Globally sharks have been killed for their fins, for their cartilage, for their livers, for their meat. But mostly what has driven some species of sharks to near extinction - including the hammerhead shark - is the new luxury taste for shark fin soup.

I have lots of heroes: anyone and everyone who does whatever they can to leave the natural world better than they found it.

I actually love diving at night; you see a lot of fish then that you don't see in the daytime.

When I write a scientific treatise, I might reach 100 people. When the 'National Geographic' covers a project, it communicates about plants and fish and underwater technology to more than 10 million people.

We don't have to be that greedy generation that just continued to take down the underpinnings of what makes the planet work in our favor.

It doesn't matter where on Earth you live, everyone is utterly dependent on the existence of that lovely, living saltwater soup. There's plenty of water in the universe without life, but nowhere is there life without water.

We have the power to abstain from destructive behavior.