The remora receives more than a convenient food source; the sharks protect them from predators and give them free transportation throughout the oceans. Remoras keep the waters clear of scraps around the shark, preventing the development of unhealthy organisms near the shark.
How does the remora benefit the shark?
The remoras swim very close to the sharks, feeding off scraps of food dropped by the shark and also gaining some protection from predators. The remora removes parasites from the shark's skin and even inside the mouth, which benefits the shark.
Does the remora cause any harm to the shark?
These fish attach themselves to the larger marine creatures including sharks, turtles, manta rays and the like for an easy mode of transportation, to gain the protection provided by being one with the bigger animal, and for food. Yet their hitching on to a shark causes no harm to the shark itself.