Cheating is evolutionarily assimilated with cooperation in the continuous snowdrift game

TL;DR

This paper investigates how continuous evolution in snowdrift games influences the merging of cooperative and cheating strategies, revealing that diversity often collapses into intermediate cooperation levels, impacting social fairness.

Contribution

It provides a theoretical analysis of the evolutionary dynamics in continuous snowdrift games, showing conditions under which cooperation levels merge rather than diversify.

Findings

Continuous snowdrift game tends to assimilate cooperation levels.

Gradual evolution can lead to a single intermediate cooperation strategy.

Implications for social fairness and conflict in cooperative settings.

Abstract

It is well known that in contrast to the Prisoner's Dilemma, the snowdrift game can lead to a stable coexistence of cooperators and cheaters. Recent theoretical evidence on the snowdrift game suggests that gradual evolution for individuals choosing to contribute in continuous degrees can result in the social diversification to a 100% contribution and 0% contribution through so-called evolutionary branching. Until now, however, game-theoretical studies have shed little light on the evolutionary dynamics and consequences of the loss of diversity in strategy. Here we analyze continuous snowdrift games with quadratic payoff functions in dimorphic populations. Subsequently, conditions are clarified under which gradual evolution can lead a population consisting of those with 100% contribution and those with 0% contribution to merge into one species with an intermediate contribution level. The key finding is that the continuous snowdrift game is more likely to lead to assimilation of different cooperation levels rather than maintenance of diversity. Importantly, this implies that allowing the gradual evolution of cooperative behavior can facilitate social inequity aversion in joint ventures that otherwise could cause conflicts that are based on commonly accepted notions of fairness.