In the late nineteenth century, Americans caught bicycle fever. Evan Friss is the author of The Cycling City, about the 1890s when American cities were home to more cyclists than anywhere else in the world. Plus: Veteran animator “Tuck” Tucker talks about illustrating many of the most popular cartoons in recent times, including SpongeBob Squarepants, Hey Arnold!, Family Guy, and The Simpsons. Also: The NCAA has doled out more academic sanctions to historically black colleges and universities than to other institutions. Carray Banks hopes to make college sports more equitable.

Later in the show: There’s a scene in the 1987 film Dirty Dancing where a dance instructor lifts his young student in a beautiful lake at sunset. Today, that lake is disappearing, and Skip Watts and George Stephenson are studying why. And: Virginia’s shoreline is expecting a sea level rise of as much as three feet or more by 2060. Ray Toll is leading a comprehensive local response to the flooding that will be used as a model for the rest of the nation. Plus: The earliest environmentalists weren’t tree-huggers; they were hunters and colonialists. Historian Stephen Macekura traces how African conservation has been closely tied with colonialism and development.