus 30 to 50 degrees Celsius, peels off in great sheets in spring as though badly shorn.
Water economy is its superpower. A Bactrian can go months without drinking, yet a thirsty animal in the hot season may take in 200 litres in a day. It is one of the few animals that routinely eats snow for water, taking small mouthfuls because melting ice costs so much body heat. Tough mouths let it chew thorny, salty or bitter plants, and in hard times it will gnaw bones and carcasses.
Females ovulate only after mating, triggered by seminal fluid rather than sperm. Gestation lasts about 13 months, and the calf, averaging 36 kilograms, can stand and run soon after birth; mothers usually breed every other year. Herders from Mongolia to Iran value hardiness, milk and load-carrying, and in Kazakhstan and Uzbekistan artificial insemination is increasingly used. Hybrids with dromedaries are fertile, and where the two overlap in Iran and Afghanistan their differences blur.
Source: Bactrian camel
