4/14/97

As is the case with any large society, groups of social outcasts (or those who have such a low self-esteem that they consider themselves social outcasts) form "gangs" as a means of self protection and as a source of love that they cannot otherwise receive from what is considered "normal" society. In the case of squirrel gangs, many members were exiled from squirrel society for not participating in or failing to pass (but surviving) a hazing ritual.

Just being an outcast isn't enough to be accepted into a gang. All would-be members are forced to undergo a hazing-style test of loyalty and endurance (as you pointed out, "it appears obvious that fraternal brotherhood between squirrels is not just to soothe the mind of the troubled squirrel, but to ensure survival of the species..."). These tests often resemble traditional squirrel hazing rituals, with the exception that there are no observers: everyone must be involved. This probably goes towards testing the chemistry between individual members.