Kim Todd, an associate professor at Penn State Behrend and author of "Sparrow," was the latest guest on BirdCallsRadio, which originally aired Sunday, July 29, 2012. Listen as Kim describes the interesting history of the House Sparrow, its introduction to the United States and its impact on the native wildlife in the U.S.

Kim previously authored "Tinkering with Eden," a book about the introduction of exotic species to the U.S. ecology.