Symposium on Evolution, Reputation, and Human Social Behavior

Informations pratiques
02 octobre 2023

Institut Jean Nicod, 29 rue d’Ulm, RDC B.timent Jardin (courtard, ground floor)



Eleanor A. Power, London School of Economics & Political Science
“Reputational poverty traps” and the reproduction of social inequality in South Asia
and the world

Mia Karabegović, Ecole normale supérieure
Authenticity judgments: Outputs of evolved partner choice mechanisms?

Francesca Giardini, University of Groningen
Reliable reputations and interdependence in the gossip triad

Mélusine Boon-Falleur, Ecole normale supérieure
Less wealth leads to lower perceived trustworthiness, a cross-cultural analysis

Pat Barclay, University of Guelph
Signaling your stake in others


Institut Jean Nicod, 29 rue d’Ulm, RDC Bâtiment Jardin (courtyard, ground floor)

9:00-9:15 Welcome coffee
9:15-10:45 First three presentations
10:45-11:00 Coffee break
11:00-12:00 Last two presentations

Each presentation will last for approximately 20 minutes, followed by a 10-minute Q&A session.


Eleanor A. Power: “Reputational poverty traps” and the reproduction of socialinequality in South Asia and the world

In this talk, I will introduce the idea of the “reputational poverty trap.” I will motivate this with an analytical and thenagent-based model, before introducing the plans for a cross-cultural study aimed at further exploring these dynamics.With a team including ethnographers, an experimental psychologist, and a modeller, we will examine how people’sidentities and social position influence how they are perceived by others, and so how they consequently choose toact in the world. A key element of the project will be combining social network data with experimental games playedwith known others, where we can manipulate the social exposure of participants’ actions. The project will centre onthree communities in South Asia, complemented by comparative experimental work in a number of other communities arrayed around the globe, all with the aim of exploring if, and if so how, these dynamics result in a“reputational poverty trap” that reinforces social and economic inequality. As the project is just getting underway, I ameager to get the insights of this group, so will introduce the motivation for the project and its current design.

Mia Karabegović: Authenticity judgments: Outputs of evolved part- ner choice mechanisms?

It is not surprising that people want to be — or, to be perceived as — “authentic”. Authenticity has reputationalconsequences, in addition to having a positive relation with psychological well-being; inauthenticity, on the other hand,has been likened to moral violations, causing aversion towards that which is perceived as somehow “tainted”.However, there is little agreement on what authenticity is when applied to persons, and how judgments of it are formed. Studies have shown that people tend to consider morally good actions as more reflective of a person’s trueself. Given this, we could expect there to be a bias towards considering morally good behaviors as more authenticacross the board, but people are often also skeptical of others’ motivations for doing good. How can these findings bereconciled? In this talk, I’ll give a brief summary of authenticity research so far, connecting it to partner choice mechanismsand partner competition, and argue that taking evolution into account can steer it in new, more fruitful directions.

Francesca Giardini: Reliable reputations and interdependence in the gossip triad

Many of society’s biggest policy challenges — reducing inequalities, protecting the environment, pro- viding affordable and high-quality healthcare and education, encouraging participation in the democratic process — are socialdilemmas in which individual interests are at odds with collective welfare. Reputa- tion offers an inexpensive but effective solution: by knowing each other’s standing in a social group, their past behaviors, and inclinations it ispossible to know who will likely cooperate and who will not. Rep- utation, through observability, is expected to improve accountability and then norm-following behavior. Evolutionary theories, such as indirect reciprocity and partner selection, lend support to the effectiveness of reputation-based cooperation. However, when transitioning from simplemathematical models to the complexities of human sociality, the potency of reputations is severely diminished. First,observability is seldom possible in large human groups, where reputations are based on gossip, which is not necessarily truthful or reliable. Second, reputations co-evolve with the network of relationships the agents are em- bedded in: in the process what is communicated can become completely disconnected from the observed behavior. The processesand outcomes of reputation are not well understood, with a significant gap between scholarly knowledge and real-lifeobservations. The purpose of this presentation is to delineate the inadequacies of extant theories of reputation-basedcooperation. Specifically, I will scrutinize the limitations of these theories and elucidate how they can be improvedthrough an investigation of the gossip triad. The gossip triad encompasses the sender, receiver, and target, and provides the foundation for a theory of reliable reputation.

Mélusine Boon-Falleur: Less wealth leads to lower perceived trust- worthiness, a cross-cultural analysis

People make many inferences based on cues of wealth. These inferences regarding the character and behavior ofothers have real-life consequences, for example, social distancing from individuals at the lower end of the socio-economic spectrum. In this cross-cultural study (Brazil, Colombia, Democratic Republic of Congo, India, France,Nigeria, Philippines, and the United Kingdom), we investigated the association between perceived wealth and perceived trustworthiness. In studies 1 and 2, we first investigated people’s ability to detect wealth from picturesof households in a diverse sample of participants (N = 1162). Surprisingly, people were remarkably adept atidentifying wealth, regardless of the country of origin of the pictures. In study 3, we examined stereotypes abouttrustworthiness based on implicit wealth- related cues (N =1510), covering cooperative character, behavior, and self-control. Individuals from wealthier households were consistently perceived as more trustworthy across all nations.These findings underscore the potential for discrimination against lower socioeconomic status individuals and favoringhigher socioeconomic status individuals.

Pat Barclay: Signaling your stake in others

Behavioural scientists have uncovered many evolutionary reasons for why humans cooperate with each other, butthese functions of cooperation are mostly examined in isolation. Here I use fitness interde- pendence – i.e., organisms having a stake in each other’s welfare – to start examining how these causes of cooperation caninteract with each other. First, I will present mathematical models and experimental studies showing that when peopleengage in reciprocity, they develop a stake in each other’s welfare, such that they will be willing to help even beyond the existing reciprocal relationship (e.g., anonymously). The more replaceable that partners are, the less willing thatpeople are to help. Second, I will present mathematical models and experimental studies showing that acts of helpingcan signal one’s stake in a partner, such that people will trust others who are seen to value them (and are thereforelikely to reciprocate any trust). This helping can include the provision of public goods, such as preserving the environment. Signaling one’s stake in others is an effective way of signaling one’s cooperative intent, such that fitness interdependence provides a connection between different causes of cooperation like reciprocity and signaling. As such, a better understanding of fitness interdependence can help unite our understanding of why people cooperate

This symposium is organized by Jean-Baptiste André & Julien Lie-Panis, Institut Jean Nicod.