If you were to come across a horseshoe crab for the first time you might think so. With it’s tail that looks like a spear you would think it would use it for a weapon or that it might contain poison.

Actually, horseshoe crabs don’t use the tail as a weapon at all and there is no poison to be found here. The tail which is called a telson is just used to help it navigate and to turn itself back over should it get knocked onto it’s back.