By the end of the 20th century, up to 90 percent of the sharks, tuna, swordfish, marlins, groupers, turtles, whales, and many other large creatures that prospered in the Gulf for millions of years had been depleted by overfishing.

Humans have always wondered the big questions, "Who am I? Where have I come from? Where am I going?" It's part of human nature. It's perhaps the underpinnings of religion.

Fish from all over the world, from deep in the sea, wind up in countries from Germany to Japan. That is just crazy.

I've always said, 'Underwater or on top, men and women are compatible.'

Any astronaut can tell you you've got to do everything you can to learn about your life support system and then do everything you can to take care of it.

Places change over time with or without oil spills, but humans are responsible for the Deepwater Horizon gusher - and humans, as well as the corals, fish and other creatures, are suffering the consequences.

Ignorance is the biggest problem of all for the ocean - and for many other things as well.