However, the amount of oxygen available to cells, tissues and animals themselves can vary greatly.

然而，细胞、组织和动物本身所能获得的氧气量可能在很大差异。

Warmer oceans hold less available oxygen, but as body temperature increases in animals, their metabolism increases and they actually require more oxygen.

温暖的海洋容纳了更少的可用氧气，但动物的体温增加也使得牠们的新陈代谢率增加，让牠们实际上需要更多的氧气。

There, creatures odd and tasty have learned to survive in constant darkness, near-freezing cold, and extreme pressure, all of which mean there's very little available oxygen, food, or companionship.

海洋深处的生物奇特而有趣，它们会学习怎样在充满黑暗的环境和接近零度的气温和极端的压力下生存，即意味着这里有非常稀缺的氧气、食物或朋友。