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http://scienceweek.com/2004/sa041231-2.htm EVOLUTION OF BEHAVIOR: ON COLLECTIVE ACTION IN LARGE GROUPS Ernst Fehr The following states that one of the ways in which humans have successfully achieved large-group cooperation is by a centralized control system that rewards the cooperative efforts and punishes the non-cooperative efforts of individuals in the group. Furthermore, it also states that large-group cooperative formation was achieved in competition to another large-group cooperation (i.e. war). 1) War is a prime example of large-scale within-group cooperation between genetically unrelated individuals. War also illustrates the fact that within-group cooperation often serves the purpose of between-group aggression. Modern states are able to enforce cooperation in large groups by means of sophisticated institutions that punish individuals who refuse to meet their duties and reward those who follow their superiors' commands. The existence of such cooperation-enhancing institutions is very puzzling from an evolutionary viewpoint, however, because no other species seems to have succeeded in establishing large-scale cooperation among genetically unrelated strangers(1). Attempt to Connect this passage to Rav's Arosa message: In a non-centralized system, public opinion would be the rewarder and punisher in terms of honor (reward) and shame (punishment) in the eyes of the public. Furthermore, it could be said that a large-group cooperative formation would be arrived at out of acknowledging that (1) it is necessary, from positive examples of altruistic practice in nature; and (2) that it would be arrived at in competition to an ideal of selfishness, that would be shamed out in the eyes of society through public opinion. The following also supports the concept of public opinion's influence over society, and respect in the eyes of society as an individual's reward for altruistic actions. 2) The puzzle behind this cooperation can be summarized as follows. Institutions that enhance within-group cooperation typically benefit all group members. The effect of a single group member on the institution's success is negligible, but the contribution cost is not negligible for the individual. Why, therefore, should a self-interested individual pay the cost of sustaining cooperative institutions? More generally, why should a self-interested individual contribute anything to a public good that -- once it exists -- an individual can consume regardless of whether he contributed or not? Recent work(2) advances the scope of reputation-based models(3-5) and demonstrates that individuals' concern for their reputation may be a solution to this puzzle. The following states that, in large groups, cooperation is likely to disintegrate into selfish interests due to the self-interest of "free-riders." Thus, reciprocal altruism can only maintain high levels of cooperation in 2-person interactions. 4) In the context of the problem of public-goods provision, a reciprocally altruistic individual is willing to contribute to the public good if sufficient numbers of other group members are also willing to contribute. Unfortunately, the presence of only a small number of defectors quickly causes cooperation to unravel if it is solely based on conditionally cooperative behavior, because the defectors induce the conditional cooperators to defect as well. Theory and simulations suggest that reciprocally altruistic strategies can only sustain high levels of cooperation in two-person interactions. Moreover, experimental evidence indicates that cooperation in public-good games typically unravels because it is not possible to discipline "free riders" -- those who take advantage of others' cooperation -- if only conditionally cooperative strategies are available. The following is a shortened adaptation of an article showing examples of altruistic behavior in insects. ON ALTRUISM OF INDIVIDUALS IN INSECT SOCIETIES Adapted from: Edward O. Wilson: The Insect Societies. Harvard University Press 1971, p.321. 1) Altruism is self-destructive behavior performed for the benefit of others. The use of the word altruism in biology has been faulted by Williams and Williams (1957), who suggest that the alternative expression "social donorism" is preferable because it has less gratuitous emotional flavor. Even so, altruism has been used as a term in connection with evolutionary argumentation by Haldane (1932) and rigorous genetic theory by Hamilton (1964), and it has the great advantage of being instantly familiar. The self-destruction can range in intensity all the way from total bodily sacrifice to a slight diminishment of reproductive powers. Altruistic behavior is of course commonplace in the responses of parents toward their young. It is far less frequent, and for our purposes much more interesting, when displayed by young toward their parents or by individuals toward siblings or other, more distantly related members of the same species. Altruism is a subject of importance in evolution theory because it implies the existence of group selection, and its extreme development in the social insects is therefore of more than ordinary interest. The great scope and variety of the phenomenon in the social insects is best indicated by citing a few concrete examples: a) The soldier caste of most species of termites and ants is virtually limited in function to colony defense. Soldiers are often slow to respond to stimuli that arouse the rest of the colony, but, when they do, they normally place themselves in the position of maximum danger. When nest walls of higher termites such as Nasutitermes are broken open, for example, the white, defenseless nymphs and workers rush inward toward the concealed depths of the nest, while the soldiers press outward and mill aggressively on the outside of the nest. Nutting (personal communication) witnessed soldiers of Amitermes emersoni in Arizona emerge from the nest well in advance of the nuptial flights, wander widely around the nest vicinity, and effectively tie up in combat all foraging ants that could have endangered the emerging winged reproductives. b) I have observed that injured workers of the fire ant Solenopsis saevissima leave the nest more readily and are more aggressive on the average than their uninjured sisters. Dying workers of the harvesting ant Pogonomyrmex badius tend to leave the nest altogether. Both effects may be no more than meaningless epiphenomena, but it is also likely that the responses are altruistic. To be specific, injured workers are useless for most functions other than defense, while dying workers pose a sanitary problem. c) Alarm communication, which is employed in one form or other throughout the higher social groups, has the effect of drawing workers toward sources of danger while protecting the queens, the brood, and the unmated sexual forms. d) Honeybee workers possess barbed stings that tend to remain embedded when the insects pull away from their victims, causing part of their viscera to be torn out and the bees to be fatally injured. A similar defensive maneuver occurs in many polybiine wasps, including Synoeca surinama and at least some species of Polybia and Stelopolybia and the ant Pogonomyrmex badius. The fearsome reputation of social bees and wasps in comparison with other insects is due to their general readiness to throw their lives away upon slight provocation. e) When fed exclusively on sugar water, honeybee workers can still raise larvae -- but only by metabolizing and donating their own tissue proteins. That this donation to their sisters actually shortens their own lives is indicated by the finding of de Groot (1953) that longevity in workers is a function of protein intake. f) Female workers of most social insects curtail their own egg laying in the presence of a queen, either through submissive behavior or through biochemical inhibition. The workers of many ant and stingless bee species lay special trophic eggs that are fed principally to the larvae and queen. g) The "communal stomach", or distensible crop, together with a specially modified proventriculus, forms a complex storage and pumping system that functions in the exchange of liquid food among members of the same colony in the higher ants. In both honeybees and ants, newly fed workers often press offerings of ingluvial food on nestmates without being begged, and they may go so far as to expend their supply to a level below the colony average. 2) These diverse physiological and behavioral responses are difficult to interpret in any way except as altruistic adaptations that have evolved through the agency of natural selection operating at the colony level. The list by no means exhausts the phenomena that could be placed in the same category.