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湖北黄冈市2017高考英语阅读理解精练（11）及（解析）答案 阅读下列四篇短文，从每小题后所给的A,B,C或D四个选项中，选出最佳选项。 A recent study of ancient and modern elephants has come up with the unexpected conclusion that the African elephant is divided into two distinct (不同的) species. The discovery was made by researchers at York and Harvard Universities when they were examining the genetic relationship between the ancient woolly mammoth and mastodon to modern elephants—the Asian elephant, African forest elephant, and African savanna elephant. Once they obtained DNA sequences (序列) from two fossils (化石), mammoths and mastodons, the team compared them with DNA from modern elephants. They found to their amazement that modern forest and savanna elephants are as distinct from each other as Asian elephants and mammoths. The scientists used detailed genetic analysis to prove that the African savanna elephant and the African forest elephant have been distinct species for several million years. The divergence of the two species took place around the time of the divergence of Asian elephants and woolly mammoths. This result amazed all the scientists. There has long been debate in the scientific community that the two might be separate species, but this is the most convincing scientific evidence so far that they are indeed different species. | 
