Finding Fossils Along U.S. Freeways
Geologic pressures force ancient layers of rock above ground, exposing their cargo of fossils. Paleontologist Kirk Johnson and artist Ray Troll search the western United States for fossils and chronicle their finds in a new book, Cruisin' the Fossil Freeway.
Johnson and Troll speak with Andrea Seabrook.

Cruisin' the Fossil Freeway
An Epoch Tale of a Scientist and an Artist on the Ultimate 5,000-Mile Paleo Road Trip