BlueRidgeKitties/Flickr (Creative Commons licensed)
File photo: Sharks swimming overhead - seen from the Ocean Voyager tunnel at the Georgia Aquarium.
Sharks have been swimming in our planet's waters for hundreds of millions of years. They even predate dinosaurs. Despite that, little is known about them - where they swim and how they mate, for instance. Hard data might be lacking but that hasn't stopped humans from developing a deeply negative attitude towards sharks. That relationship is the topic of a new book, called "Demon Fish," by Washington Post journalist Juliet Eilperin who joins Madeleine.