Despite their name, horseshoe crabs are not crabs but are related to arachnids (spiders, scorpions). Their scientific name Lunataspis aurora, means "crescent moon shield of the dawn." Few modern animals are as deserving of the title "living fossil" as the lowly horseshoe crab. Unchanged since before the Age of Dinosaurs, these creatures are literally living fossils. Today, marine shorelines worldwide are being threatened by human activity, and although some horseshoe crab populations are endangered, they have successfully weathered many previous crises, including the mass extinction that saw the demise of the dinosaurs and 95% of sea life 65 million years ago. The horseshoe crab survived!