Scientists thought they had a pretty good handle on the social interactions of bottlenose dophins (Tursiops). They’ve used the term fission-fusion dynamics to describe dolphin (and non-human primate) society and so far it has served researchers well. Fission-fusionsocieties among dolphins are characterized by two levels of social hierarchy: groups of two or three related males (“first-order alliances”) which work together to guard one or more females from other males, and larger teams comprised of several first-order alliances (“second-order alliances”) which cooperate to “steal” females from other groups. Since the individuals in first- and second-order alliances are related and therefore share genes, this sort of cooperation can be explained by kin selection.
