A Southern right whale breach in El Doradillo Beach, Patagonia, Argentina. Scientists watching for baby right whales off the Southeast U.S. coast have yet to spot a single newborn seven weeks into the endangered species' calving season , a dry spell researchers haven't seen in nearly 30 years. Maxi Jonas/AP Photo

The World Of Whales

Whales can weigh up to 300,000 pounds and live for 200 years or more. Nick Pyenson is the curator of fossil marine mammals at the Smithsonian Institution’s National Museum of Natural History in Washington. He joins us to talk about how whales evolved from land-roaming creatures – and about their prospects for survival in a warming world. His new book is called “Spying On Whales: The Past, Present, And Future of Earth’s Most Awesome Creatures” (Viking).