What does your dog really think about you? To find out, Gregory Berns became the first neuroscientist to persuade dogs to lie in an MRI machine wide awake. Now we know more about our best friends than ever before - how varying capacities for self-control and different value systems set them apart as individuals, and how deeply they understand the words we speak to them. Berns' discoveries have profound implications for how we communicate with and treat these beloved animals. But he didn't stop there. Berns also delves into the inner lives of sea lions, bats, dolphins, and even the extinct Tasmanian tiger. His revolutionary explorations are essential reading for animal lovers of all stripes.