Mammals of the Sea的意思|示意

Since there is such an abundance of food in the sea, it is understandable that some of the efficient, highly adaptable, warm-blooded mammals that evolved on land should have returned to the sea.

海洋哺乳动物既然海洋中有如此丰富的食物，一些原本在陆地生存的高效率的，适应性强的暖血型动物返回海洋生存是不难理解的。

You might think, therefore, that modem land tortoises have probably stayed on land ever since those early terrestrial times, as most mammals did after a few of them went back to the sea.

因此，你可能会想，现代陆龟可能从早期的陆栖时代就一直呆在陆地上，就像大多数哺乳动物，他们中的一些返回海洋之后所做的那样。

But the slow-breeding mammals of the sea have been all but wiped out by humans seeking to satisfy their wants and whims.

但繁衍迟钝的陆地哺乳动物却因为有了同心专心只想满意一已私欲的人类而濒临。

So, it probably is the orcas that are causing the decline of all the smaller sea mammals mentioned in the passage - the seals, the sea lions, and the sea otters.

所以，很可能是逆戟鲸的捕食导致了文中提到的诸如海豹、海狮和海獭等小型哺乳动物的数量减少。

The Arctic mammals, known as "sea unicorns" thanks to their single long tusks, also transmitted measurements for the winter layer of surface water that shields sea ice from the warmer waters below.

这种因为长着一根长牙而被称为“海洋独角兽”的北冰洋哺乳动物，同时还传输冬季海水表面的温度，这层海水将海面冰层和下面温暖的海水隔离开来。

At sea, as on land, humans have now positioned themselves on the top of the whole great pyramid of life, and they have caused serious problems for the mammals of the sea.

在陆地和海洋，人类都已处在巨大的生物金字塔的最顶端，成为所有生物的主宰，并给海洋哺乳动物带来巨大的危胁。