Market forces influence helping behaviour in cooperatively breeding paper wasps
نویسندگان
چکیده
Biological market theory is potentially useful for understanding helping behaviour in animal societies. It predicts that competition for trading partners will affect the value of commodities exchanged. It has gained empirical support in cooperative breeders, where subordinates help dominant breeders in exchange for group membership, but so far without considering one crucial aspect: outside options. We find support for a biological market in paper wasps, Polistes dominula. We first show that females have a choice of cooperative partners. Second, by manipulating entire subpopulations in the field, we increase the supply of outside options for subordinates, freeing up suitable nesting spots and providing additional nesting partners. We predicted that by intensifying competition for help, our manipulation would force dominants to accept a lower price for group membership. As expected, subordinates reduce their foraging effort following our treatments. We conclude that to accurately predict the amount of help provided, social units cannot be viewed in isolation: the surrounding market must also be considered.
منابع مشابه
Direct fitness, reciprocity and helping: a perspective from primitively eusocial wasps.
In their review, Bergmüller et al. (2007) examine explanaions for helping based on direct fitness benefits, and suggest arallels with general cooperation theory. Bergmüller et al. 2007) focus on cooperatively breeding vertebrates. Primiively eusocial wasps, in which all individuals have the option f independent reproduction, comprise the vespid subfamilies olistinae (paper wasps) and Stenogastr...
متن کاملHelping effort in primitively eusocial wasps
In primitively eusocial and cooperatively breeding societies, there is substantial individual variation in helping effort that is not accounted for by variation in genetic relatedness. In primitively eusocial wasps, helpers have a significant chance of inheriting breeding positions. Recent models suggest that because helpers with greater expected future fitness have more to lose, they should in...
متن کاملReproductive constraints, direct fitness and indirect fitness benefits explain helping behaviour in the primitively eusocial wasp, Polistes canadensis.
A key step in the evolution of sociality is the abandonment of independent breeding in favour of helping. In cooperatively breeding vertebrates and primitively eusocial insects, helpers are capable of leaving the group and reproducing independently, and yet many do not. A fundamental question therefore is why do helpers help? Helping behaviour may be explained by constraints on independent repr...
متن کاملBiological markets in cooperative breeders: quantifying outside options
A major aim in evolutionary biology is to understand altruistic help and reproductive partitioning in cooperative societies, where subordinate helpers forego reproduction to rear dominant breeders' offspring. Traditional models of cooperation in these societies typically make a key assumption: that the only alternative to staying and helping is solitary breeding, an often unfeasible task. Using...
متن کاملConsistent cooperation in a cichlid fish is caused by maternal and developmental effects rather than heritable genetic variation.
Studies on the evolution of cooperative behaviour are typically confined to understanding its adaptive value. It is equally essential, however, to understand its potential to evolve, requiring knowledge about the phenotypic consistency and genetic basis of cooperative behaviour. While previous observational studies reported considerably high heritabilities of helping behaviour in cooperatively ...
متن کامل