The coastal hypothesis suggests an economy based on marine mammal hunting, saltwater fishing gathering, and the use of watercraft.(沿海假说提出了一种以捕猎海洋哺乳动物、收集捕捞咸水鱼和使用船只为基础的经济模式。)
The only clear explanation is that humans caused the extinction of the various mammal species through excessive hunting.(唯一明确的解释是人类的过度捕猎导致了各种哺乳动物的灭绝。)
The elephant is the only mammal that can't jump.(大象是唯一一种不会跳的哺乳类动物。)
Because fish look through water, their eyes are very different from a mammal.(因为鱼能透过水看东西，它们的眼睛与哺乳动物非常不同。)
Here is a mammal.(这是一只哺乳动物。)
That's like comparing a modern mammal to a dinosaur.(这就好比拿现代哺乳类动物和恐龙相比较一样。)
Bats is the only mammal that can fly.(蝙蝠是唯一能飞的哺乳动物。)
Like when you walk outside on a hot day, you perspire, and your body cools itself down, a classic example of how a mammal regulates its own body temperature.(比如，当你在炎热的天气在户外行走，你会出汗，你的身体会自我降温，这是哺乳动物如何调节自身体温的典型例子。)
I mean, Ambulocetus is a mammal that shows a sort of bridge between walking on land and swimming.(我的意思是，陆行鲸是一种哺乳动物，可以指明一个路上行走动物和水中游泳动物的清晰联系。)
