There are currently three living species of elephants: the African Bush Elephant, the African Forest Elephant and the Asian Elephant or Indian Elephant. Other species such as the mammoths (猛犸象)  16  before the last ice age but are now  17  .

Elephants live in a structured social order.  18  females spend their entire lives in tight-knit family groups  19  mothers, daughters, sisters and aunts, males live mostly solitary lives. Elephants  20  live for 50 to 70 years. The elephant’s pregnant period is22months, the longest of  21  land animal. Newborn elephant calves weigh  22  260 pounds.

Elephants spend about 16 hours a day finding and eating food. Their diet consists  23  grasses, leaves, bamboo, twigs, bark, roots and small amounts of fruits, seeds and flowers. Interestingly, elephants only digest 40% of  24  they eat; an adult elephant can consume 300-600 lb of food a day.

Elephant skin is thick, grey and wrinkled. The wrinkles help elephants stay cool  25  water gets trapped inside the wrinkles and evaporates slowly. Their hearing is  26  and they can detect noise from miles away.

One of the most distinct  27  attributes of elephants is their tusks. Elephants use their tusks to dig for food, mark their  28  and perform other tasks. Elephants’ tusks are made of ivory. The  29  elephant ivory is one of the major reasons people hunt elephants and thus have significantly  30  the world’s elephant population. For this reason and many others, many people around the world are working hard to protect the species from further extinction.

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