Wild Bactrian camels have a long and fascinating history. They have roamed the barren and rocky deserts of China and Mongolia for thousands of years. However, both Bactrians and their one-humped cousins, the dromedaries (or Arabian camels; now extinct in the wild), originated in North America between 40 million and 45 million years ago. Their divergence from their lamoid relatives—the domestic alpacas and llamas and the wild guanacos and vicuñas—took place about 11 million years ago and was followed by a long migration to southwest Asia, northern Africa, and the Gobi desert.
Two lineages
Recent investigations have indicated that following the migration of Bactrian camels across the Bering Strait and into Asia, the population diverged into two lineages. This split is believed to have occurred about 700,000 years ago, with one lineage eventually being domesticated. The taming of wild Bactrians to suit human needs is believed to have occurred initially in the Gobi desert, with the process complete possibly by as early as 4000 BCE in China. About 1,500 years later, the domestic camels appeared in the ancient Greek kingdom of Bactria, for which the camel is named. Bactria occupied a large region, which now forms part of modern-day Afghanistan, Uzbekistan, Tajikistan, and Turkmenistan.
Two young Bactrian camels in winter steppe, Kyrgyzstan. The geographic range of domestic Bactrians was tied to the animals’ use in trade and travel, which significantly influenced the growth of human civilizations across Asia. The geographic locations where Bactrians were first domesticated is known from evidence of human use; domestic camels appear to have originally occupied a habitat extending from Bactria, to the western edge of modern-day Gansu province in northwestern China and to the Gobi in north-central China. This range overlaps with many of the same areas that were once occupied by their wild counterparts. In addition, the geographic isolation of certain domestic Bactrian populations has led to the rise of subspecies of domestic camel.
The few wild Bactrians remaining today can be divided into subpopulations that exist within just four distinct regions: the Altun mountains in the Uygur Autonomous Region of Xinjiang, in northwestern China; the Great Gobi Strictly Protected Area in Mongolia; the Gaxun Gobi, a region encompassing the western portion of the Gobi desert within China; and the Takla Makan Desert, in west-central China. Unfortunately, the subpopulation previously reported in the Takla Makan is now suspected to be extinct, since wild Bactrians have not been sighted there for some time.
Today, despite the listing of wild Bactrians as critically endangered by the International Union for Conservation of Nature (IUCN), they are disappearing at an alarming rate. About 20 are killed each year in China for human subsistence, and in Mongolia, another 25 to 30 are killed annually by humans and natural predators. At this pace, wild Bactrians, which have a life span of 40 to 50 years, will go extinct within two or three generations.
The human-induced decline of wild Bactrians has increased their susceptibility to nature. Even though wild Bactrians, with their fat-storing humps and dehydration-preventing kidneys, are magnificently adapted to the harsh climate of their habitat, in reduced numbers they represent a diminutive match for the powerful combination of drought and predation. As little as four inches of precipitation may fall in the Gobi in an entire year, and in years of exceptionally low rainfall, the remaining small groups of wild Bactrians are forced to return repeatedly to the same sources of water. Gathering around these oases are the camels’ primary predators, wolves, which lie in wait for easy kills. When the camels existed in large populations, such predatory behavior was less threatening. There was safety in large numbers.
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