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A camel is an even-toed ungulate within the genus Camelus,bearing distinctive fatty deposits known as humps on its back.There are two species of camels:the dromedary or Arabian camel has a single hump,and the Bactrian camel has two humps.They are native to the dry desert areas of West Asia,and Central and East Asia,respectively.Both species are domesticated to provide milk and meat,and as beasts of burden.
The term camel,(from the Arabic جمل,derived from the triconsonantal root signifying "beauty"),is also used more broadly to describe any of the six camel-like creatures in the family Camelidae:the two true camels,and the four South American camelids,the llama,alpaca,guanaco,and vicuña.
The average life expectancy of a camel is 40 to 50 years.A fully grown adult camel stands 1.85 m (6 ft 1 in) at the shoulder and 2.15 m (7 ft 1 in) at the hump.The hump rises about 30 inches (76.20 cm) out of its body.Camels can run at up to 65 km/h (40 mph) in short bursts and sustain speeds of up to 40 km/h (25 mph).
Fossil evidence indicates that the ancestors of modern camels evolved in North America during the Palaeogene period (see also Camelops),and later spread to most parts of Asia.Humans first domesticated camels well before 2000 BC.[1][2]
骆驼是骆驼科骆驼属的动物,只有两种,鼻孔能开闭,足有肉垫厚皮,适合在沙漠中行走,背有肉峰,内蓄脂肪,胃有三室,第一胃室有20-30个水脬,可以贮水,红血球可以大幅膨胀吸水来贮水,所以耐饥渴,可以多日不吃不喝,一旦遇到水草,可以大量饮水贮存.所以被称为“沙漠之舟”.生活在沙漠边缘的人类早在公元前3000年已经开始驯养骆驼,作为役畜,以供驮运和骑乘,有许多国家有倚赖骆驼为生的骆驼牧民,甚至有骆驼骑兵.
单峰骆驼毛短,主要生活在北非洲和西亚洲、印度等热带地域,生活在沙漠地带的牧民以骆驼奶甚至骆驼血作为食物,目前全世界只有1400万头,全部是家畜.19世纪末澳大利亚曾从非洲引进部分单峰骆驼,后来由于不再应用役畜,只向中东出口,大约有3200头散落到澳大利亚沙漠重新野化.