In a recent study published in the journal Proceedings of the National Academy of Sciences, The researchers devised an evolutionary game-theoretic model and a series of agent-based tests to elucidate the evolution and persistence of gossip, arguably the most ubiquitous social human trait. Their study evaluates their hypothesis that the spread of reputation and the prevention of selfishness are the key features of the evolutionary stability of gossip, and then tests the causal pathways of this evolutionary cycle.
Their findings suggest that disseminating information about an absent third party can prompt individuals to adjust their behavior in response to others’ reputations. When combined with the tendency of individuals to behave cooperatively toward gossipers to enhance their reputation, gossip has and will continue to dominate human society for the foreseeable future.
Explaining the evolution of gossip. Image credit: Ollyy / Shutterstock
Gossip – the world’s most common mystery?
Gossip is the social dissemination of (often unconfirmed) information about an absent third party, usually conducted in an informal or unrestricted conversation. History reveals that gossip has been a fundamental feature of human civilization since ancient times, the earliest records of which can be found in Mesopotamia and ancient Greece. Science hypothesizes that gossip may be a common feature among hunter-gatherer societies, with equivalents traced to higher primate groups.
Research estimates that people today spend about an hour each day engaging in gossip. Surprisingly, studies have failed to elucidate significant group differences in the ubiquity of gossip, with all individuals, regardless of age, gender, social status, and personality types, engaging in the activity. However, just as amazing is that through thousands of years of gossip’s existence, we still don’t know where it came from, how it permeated every known human culture, and how it has remained one of the most widespread human pleasures to this day.
“Previous theories have tried to explain the origins of gossip in terms of its role in human survival, particularly in connecting large groups and maintaining cooperation. Gossip spreads information about people’s reputations and thereby enables people to choose to help other partners and avoid exploitation by selfish individuals – a mechanism widely studied as indirect reciprocity that supports cooperation. Beyond that, the possibility of being gossiped about also raises concerns about people’s reputations. As a result, people tend to behave more cooperatively under the threat of gossip.”
Although these hypotheses have their scientific merit, they focus on the benefits of gossip while failing to explain the evolution of gossip in the first place. Gossip is time- and energy-intensive and involves the exchange of knowledge, an essential resource in a resource-limited environment. Gossip should therefore be maladaptive and not occur in natural populations, with mutants quickly removed by natural selection. Moreover, these hypotheses emphasize the benefits to the gossip while downplaying the role and thoughtfulness of the benefits to the receiver – the information obtained from the gossip event must first guide and modify the recipient’s behavior before material benefits can be obtained.
The evolutionary cycle of gossip
The present study proposes the “gossip evolutionary cycle,” which hypothesizes that the interplay and positive feedback between reputation propagation and selfishness prevention allows gossip to become established as an evolutionary stable strategy (ESS). Using agent-based computer simulations, they then build a game-theoretic model incorporating two gossip functions to test this hypothesis. Once established, they use further simulations to test the pathways involved in this escalating causal relationship.
“…we argue that the reputation-diffusion function of gossip makes rumors more accessible and thereby leads more people to consider the reputations of others when interacting with them. As more people condition their behavior on the reputations of others, more people worry about their own reputations. This concern for reputation prompts them to manage their reputation by behaving more cooperatively when interacting with gossip.”
The model incorporates two decision strategies for each gossip player – “cooperate” and “gossip”. This decision tree then dictates the conditions and degree of cooperation of players under different scenarios and is based on six personality types, including unconditional collaborators (AC), unconditional defectors (AD, players who use reputation information to protect themselves (CC) and players who use reputational information to exploit others (CD) The latter two categories are sensitive to gossip and subject to the anti-ego function of the gossip feature.
The study’s reputation system represents its core innovation and dictates the process for players to develop belief systems about their counterparts. Their reputation system design allows players to infer each other’s conditional behavior and avoids additional confusion of higher-order moral judgments.
“With this setting, agents form hypotheses about each other’s underlying strategy, rather than simply rating each other as ‘good’ or ‘bad’ dichotomously or on a one-dimensional spectrum as in previous models.”
Study findings
Of the 5,000 simulations run, the vast majority (90%; N = 4,000) exhibited the evolution of gossip, all of which allowed the trait to prevail and eventually become established throughout the population, validating its robustness as an evolutionary strategy. Surprisingly, even when it was suboptimal or maladaptive, gossip still became established in populations unless its maladaptive costs were very high.
The findings of the study revealed that the exploitation (GC) strategy was the most adopted (57%) among the players. Despite this, the overall cooperation rates in the population remained high (78%). This is attributed to progressive increases in gossip density and reputation sensitivity across the population. Reputation propagation function analysis clarifies these results by revealing that gossip results in increased reputation accessibility, allowing players to make more accurate predictions about their neighbors’ strategies.
“…gossipers evolve under a wide range of parameter choices, although their proportions vary as a function of those parameters. In particular, more gossipers develop if people are in a social network where they have many stable connections, if they have deep interactions with those social connections, if they interact frequently, if they have conversations with each other frequently, if their beliefs are influenced by the gossip from moderate to severe, and if progression occurs slowly.’
conclusions
In the present study, the researchers develop a new hypothesis to explain the evolution and persistence of gossip and devise a game-theoretic model and agent-based tests to simulate the validity of the hypothesis. Their findings suggest that gossip evolves from the escalating positive feedback interaction of reputation propagation and ego aversion. Their simulations highlight the robustness of the trait and its persistence once the trait has emerged in a population.
Similar modeling frameworks applied to other aspects of human interaction may help elucidate the prevalence of behaviors that we consider routine but have profound implications for evolution and survival.
