You may not give much thought to the regular bleeding of up to 500,000 Horseshoe Crabs a year. In fact, you may never have even heard of a Horseshoe Crab (or perhaps, mistaken it for a menu item). But as Popular Mechanics reports: “Every man, woman, and child and domestic animal on this planet that uses medical services is connected to the Horseshoe Crab … Components of this crab blood have a unique and invaluable talent for finding infection, and that has driven up an insatiable demand.”