A QUANTITATIVE-ANALYSIS OF AGONISTIC BEHAVIOR IN JUVENILE AMERICAN LOBSTERS (HOMARUS AMERICANUSL)

In these studies a quantitative analysis of agonistic (fighting) behav ior in lobsters in presented as a first step in our attempt to relate patterns of behavior to under-lying neurobiological mechanisms. The ag onistic behavior of juvenille American lobsters (Homarus americanus L. ) was studied in laboratory tanks at the New England Aquarium. Using v ideo analyses and statistical techniques: (1) an ethogram of agonistic behavior was constructed; and (2) the temporal structure of the behav ior was identified. We demonstrated that fighting in juvenile lobsters proceeds according to strict rules of conduct. All animals exhibit si x common behavioral patterns in a stereotypical manner. a temporal seq uence of these patterns was evident, representing an increase in inten sity during confrontations. the typical scenario of an encounter begin s with extensive threat displays upon first contact, continues with pe riods of ritualized aggression and restrained use of the claws, and te rminates in a brief session of unrestrained combat. Predictions of gam e theory (i.e assessment strategies) provide a useful framework for th e understanding of fighting in lobsters. The presence of a highly stru ctured behavioral system may reduce the potential for damage in fights among conspecifics, and may prove useful in attempts to study the neu robiological causes of complex behavioral patterns such as aggression.