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Horseshoe Crab
Ever wondered what kinds of animals have been walking the Earth before the dinosaurs first appeared? Well, this is what some of them looked like. These incredible survivors are 540 million years old and have successfully outlived some of the more menacing and aggressive species. Maybe it was the fierce-looking shell that has protected them for millions of years, or maybe it were the 5 pairs of eyes they have. Two of them you can actually see poking from the shell. Horseshoe crabs are related to the more ancient trilobites that once inhabited our planet. Their blood is even used for testing vaccines and drugs.
