CAMELS

Camels are land mammals that belong to the order Artiodacytla and the family Camelidae. Camels originated in North America during the late Eocene and were restricted to that continent until the end of the Miocene. They earliest camels were rabbit sized. During the Oligocene to early Miocene time, they spread to open woodlands in places like South Dakota and reached goat size. During the Miocene, camels expanded into steppe and grasslands in North America. In order to be able to eat/grind coarse, gritty grass, camels developed high-crowned cheek teeth. Their necks and legs lengthened. Some species were llama-size, and other species began to resemble modern-day camels and giraffes.

Procamelus of late Miocene age (modified after Savage and Long, p. 217). Procamelus has very distinctive splayed feet.

Pliocene-age camels were biologically diverse (with eight different forms of camels)a in southern California (Ana-Borrego Park area). Also during Pliocene time, camels migrated for the first time into Asia, Europe, and Africa.

During the early Pleistocene, giant forms of camels evolved. The largest was Titantylops, which was 3.5 m at the shoulder. It lived in Nebraska. Also during this time, camels reached South America, where they evolved into the llama, alpaca, guanaco, and vicuña.

Skeleton of Titanotylopus nebraskensis on display at the Los Angeles County Museum of Natural History—Fossil Mammal Room.

The remains of the camel Camelops, a close relative of the llama, are found in the late Pleistocene Rancho La Brea tar deposits in Los Angeles, California. This camel went extinct about 11,000 years ago.

Side and top views of a camel tooth (2.75 in high, 1 in wide) from Rancho La Brea. 

Camels surviving today as the “camel” and dromedary. The “camel,” also known as the Bacrtrin has two humps (a sort of deposit of fatty tissue) and lives in the Gobi Desert of Mongolia. During the winter, Bactrins have long shaggy hair for protection from the cold weather. The dromedary has a single hump and lives in Africa and the Middle East. Domedaries have longer legs and shorter hair in comparison to the two-hump camels. They also have shorter tempers.

There are feral (escaped from captivity) camels in Australia today. 

Key references:

Jefferson, G.T. and L. Lindsay. 2006 Fossil treasures of the Anza-Borrego Desert. The  last seven million years. Sunbelt Publications. 394 pp.

Savage, R.J.C. and M.R. Long. 1986. Mammal evoution an illustrated guide. British Museum (Natural History). 299 pp.