The horseshoe crab has roamed Earths sands and shallow waters for 500 million years. These living fossils have special body parts, mating habits, and survival instincts that have kept the species alive since prehistoric times. Readers will learn all about these special arthropods through age-appropriate, science-heavy text. Additional learning opportunities come in the form of full-color photographs, diagrams, fact boxes, a glossary, and an index, which all play a part in keeping readers engaged and informed.