Catalyst: Wildlife migration corridors

Biologists install digital cameras and microphones around wild habitats to observe where endangered animals migrate. By mapping wildlife movements conservationists can advise governments how to build infrastructure that protects biodiversity.

WATCH: See more from season 2 of “Catalyst”

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Catalyst: Acoustic Ecology Lab

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Andy Martinez

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Finding Your Roots “The New World”

Henry Louis Gates, Jr. traces the ancestors of actor John Lithgow and journalist Maria Hinojosa who thrived in North America before the birth of the U.S.

'Atlantic Crossing' on Masterpiece

Atlantic Crossing

A princess steals the president's heart in this drama based on the relationship of Franklin Roosevelt and Norwegian Crown Princess Martha.

Independent Lens: Philly D.A. Part One and Two

Go inside the emotional, high-stakes work that Philadelphia District Attorney Larry Krasner and an ensemble of outsiders from different walks of life as they attempt an overhaul of an entrenched criminal justice system.