Warum wollen Menschen soviel Gleichheit?

Ein Modell zur evolutionären Entwicklung des Wunsches nach Gleichheit wird in diesem Artikel (PNAS) besprochen:

The evolutionary emergence of the egalitarian syndrome is one of the most intriguing unsolved puzzles related to the origins of modern humans. Standard explanations and models for cooperation and altruism—reciprocity, kin and group selection, and punishment— are not directly applicable to the emergence of egalitarian behavior in hierarchically organized groups that characterized the social life of our ancestors. Here I study an evolutionary model of groupliving individuals competing for resources and reproductive success. In the model, the differences in fighting abilities lead to the emergence of hierarchies where stronger individuals take away resources from weaker individuals and, as a result, have higher reproductive success. First, I show that the logic of within-group competition implies under rather general conditions that each individual benefits if the transfer of the resource from a weaker group member to a stronger one is prevented. This effect is especially strong in small groups. Then I demonstrate that this effect can result in the evolution of a particular, genetically controlled psychology causing individuals to interfere in a bully–victim conflict on the side of the victim. A necessary condition is a high efficiency of coalitions in conflicts against the bullies. The egalitarian drive leads to a dramatic reduction in within-group inequality. Simultaneously it creates the conditions for the emergence of inequity aversion, empathy, compassion, and egalitarian moral values via the internalization of behavioral rules imposed by natural selection. It also promotes widespread cooperation via coalition formation.

Quelle:  On the evolutionary origins of the egalitarian syndrome

Der Wunsch nach Gleichheit soll also letztendlich ein evolutionär entwickeltes Gruppenverhalten sein, dass dem Individuum Vorteile absichert. Im Gegensatz zu einer kulturellen Entwicklung, bei der wir uns über die egoistische Natur erheben und eine darüber hinaus gehende Moral entwickeln.

Dazu heißt es in dem Artikel:

The origins of moral values have intrigued scholars for millennia. Darwin saw human morality as derived from animal “social instincts” (59) that transform to a “moral sense or conscience as soon as . . . intellectual powers become . . . well developed” (ref. 59, p. 8). In a modern perspective, viewing human conscience as a mere by-product of intelligence is an oversimplification. Boehm (6) convincingly argues that additional processes and factors such as moralistic punishment, internalization of culturally enforced norms, symbolic language and gossiping, and social selection for altruism and self-restraint applied by groups to its members need to be considered. That notwithstanding, identifying evolutionary roots for and the dynamics of genetically controlled egalitarian social instincts is a necessary step in getting a better understanding of the origins of a uniquely human sense of right and wrong.

Und aus der Diskussion der Studie:

Animals living in a group have common interests such as defense from predators and acquisition and defense of various resources (including mating opportunities) from competitors that include conspecifics. These common interests, however, do not necessarily mean an elimination or a significant reduction of competition between group members. A variation between individuals in their fighting abilities (which is always present due to various environmental, genetic, developmental, and stochastic factors) implies that some of them can take resources from others by force. Then natural selection is expected to drive the evolution of a particular psychology with stronger individuals attempting to rob weaker individuals with the latter giving up resources without fighting back. A result is the emergence of group hierarchies in which resources are appropriated in a very nonequal way with high-rank bullies usurping a disproportionally large share (12). The more limited are the subordinates’ options outside the group, the stronger the expected degree of despotism (52). Resisting high-rank bullies alone is costly and unlikely to be successful. However, the same forces that shape the emergence of highly despotic groups dialectically create conditions for the evolution of counterdominant coalitionary behavior and psychology (11). As I have shown above, in such groups seeking personal benefits can lead to a particular other-regarding preference: All others should be more equal. A necessary condition for this preference is that the share of group reproduction obtained by a high-rank bully grows faster than his share of the group resource (increasing marginal efficiency). A way to fulfill the preference is to help the weak against the strong, even at a cost. When everybody acts to enforce equality among all other members of the group, a group-level equality develops. In the model studied here, universal, genetically controlled inequity aversion evolves as a result of each person promoting beneficial to himself (i.e., selfcentered) equality among all other individuals within the context of within-group competition. This evolution could have been the force that drove the egalitarian transition in our lineage. Once the tendencies for egalitarianism (or pair bonding) (40) are well grounded in genes, they can be elaborated and augmented by cultural norms

Also ein Modell, bei dem Zusammengearbeitet wird, um zu starke Hierarchien, die ein Ausnutzen ermöglichen, zu verhindern. Wie der Artikel darlegt klappt das insbesondere in kleinen Gruppen, auch weil man dort Hierachien besser verhindern kann. Diese Prozesse formen dann die Grundlage für ein Ausrichten auf Gleichheit, dass dann kulturell ausgeformt werden kann.