There is more unknown than known when it comes to this giant aquatic mammal.

每当提起这种巨大的水栖哺乳动物，未知的总是比已知的多。

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In China, conservation efforts have already failed to protect the Yangtze River dolphin, the first large aquatic mammal to go extinct since the Caribbean monk seal in the 1950s.

在中国，保护白鳍豚免于灭绝的努力已经失败。白鳍豚是继上世纪50年代加勒比僧海豹之后，首个灭绝的大型水生哺乳动物。

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Also called duckbill semi aquatic egg-laying mammal native to Tasmania and southern and eastern Australia.

鸭嘴兽是半水栖卵生哺乳动物，原产于塔斯马尼亚岛和澳洲地窍部及东部。

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The aquatic mammal was taken to Edinburgh Zoo for a proper health check and DNA testing, before being released back into the reserve.

BBC: Beaver

She said the animal science building would include aquatic, reptile and mammal rooms, a laboratory and six teaching classrooms.

BBC: Dorset colleges receive government renovation grants