the wrack line and think you might see a horseshoe crab that is still alive and struggling, you should pick them up by their sides and right them up so they can get back to the sea. This simple act can save many crabs. Horseshoe crabs have also become essential in the medical field as their special blue blood (containing copper instead of iron) will congeal in the presence of either living or dead gram negative bacteria (both are undesirable). This is another adaptation which has made the horseshoe crab survive through the centuries. Opposite page: Horseshoe crabs mating, This page (clockwise): Horseshoe crab blood being drained, child examing horseshoe crab molt, horseshoe crab molting Image (c): beachchairscientist.com, wired.com, beachchairscientist.com, deseagrant.org
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