Evolution of heritable behavioural differences in a model of social division of labour

Abstract

The spectacular diversity of personality and behaviour of animals and humans has evoked many hypotheses intended to explain its developmental and evolutionary background. Although the list of the possible contributing mechanisms seems long, we propose that an underemphasised explanation is the division of labour creating negative frequency dependent selection. We use analytical and numerical models of social division of labour to show how selection can create consistent and heritable behavioural differences in a population, where randomly sampled individuals solve a collective task together. We assume that the collective task needs collaboration of individuals performing one of the two possible subtasks. The total benefit of the group is highest when the ratio of different subtasks is closest to 1. The probability of choosing one of the two costly subtasks and the costs assigned to them are under selection. By using adaptive dynamics we show that if a trade-off between the costs of the subtasks is strong enough, then evolution leads to coexistence of specialized individuals performing one of the subtasks with high probability and low cost. Our analytical results were verified and extended by numerical simulations.

An evolutionary quantitative genetics model for phenotypic (co)variances under limited dispersal, with an application to socially synergistic traits

“…; Vásárhelyi et al. , for similar models on the evolution of specialization in well‐mixed populations). (2) Over a critical level of relatedness, selection becomes stabilizing but correlational selection remains negative, which prevents evolutionary branching and thus specialization, but still results in a negative association among traits within individuals (Fig.…”

“…4A). In this instance, evolutionary dynamics follow so-called "Black queen" dynamics (Morris et al 2012;Morris 2015, with special reference to microorganisms): individuals first evolve to produce the same amount of leaky product that is shared among individuals, but the costly maintenance of both traits leads to specialization in a single product and the evolution of crossfeeding among types (see Rueffler et al 2012;Vásárhelyi et al 2015, for similar models on the evolution of specialization in well-mixed populations).…”

Niche diversity can explain cross-cultural differences in personality structure

“…In order to help overcome these hurdles and push toward a more precise theory of personality trait distributions and structure, we develop and analyze a simple formal model to study the relationships between niche diversity, emergent personality covariation, and factor structure. Most formal models of personality traits have either concerned traits at the individual level only [49] or focused on the persistence of multiple traits (usually two) in a population due to frequency-biased selection or payoffs to division of labor [50,51,52,53,54,55]. Our model instead concerns the proposal that cross-cultural variation in personality trait structure can be largely explained by differences in the diversity of niches exerting an influence on individual traits.…”

A quantitative genetics approach to the evolution of phenotypic (co)variance under limited dispersal, with an application to socially synergistic traits

“…ducing a single public good (Figure 4a). In this instance, evolutionary dynamics follow so-called "Black queen" dynamics (Morris et al, 2012, Morris, 2015, with special reference to microorganisms): individuals first evolve to produce the same amount of leaky product that is shared among individuals, but the costly maintenance of both traits leads to specialization in a single product and the evolution of cross-feeding among types (see Rueffler et al, 2012, Vásárhelyi et al, 2015, for similar models on the evolution of specialization in well-mixed populations).…”