States in the Great Lakes kill beavers and remove dams on select rivers and streams. They’re doing it, in part, for anglers and the multi-billion dollar fishing industry. But some people are not on board with that. Today’s episode is all about that conflict, and about how our scientific understanding of the role of beavers may be changing.

The author of "Ghetto Classics: How a youth orchestra changed a Nairobi slum" and one of the orchestra's founding members on starting a music program next to a garbage dump