The Earth Moved: On the Remarkable Achievements of Earthworms

To most people, worms may be nothing more than things to avoid on the sidewalk after a summer shower. But earthworms do much more than that: they plow the soil, fight diseases, and make fertile land out of ordinary dirt. Today's guest on Focus, writer Amy Stewart, takes us underground to investigate the numerous different species of this creature and how they contribute to the health of our planet and population.

Guest: Amy Stewart (speaker, artist; author of The Earth Moved: On the Remarkable Achievements of Earthworms).