Magnificent Migration
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THE MAGNIFICENT Land bridge 8 MY–14,500 Y MIGRATION Domestication of camels began between World camel population today About 6 million years ago, 3,000 and 4,000 years ago—slightly later than is about 30 million: 27 million of camelids began to move Best known today for horses—in both the Arabian Peninsula and these are dromedaries; 3 million westward across the land Camelini western Asia. are Bactrians; and only about that connected Asia and inhabiting hot, arid North America. 1,000 are Wild Bactrians. regions of North Africa and the Middle East, as well as colder steppes and Camelid ancestors deserts of Asia, the family Camelidae had its origins in North America. The The First Camels signature physical features The earliest-known camelids, the Protylopus and Lamini E the Poebrotherium, ranged in sizes comparable to of camels today—one or modern hares to goats. They appeared roughly 40 DMOR I SK million years ago in the North American savannah. two humps, wide padded U L Over the 20 million years that followed, more U L ; feet, well-protected eyes— O than a dozen other ancestral members of the T T O family Camelidae grew, developing larger bodies, . E may have developed K longer legs and long necks to better browse high C I The World's Most Adaptable Traveler? R ; vegetation. Some, like Megacamelus, grew even I as adaptations to North Camels have adapted to some of the Earth’s most demanding taller than the woolly mammoths in their time. LEWSK (Later, in the Middle East, the Syrian camel may American winters. environments. Both dromedaries and Bactrians can go days, even weeks, P About 300,000 now-feral A About 3 million Z without a drink of water. This is thanks to adaptations in its physiology, C have been even larger.) Around 25 million years dromedaries inhabit Australia’s years ago, J its circulatory and digestive systems, and its ability to let its body ago, two tribes of camelids divided: The Camelini Outback. They descend from AS camelids of the L temperature change more than any other mammal. These traits have camels imported from India O gradually migrated north and west, and the Lamini Lamini tribe CH I also helped camels keep a distance from predators. in the 19th century. N drifted south. entered South : T R America. O PP U S H Dromedary Circulation Eyes Nose Humps ARC E Bactrian Blood cells that can swell up to three Camels see well in both bright A camel can close its These store fat, not water. S E R times their normal size are what allow desert sun and at night. Their nostrils. This helps keep out The fat in the hump gives L A Wild Bactrian the camel to drink so much water. As it eyelids are semitranslucent, sand, and it also helps cool camels a reserve of energy N O I T uses water, the same cells narrow to keep which allows a camel to walk exhaled air, which helps when no vegetation is I Llama wing, allowing the camel to become with its eyes shut. Extra-long conserve water. available for grazing. ADD more dehydrated than other mammals. eyelashes, too, protect against Vicuna sand and dust. Guanaco Alpaca Dromedary (Camelus dromedarius) Bactrian (Camelus bactrianus) Camelops Megacamelus Aepycamelus Procamelus Poebrotherium Weight: 400–600 kilograms Weight: 600–1,000 kilograms 4 MY–10,000Y 10–5 MY 21–5 MY 22–5 MY 40–32 MY Shoulder height: 1.6–2 meters Shoulder height: 1.6–1.8 meters AramcoWorld November/December 2018 .