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.
Please paraphrase the sentence "The fossil evidence does not offer certain proof while many believe the genetic evidence shows this".

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答案Ahhough many scientists.believe that elephants have a genetic relationship with sea cows or hyraxes,there is no fossil evidence to prove their belief.

解析 语义理解题。最后一段第一、二句指出一些科学家的观点,即大象与海象和蹄兔存在基因上的联系。第三句则指出,尽管许多人相信基因证据能够表明这一观点,但化石证据并未给予确切的证明。
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