66.
C
A recent study of ancient and modern elephant 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 University when they were examing the genetic relationship between the ancient woolly mammoth and mastodon modern elephants—the Asian elepphant, African forest elephant, and African savanna elephant.
Once they obastain DNA sequences（序列）from two fossils（化石）,mammoths and mastodons, the team comparted them with DNA from modern elephants. They found their amazement that mordern 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 mamm oths. 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.
Previously, many naturalists believed that African savanna elephants and African forest elephants were two populationgs of the same species, despite the elephants’ significant size differences. The savanna elephant has an average shoulder height of 3.5 metres while the forest elephant has an averate shoulder double the weight of the forest elephant. But the fact that they look so differrent does not neccssarily mean they are different species. However the prooflay in the analysisi of the DNA.
Alfried Roca, assita nt professor in the Department of Animal Sciences at t he University of Illinois, said, “We now have to treat the forest and savanna elephants as two difficult units for conservation purpose. Since 1950, all Afican elephants have been conserved as one species. Now that we know the forest and savanna elephants have been distinct animals, the forest elephant should become a bigger priority（优先）for conservation purposes.”
One of the fossiles studied by the researchers is that of .
(A). the Asian elephant
(B). the forest elephant
(C). the savanna elephant
(D). the maslodon elephant
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