A journey into the heartbeat of life on Earth. Millennia ago, when we first began puzzling over the mysteries of the human body, one organ stood out as vital. The heart was warm, it was central, and it moved as it pumped blood. The ancient Egyptians treated it with reverence, mummifying it separately from the body so that the soul inside it could be weighed. Aristotle believed that it was the seat of consciousness. Over the centuries, science has dispelled the myths, but our fascination with the heart has endured. From the origins of circulation, still evident in some microorganisms today, to the enormous hearts of blue whales, we journey with Bill to beaches where horseshoe crabs are being harvested for their life-saving blood, and under the sea to learn about the world's most natural antifreeze, flowing through the veins of icefish. And we follow him through human history, too, as scientists hypothesize wrongly and rightly about what is arguably our most important organ, ultimately developing the technologies that have helped us study the heart--and now, in the most cutting-edge labs, the tools that will help us regenerate it. Deeply researched and engagingly told, Pump is a fascinating natural history sure to be loved by readers of Mary Roach and Bill Bryson.