Seahorses are the only fish to have prehensile tails. The seahorse uses the prehensile tail to anchor itself to the sea floor, using it to latch on to sea grass and coral during water turbulence and while eating, according to National Geographic. AskNature.org reports that the prehensile tail exhibits both strength and flexibility due to the seahorse's muscle structure and the rigidity of its dermal plates.
Because of their equine body shape, seahorses are terrible swimmers, using only a small fin on the back to move and two small pectoral fins near the head to steer. The prehensile tail allows the seahorse to survive by giving it an anchor. If a seahorse was forced to attempt to swim through the currents created by a storm, the seahorse could die from exhaustion. The seahorse has no teeth and no stomach, resulting in a need to eat almost constantly in order to live. By using its prehensile tail to anchor itself to the sea floor, the seahorse can feed constantly on the plankton and small crustaceans that float by. Seahorses eat by sucking food in through their snouts. Seahorses are also rare because they mate for life and the males carry unborn offspring.