A corollary development of increased efficiency in group defense is the narrowing of individual conformity. Predators counterrespond to social defensive mechanisms by watching for deviant individuals who, for reasons of health, inexperience, or whatever, fail to participate and, by failing, increase their vulnerability.---Furthermore there is abundant evidence that predators respond strongly to deviant individuals in the social groups they watch. Students of fish behaviour and ecology have observed that it is difficult to tag fish or to introduce distinctive mutants in the presence of predators. Predatory fish are stimulated by any change in appearance and attack altered individuals preferentially.
-E. O. Wilson: Sociobiology