Plasticity in Symbiotic Behavior: As Demonstrated by a Gobiid Fish (Amblyeleotris steinitzi) Associated with Alpheid Shrimps

Animal behavior should be invariant as long as the innate mechanisms do not change. Some behavior regulations are thought to be programmed by means of mixed strategy or learning by instinct. Such ideas assume however the occurrence of a unique identification of the surroundings by the animal, thus, external perturbation may contradict expectation. The modification of the symbiotic behavior of the goby Amblyeleotris steinitzi, associated with several species of alpheid shrimps, is reported in an experimental environment.