It has been said--tongue in cheek--that animals were invented by water as a device for transporting itself from one place to another. That’s an interesting perspective, especially considering that when animals left the seas in which life arose, they took saltwater with them, in their bodies--an internal environment crucial for cellular survival. We are, in a sense, soft vessels of seawater. Seventy percent of our bodies is water, the same percentage that covers Earth’s surface. We are wrapped around an ocean within. You can test this simply enough:
Taste your tears.

--Carl Safina, from the book Song for the Blue Ocean, reprinted by arrangement with Henry Holt & Co., all rights reserved