What would it be like to go inside the mind of an animal? We have all gazed into a creature's eyes and wondered: what is it thinking about? What does it really know? Now, the revolutionary science of animal cognition is revealing hard evidence about how animals understand the world around them, uncovering their remarkable problem-solving abilities and exploring the complexity of their powers of communication and even their emotions. In this mini-series, NOVA explores these breakthroughs through three iconic creatures: dogs, birds and dolphins. We'll travel into the spectacularly nuanced noses of dogs and wolves, and ask whether their reliance on different senses has shaped their evolution. We'll see through the eyes of a starling in flight and test the tool-using skills of the smartest of birds, the crow. We'll listen in as scientists track dolphins in the Caribbean and elephants on the African savannah, trying to unlock the secrets of animal communication. As we discover how researchers are pushing the animal mind to its limits, we'll uncover surprising similarities to -- and differences from -- the human mind. Today, researchers are discovering that some creatures have mastered skills purportedly restricted to humans. Many are bird brains. Meet a cockatoo with a talent for picking locks; a wild crow on a mission to solve an eight-step puzzle; and a tame raven who can solve a puzzle box so quickly that his performance has to be captured with high-speed photography. Are these skills really evidence of high intelligence or just parlor tricks, the result of training and instinct? To find out, NOVA tests the limits of some of the planet's brainiest animals, searching for the secrets of a problem-solving mind.