Whales are majestic, awe-inspiring animals. Some species can reach up to 150 tons and take in a livi

Whales are majestic, awe-inspiring animals. Some species can reach up to 150 tons and take in a living room-sized volume of water in one gulp. They can even dive thousands of feet into the ocean while holding their breath all the way down. But these traits are also why whales are a mystery to scientists. It’s hard to imagine that the earliest ancestors of these graceful creatures of the deep were four-legged dog-like animals that lived on land.

In his book Spying on Whales: The Past, Present, and Future of Earth’s Most Awesome Creatures, paleontologist Nick Pyenson examines the fascinating features of these animals—from their enormous size, echolocation abilities, and specialized feeding behaviors—and how they can be used to piece together the evolutionary story of whales. Tune in to today’s show at 2pm ET for our wrap up of Oceans Month!

Photo by Smithsonian Institution Archives/Public Domain