By Brad Harrub, Ph.D.

Did you know there are dentist chairs in the ocean that fish can swim up to and get their teeth cleaned for free?

Yes, this is true!

These cleaning stations can be found throughout coral reefs. They are an example of a symbiotic relationship. Symbiotic relationships are when two species interact in a mutually beneficial way. In this case, the fish receive a free dental cleaning and the cleaning station gets food scraps that the fish leave behind. Both species benefit from the relationship.

These very real cleaning stations are areas that a fish can swim into and have parasites, bacteria, and dead skin removed from the skin, scales, gills and mouths of fish. The “cleaners” are gobies, blennies, wrasse fish, and shrimp that live in a concentrated area to provide cleaning services. The “clients,” are larger fish like grouper and sharks, which open their mouths to allow the cleaners to do their job.

In this symbiotic relationship, the fish gets a stress-free cleaning, while the small fish, shrimp and other organisms that live in the station get a meal. This mutually beneficial relationship is one of the many examples of how complex life forms interact with each other and their environment–a relationship not explained by evolution.