I'm just trying to internalize an interesting study coming out of the University of British Columbia, that tries to suggest that cultural forces, specifically market integration and religion allow societies to grow beyond individuals that are familiar with each other, such that people are generous to strangers. I suspect that this community size limit is above Dunbar's number, which is clearly a result of genetic heritage. The authors suggest that these forces are required for larger cohesive societies and that this goes against the conventional wisdom that our genetic heritage causes our behavioral fairness to strangers.
From the article. [J. Henrich et al., Science 327, 1480 (2010).]
These findings indicate that people living in small communities lacking market integration or world religions—absences that likely characterized all societies until the Holocene—display relatively little concern with fairness or punishing unfairness in transactions involving strangers or anonymous others. This result challenges the hypothesis that successful social interaction in large-scale societies—and the corresponding experimental findings—arise directly from an evolved psychology that mistakenly applies kin and reciprocity-based heuristics to strangers in vast populations (4, 5), without any of the "psychological workarounds" (42) that are created by norms and institutions. Moreover, it is not clear how this hypothesis can explain why we find so much variation among populations in our experimental measures and why this variation is so strongly related to MI [market integration], WR [world religion], and CS [community size]. The mere fact that the largest and most anonymous communities engage in substantially greater punishment relative to the smallest-scale societies, who punish very little, challenges this interpretation.
I also bought into the mentioned conventional wisdom and find the suggestion that kindness to strangers is cultural and not innate very surprising. Shocking even. Why can I empathize so much with strangers? Is it seriously because I exchange money and am from a society with a history of Christianity? I wonder if levels of charity can confirm any of this data. Does this research then also offer the opportunity to compare the effectiveness of different religions in their social cohesive power? Interestingly, as I understand it, the study only scored communities as having a religion if it was Islam or Christianity ie. tribal religions didn't count as religions. I am guessing therefore that pagan religions did not demonstrate a correlation to kindness to strangers. Obviously the data is pretty prone to tons of uncontrollable variables and the data itself doesn't look impressive (see above figure), but apparently the statistics are conclusive. (I'll trust the reviews at Science on this one). Also it is just a correlation, and therefore doesn't prove causality.
Great summary in the Economist.