Horseshoe crabs have ten eyes, five pairs of walking legs, a heart half the length of their bodies, and blood that may one day save your life. They have been on this planet for 445 million years—since long before the dinosaurs arrived. They have been used as fertilizer and as bait, their eggs are a critical food for migratory birds, and their blood is a major component in tests for medical contamination. Join science writer Anthony D. Fredericks as he travels from the Delaware Bay to the Florida Panhandle on a quest through the natural history and science behind one of nature’s oldest and oddest survivors.

“A Fascinating, relevant, revealing, and endlessly enjoyable book.” —Richard Ellis, author of The Great Sperm Whale and Tuna

“A reminder that a skillful storyteller can find a good tale anywhere.” —Peter Laufer, author of The Dangerous World of Butterflies

“An accurate and very readable introduction to Limulus polyphemus. I highly recommend it.” —Carl N. Shuster, Jr., The College of William and Mary

“An accessible, playful introduction to an ancient animal that continues to amaze us.” —Michael Oates, video documentarian

“An entertaining guide to a creature that’s 445 million years old and still having sex on the beach.” —Richard Conniff, author of The Species Seekers and Spineless Wonders