Scientists never stop asking. They're little kids who never grew up.

The observations that have developed over the years have given us perspective about where we fit in. We are newcomers, really recent arrivals on a planet that is four and a half billion years old.

When I was 12, we moved from New Jersey to Florida. The Gulf of Mexico was literally my backyard. Every day, I could see the ocean. At low tide I went out and played in seagrass meadows that used to come right up to the shore, filled with tiny seahorses, pipefish and soft corals. There was so much life! But then I witnessed the change, the loss of the shoreline, the loss of the mangrove trees, the loss of the seagrass meadows. Shallow bay areas were turned into parking lots.

Rather than be afraid of evolution and try to stifle inquiry, people should revel in the joys of knowing and find a serenity and a joy in being a part the rest of life on Earth. Not apart from it, but a part of it.

As a child, I was aware of the widely-held attitude that the ocean is so big, so resilient that we could use the sea as the ultimate place to dispose of anything we did not want, from garbage and nuclear wastes to sludge from sewage to entire ships that had reached the end of their useful life.

I find the lure of the unknown irresistible.

I've spent thousands of hours under water. And even in the deepest dive I have ever made, 2.5 miles (about 4 kilometers) down, I saw trash and other tangible evidence of our presence.