Gavrilets and colleagues identified conditions under which alliances can emerge in the group: increasing group size, growing awareness of ongoing conflicts, better abilities in attracting allies and building complex coalitions, and better memories of past events.
Most interestingly, the model shows that the shift from a group with no alliances to one or more alliances typically occurs suddenly, within several generations, in a phase-transition like fashion. Even more surprisingly, under certain conditions (which include some cultural inheritance of social networks) a single alliance comprising all members of the group can emerge in which resources are divided evenly. That is, the competition among non-equal individuals can paradoxically result in their eventual equality.
Gavrilets and colleagues argue that such an "egalitarian revolution" could also follow a change in the mating system that would increase father-son social bonds or an increase in fidelity of cultural inheritance of social networks. Interestingly, the fact that mother-daughter social bonds are often very strong in apes suggests (everything else being the same) that females could more easily achieve egalitarian societies.
The model also highlights the importance of the presence of outsiders (or "scapegoats") for stability of small alliances. The researchers s
|Contact: Sergey Gavrilets|
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