David Choate (Underwater Archaeologist, 31)
I think about it every time I come to the surface: how lucky I am. I've been diving since I was 14, and got a master's in archaeological management, so diving for the National Park Service is the perfect combination. Nearly half of the parks have submerged land. Our team of five divers documents sites—protecting against looting or developing interpretive plans for the public. There are lots of things you wouldn't expect underwater: Anasazi ruins. A B-29 bomber. Our work is not easy. We spend long days in muddy or even contaminated waters. Up to a third of my year is at dive sites. The rest is research. This summer, I'm investigating a Spanish galleon off Point Reyes in a great white shark area. Sure beats selling insurance.