Functional Anatomical Adaptations of Dromedary (Camelus Dromedaries) and Ecological Evolutionary Impacts in KSA

Abstract

The dromedary (Camelus dromedaries), also called Arabian camel or one humped camel, was domesticated in the Arabian Peninsula. About one million camels live in KSA with significant economic, social and ecological importance. It is able to survive in hot dry desert due to anatomical structure and its ecological adaptations. Camel has long double eyelashes and a nictitating eye membrane to protect the eyes from the sun and sand. It also has closable nostrils. It breathes slowly with no panting. The lips are thick to help the camel eat the prickly shrubs. There is a thick coat of hair even inside the camel's ear .In KSA four subtypes of dromedary are known by different skin colors. Its hump is for storage of fat which is metabolized to provide energy and water. The legs are long and thin with thick covers on knees. Hooves have a broad, flat leathery pad. Camel body temperature keeps fluctuating from 34°C to 41.7°C (93°F-107°F.). This helps the animal sweat less. The red blood cells of camels are small and oval in shape to let the flow of blood continue even in a dehydrated state and to prevent them from rupturing due to osmosis. Its kidneys are capable of concentrating urine markedly to reduce water loss. There is normal blood glucose which after ten days of water deprivation increases from 20 to 80% without glucosuria. An extremely long large intestine absorbs every last drop of water from the digested foods. Scientists believe that ancestors of the modern camel lived in North America at least 40 million years ago and migrated to Asia. All camels have 74 chromosomes with a very similar morphology. Three Pleistocene camel fossil localities were discovered in the southwestern part of the An Nafud sand sea (northern Saudi Arabia). The Arabian camel genome is the first mammalian genome to be sequenced in the Middle East. The findings suggested the possibility of camel-specific evolution to adapt to desert environments