Signals of Belonging: Emergence of Signalling Norms as Facilitators of Trust and Parochial Cooperation

Abstract

Mechanisms of social control reinforce norms that appear harmful or wasteful, such as mutilation practices or extensive body tattoos. We suggest such norms arise to serve as signals that distinguish between ingroup “friends” and outgroup “foes”, facilitating parochial cooperation. Combining insights from research on signalling and parochial cooperation, we incorporate a trust game with signalling in an agent-based model to study the dynamics of signalling norm emergence in groups with conflicting interests. Our results show that costly signalling norms emerge from random acts of signalling in minority groups that benefit most from parochial cooperation. Majority groups are less likely to develop costly signalling norms. Yet, norms that prescribe sending costless group identity signals can easily emerge in groups of all sizes – albeit, at times, at the expense of minority group members. Further, the dynamics of signalling norm emergence differ across signal costs, relative group sizes, and levels of ingroup assortment. Our findings provide theoretical insights into norm evolution in contexts where groups develop identity markers in response to environmental challenges that put their interests at odds with the interests of other groups. Such contexts arise in zones of ethnic conflict or during contestations of existing power relations.

Partner selection and evolution of out-group avoidance

“…Interactions within networks sustain cooperation [18,19], but this mechanism also supports in-group favoritism when tags are introduced that differentiate groups [20][21][22]. Cooperation can serve as a costly signal for preferred traits [23], but group-dependent costly signaling and in-group favoritism can coevolve [24].…”

Signals of belonging: emergence of signalling norms as facilitators of trust and parochial cooperation

“…Data accessibility. The code of the agent-based simulation is available from the OSF repository: https://osf.io/nxafv/ [67].…”

Social norm change: drivers and consequences

“…This section starts with a review article on norm formation and change for AI from a complex systems perspective [24]. It proceeds with four research articles that study the emergence and/or consequences of norm change in different domains using survey research [25], agent-based simulations [26], historical data [27], and ethnographic records [28]. Baronchelli [24] in his opinion piece argues that it is crucial to regulate AI and explores three ways in which new social norms might form around the use of AI.…”

“…Macanovic et al [26] present social norms as signals that enable group members to distinguish between ingroup 'friends' and outgroup 'foes', thus facilitating parochial cooperation. They design an agent-based model based on a trust game with signalling to study the dynamics of signalling norm emergence in groups with conflicting interests.…”