Scientist Michelle Fournet and her colleagues from the University of New Hampshire hang out with humpback whales in Alaska, recording their daily communications - and then sending whale recordings back to the giant animals to see if and how they respond. Some of her latest findings could break new ground: she can identify individual whales by their sounds. Michelle tells us the moving story of how she morphed from broke actor to internationally-respected whale researcher - and how she hopes research on humpbacks' "language" can help humans protect them.

Four more have been murdered by a teen with an assault-style rifle - many more were injured - at Apalachee High School in Winder, GA. Still, this episode gives us a glimmer of hope: specialists in “behavioral threat assessment” have been quietly trying to spot potential killers for decades, in places from schools and companies to government agencies - and the latest carnage could probably have been avoided if authorities had followed their manual. Our guests, practitioners Monique Boudreaux and Matt Talbot, say everybody in America needs to help them instead of looking the other way.

Lee Bollinger, who was president of Columbia University and the University of Michigan, predicts that the number of black students at many colleges will plummet to low levels they haven't seen since the 60s and 70s. He says Chief Justice John Roberts and the other Republican extremists on the Court misinterpret the Constitution. And as for the belief that under affirmative action, college officials generally admitted blacks who weren't qualified? Lee says: Not true.