No Assholes Rule

Biological Parallel

Vampire bat colonies sustain life-or-death reciprocal blood sharing among 8-12 individuals—but bats who receive without reciprocating get permanently ostracized, even starving. The colony cannot afford defectors who poison cooperation: one 'asshole bat' undermines the trust network that keeps everyone alive between feedings. Robert Sutton's rule mirrors this biological intolerance: high-performing groups cannot tolerate brilliant jerks because cooperation scales quadratically with trust, and toxicity metastasizes faster than talent compensates.