horseshoe crab

The strange anatomy of the horseshoe crab is one of this animal's most notable aspects. Unfortunately, the long, thin, spike-like tail of horseshoe crabs has given this species an unfavorable reputation. Many people view horseshoe crabs as dangerous animals because they have sharp tails. In reality, horseshoe crabs are harmless. Their tails are used primarily to flip themselves upright if they are accidentally overturned.