One Hump or Two?

A camel is an even-toed ungulate, which means it walks on 2 toes on each foot. They also have distinctive fatty deposits (humps) on the back. The Dromedary (94% of the world’s camel population) has 1 hump. The Bactrian camel (6% of the camel population) has 2 humps. The Wild Bactrian camel is a 3rd species and at less than 1% of the camel population, it is critically endangered. All of these camels are suited to a desert habitat. Except for the Wild Bactrian, camels have been domesticated for a long time, and have been a vital means of transport for passengers and cargo. As domesticated animals, they also provide food, such as milk and meat, and textiles via fiber and felt from hair.

 Sometimes the word camel is used in a wider sense, to include not only the Old World camels but also New World camelids (llama, alpaca, quanaco and the vicuna). These new world animals are technically camelids, not camels.

 Camels live an average of 40-50 years. An adult dromedary camel stands 6’1” at the shoulder and 7’1” at the hump, while Bactrian camels can be a foot taller. Camels can run in short bursts at 40 mph, and at a sustained speed of 25 mph. Dromedaries weight as much as 1,320 lbs, while Bactrians can get up to 2,200 lbs.

 The earliest known camel is called Protylopus and lived in North America 40 - 50 million years ago. It was about the size of a rabbit and lived in the open woodlands of what is now South Dakota. By 35 million years ago, it was the size of a goat and had many more traits similar to camels and llamas. Other ancient forms of camels or camelids were the Stenomylius and the long-necked Aepycamelus.

 The direct ancestor of modern camels (and perhaps of New World camelids as well) was Paracamelius, which existed 3 - 5 million years ago. It spread to South America via the Isthmus of Panama, and to the ‘Old World’ via the Bering Land Bridge. There have been surprising finds of fossil Paracamelius on Ellesmere Island (very much north of Canada and barely west of Greenland) which indicate the dromedary is descended from a larger, boreal browser whose hump may have evolved as an adaptation in a cold climate. This particular creature is estimated to have stood around 9 feet tall.

 Which just goes to show that given enough time, evolution can completely adapt to an environment that otherwise would kill the original animal.

  

https://en.wikipedia.org/wiki/Camel