Which makes sense, because many large sharks today are mesothermic – they can keep their bodies a little warmer than the surrounding water temperature, which helps them stay active even in colder waters.

这很有道理，因为今天许多大型鲨鱼都是中温性的——它们能够保持身体的温度比周围水温略高，这帮助它们即使在冷水中也能保持活跃。

We tend to think of endothermic and exothermic animals as two sides of a coin, as if you're one or the other.

我们喜欢把内温性和外温性看成硬币的两面，似乎你必须是两。

All reptiles are ectothermic, so they need heat from an outside source to stay warm.

所有爬行动物都是外温性的，所以它们需要从外部来源获取热量来保持体温。