Symbiosis is a close and long-term interaction between two different species of organisms. The anemone (i.e. Calliactis parasitica) lives on the shell of the hermit crab (Dardanus calidus). The relationship between these two species is mutualism i.e. the sea anemone benefited from the thrown-up food by the hermit crab and in turn, the sea anemone protects the hermit crab with its stings.