Animals

Everything is adapted for life on the desert. Feet are broadened to walk on sand. Eyelashes protect eyes from wind-blown sand. Nostrils close to keep sand out. Lips are thickened to withstand the coarsest of desert plants. Coloration matches the environment. Callouses are present on knees and other parts of the body that touch the hot sand when the animal sits down. Hump is a flesh mound not supported by bones. A reserve of fat (not water) is stored in the hump. Hump size varies with food supply and working conditions. Can tolerate a rise in temperature of 12 degrees Fahrenheit. Able to drink brackish or salt water. Camels exhibit unusual tolerance for dehydration. Most animals perish when 20% of their body weight is lost whereas camels survive a 40% loss of body weight without serious consequences. Heavy fur and the fatty hump serve to insulate the body, preventing body temperature from rising to the sweating point (the major cause of water loss). When water again becomes available, camels are able to restore their body water quickly; they have been known to drink one third of their body weight in 10 minutes.