Carl Safina

At one point, I didn't get out of bed for, I think, three months, and I went down to the bottom of the hill one day and I had to call somebody to get me to come back up - come pick me up because I couldn't physically walk up the hill.

Human activity is having a major impact on the planet. We consume or have diverted a large proportion of the productivity of the land and oceans. Our hunger for land crowds out fellow species. Our waste products pollute the waters, warm the atmosphere and acidify the oceans.