The colossal plants and animals of our world—dinosaurs, whales, and even trees—are a source of unending fascination, and their sheer scale can be truly impressive. Size is integral to the way that organisms experience the world: a puddle that a human being would step over without thinking is an entire world to thousands of microscopic rotifers. But why aren't bugs the size of elephants, or whales the size of goldfish? In this lavishly illustrated book, biologist Graeme Ruxton offers a diverse array of examples, from huge butterflies to giant squid, and explains the often unexpected physics, biology, and evolutionary drivers behind organism size.

"Packed with glossy photos of stomping dinosaurs, belly-flopping whales, colossal squid and even prodigious pumpkins…. Ruxton has created a menagerie of modern organisms that will make any reader do a double-take."—Wall Street Journal