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.

We woke up some years ago about the consequences of ozone depletion, the hole in the atmosphere. You can't see it. You can't taste it. You can't smell it. But now we do regard that as a key issue. It's a scientific finding.

Not only who am I, but who are we? And where are we going? It's the "we." It's the social connections that are special to human beings.

If Darwin could see what we now see, what we now know about the ocean, about the atmosphere, about the nature of life, as we now understand it, about the importance of microbes - I think he would just beam with joy that many of the thoughts and the glimpses of the majesty of life on Earth that he had during his life, now magnified many times over.

People I know who succeed don't mind working. Those who are competent seem to like doing things well -- not stopping because they haven't accomplished what they wanted to on the first go-round. They're willing to do it twenty times, if necessary. There's an illusion that the good people can easily do something, and it's not necessarily true. They're just determined to do it right. I was impressed by hearing one of the women at Radcliffe talk about writing a poem, how many revisions a single poem sometimes has to go through -- fifty or sixty revisions to come out with a poem sixteen lines long.

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.

The image of Earth from space transformed our view of ourselves. It is maybe the most important image that exists - because we can see ourselves in context in a way that otherwise would be really hard to explain. It should inspire us to wonder about it, to want to know everything we can about it and do everything we can to take care of it.