Indigenous Siberian Food Sharing Networks: Social Innovation in a Transforming Economy

Evidence of direct and indirect reciprocity in network-structured economic games

“…Kin selection models 3,4 were quick to demonstrate that cooperation-defined as incurring a fitness cost to provide a fitness benefit to others 5 -can be maintained by inclusive fitness considerations broadly 6 , and kin detection and discrimination more specifically 7 . However, such mechanisms were not able to explain the wide range of cases in which humans cooperate with non-kin, as measured both by economic games [e.g., [8][9][10] ] and social network approaches [e.g., [11][12][13][14][15][16][17][18][19][20][21][22][23][24] ]. Although most networkbased studies of cooperation find that kinship is an important predictor of cooperation, there is ample evidence that other mechanisms-such as reciprocity 25 and reputation or status differentiation 26,27 -are similarly important factors in determining the structure of cooperative networks.…”

“…As with early models of kin selection, models of direct reciprocity 2,28,29 appeared well positioned to explain how cooperative networks are produced and maintained. Reciprocity with non-kin has been documented in numerous human studies [e.g., 11,12,[14][15][16][17][18][19][20][21]24 ], and in non-human animals [e.g., 30 ]-though debates over what constitutes evidence of reciprocity continue 31 .…”