The Remora is a fish that lives with sharks, sea turtles and whales. The Latin name Remora means "holding back." This fish uses a sucking disc on top of its head to hitch a ride.

This type of relationship between animals is called "symbiosis," from the Greek word meaning "living together." The relationship is not parasitic because it is believed that both animals benefit. The Remora does not hurt the host; it acts as a cleaner fish, removing parasites from the host. It also detaches briefly when the shark attacks its prey, feasting on the scraps left over.

The remora is used by fishermen in some countries to catch other fish. They attach a line to the tail, release it and the remora swims off to attach itself to a large fish, enabling the fisherman to catch it. In ancient times, the Greeks and Romans believed remoras had magical powers. The Romans actually believed Emperor Caligula's death was due to remoras attached to his ship, holding it back and enabling enemy ships to attack it.