We couldn't go to the moon on whale oil. We don't have the capacity yet to consider doing such things as harnessing current sunlight. We're burning ancient sunlight in order to get us to where we now are. But it's costly.

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.

We humans have this idea that the ocean is so big, so vast, so resilient that it doesn't matter what we do to it. That may have been true 1,000 years ago. But in the last 100, especially the last 50 years, we have destroyed the assets that make our lives possible.

We must protect our ocean as if our lives depend upon it, because they do.

The Exxon Valdez spill triggered a swift and strong response that changed policies about shipping, about double-hulled construction. A number of laws came into place.

Fortunately, we know more about the problems that we have than in all preceding history. We know now the consequences of the things that we put into the air, into the water - of the way we treat life on Earth.

Ironically the very energy, the very basis of how we know what we know, has been reliant on having an energy source [necessary] to build rockets to go to the moon and Mars, to support airplanes that fly, and satellites to give us our communication.