Elephants are the only remaining family in their biological order. There are three living species of elephants. These are the Af

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问题     Elephants are the only remaining family in their biological order. There are three living species of elephants. These are the African bush and forest elephants and the Asia. Other species have been extinct since the last ice age.
    Elephants are the largest land mammals alive today. Their pregnancy period is 22 months. It is the longest of any land animal. At birth, it is common for an elephant calf to weigh 120 kg. An elephant may live as long as 70 years, and some even live longer. The largest elephant ever recorded was shot in Angola in 1956. It was male and weighed about 12, 000 kg. The smallest elephants were about the size of a calf or a large pig. They were a prehistoric variant that lived on the island of Crete. They existed until between 3000 BC and 5000 BC.
    Elephants are increasingly threatened by humans. Human-elephant conflicts are often deadly. They kill 150 elephants and up to 100 people per year in Asia. The African elephant population has gone from 3 million in 1970 to about 600, 000 in 1989. The numbers of this beast then dropped even further. By 2000 the number was down to 272, 000. In recent years, efforts to save these animals have helped it rise. The elephant is now protected around the world. Many restrictions have been enacted for their benefit, strictly limiting their capture and domestic use. Trade in products such as ivory is also controlled.
    Some scientists believe the elephant family is distantly related to sea cows. They also think there is a link between elephants and hyraxes. The fossil evidence does not offer certain proof while many believe the genetic evidence shows this. One theory suggests that these animals spent most of their time underwater. They would have used their trunks like snorkels for breathing. Modern elephants still have this ability, and they are known to swim like that. They can swim for up to 6 hours and 50 km.
Why do people around the world protect elephants?

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答案They are declining in numbers due to human’s killing.

解析 事实细节题。第三段第一句至第六句指出,大象因为人类的屠杀数量大减。第七句至第十句指出现在大象受到了保护。由此可知,因为大象数量的减少,人们开始对它们进行保护。
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