Sirenians, or sea cows, are a particular group of mammals that superficially resembles whales in having, amongst other features, a streamlined-body and horizontal tail fluke. Though belonging to the so-called marine mammals, such as whales and seals, sea cows are members of a group having a single origin that includes their closest living relatives, the proboscideans (or elephants in the broader sense).
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Killing a name of an extinct sea cow species