They also provide protection to the algae from predators. The relationship between coral and its zooxanthellae is very close. The coral control the release of photosynthates by the zooxanthellae and control population growth of the zooxanthellae. Some coral form less well-known mutualisms with some shrimp or crabs in which the crustaceans protect the corals from seastars and other coral predators and competitors. The coral feed the crustaceans by secreting a mucous on which the crustaceans feed.
Coral also provide shelter for the crustaceans.
Honeyguides are old-world birds that feed on insects and wax made by bees. When they find a beehive, especially one inaccessible to the birds without help, they will often go in search of a ratel or a human and lead the mammal to the hive. The mammal breaks into the hive and gets the honey. The damaged hive makes it easy for the honey guide to eat the bee larvae and wax. Other mutualisms Mutualisms abound.