The Emergence of Cultural Attractors: How Dynamic Populations of Learners Achieve Collective Cognitive Alignment

A neural network model for the evolution of reconstructive social learning

Learning from others is an important adaptation. However, the evolution of social learning and its role in the spread of socially transmitted information are not well understood. Few models of social learning account for the fact that socially transmitted information must be reconstructed by the learner, based on the learner's previous knowledge and cognition. To represent the reconstructive nature of social learning, we present a modelling framework that incorporates the evolution of a neural network and a simple yet biologically realistic learning mechanism. The framework encompasses various forms of individual and social learning and allows the investigation of their interplay. Individual-based simulations reveal that an effective neural network structure rapidly evolves, leading to adaptive inborn behaviour in static environments, pure individual learning in highly variable environments, and a combination of individual and social learning in environments of intermediate stability. However, the evolutionary outcome depends strongly on the type of social learning (social guidance versus social instruction) and the order of individual and social learning. Moreover, the evolutionary dynamics of social learning can be surprisingly complex, with replicate simulations converging to alternative outcomes. We discuss the relevance of our modelling framework for cultural evolution and suggest future avenues of research.

The cultural evolution of distortion in music (and other norms of mixed appeal)

Music traditions worldwide are subject to remarkable diversity but the origins of this variation are not well understood. Musical behaviour is the product of a multicomponent collection of abilities, some possibly evolved for music but most derived from traits serving nonmusical functions. Cultural evolution has stitched together these systems, generating variable normative practices across cultures and musical genres. Here, we describe the cultural evolution of musical distortion, a noisy manipulation of instrumental and vocal timbre that emulates nonlinear phenomena (NLP) present in the vocal signals of many animals. We suggest that listeners' sensitivity to NLP has facilitated technological developments for altering musical instruments and singing with distortion, which continues to evolve culturally via the need for groups to both coordinate internally and differentiate themselves from other groups. To support this idea, we present an agent-based model of norm evolution illustrating possible dynamics of continuous traits such as timbral distortion in music, dependent on (i) a functional optimum, (ii) intra-group cohesion and inter-group differentiation and (iii) groupishness for assortment and social learning. This account illustrates how cultural transmission dynamics can lead to diversity in musical sounds and genres, and also provides a more general explanation for the emergence of subgroup-differentiating norms.This article is part of the theme issue 'Nonlinear phenomena in vertebrate vocalizations: mechanisms and communicative functions'.

Least Effort and Alignment in Task-Oriented Communication

Conversational partners align the meanings of their words over the course of interaction to coordinate and communicate. One process of alignment is lexical entrainment, whereby partners mirror and abbreviate their word usage to converge on shared terms for referents relevant to the conversation. However, lexical entrainment may result in inefficient mimicry that does not add new information, suggesting that task-oriented communication may favor alignment through other means. The present study investigates the process of alignment in Danish conversations in which dyads learned to categorize unfamiliar "aliens" using trial-and-error feedback. Performance improved as dyad communication became less verbose, measured as a decrease in the entropy of word usage. Word usage also diverged between partners as measured by Jensen-Shannon Divergence, which indicates that alignment was not achieved through lexical entrainment. A computational model of dyadic communication is shown to account for the alien game results in terms of joint least effort. The model shows that alignment of partner referents can increase as a result of minimizing both the joint entropy of dyadic word usage and the conditional entropy of individual referents given the joint signal distribution. We conclude that the principle of least effort, originally proposed to shape language evolution, may also support alignment in task-oriented communication.

Norm reinforcement, not conformity or environmental factors, is predicted to sustain cultural variation

The maintenance of cross-cultural variation and arbitrary traditions in human populations is a key question in cultural evolution. Conformist transmission, the tendency to follow the majority, was previously considered central to this phenomenon. However, recent theory indicates that cognitive biases can greatly reduce its ability to maintain traditions. Therefore, we expanded prior models to investigate two other ways that cultural variation can be sustained: payoff-biased transmission and norm reinforcement. Our findings predict that both payoff-biased transmission and reinforcement can enhance conformist transmission's ability to maintain traditions. However, payoff-biased transmission can only sustain cultural variation if it is functionally related to environmental factors. In contrast, norm reinforcement readily generates and maintains arbitrary cultural variation. Furthermore, reinforcement results in path-dependent cultural dynamics, meaning that historical traditions influence current practices, even though group behaviours have changed. We conclude that environmental variation probably plays a role in functional cultural traditions, but arbitrary cultural variation is more plausibly due to the reinforcement of norm compliance.

How does prestige bias affect information recall during a pandemic?

The prestige theory of evolution states that our memory has an intrinsic bias to memorize information from someone of prestige. However, the evidence for information recall is mainly focused on content bias. Considering that the prestige bias can be advantageous in selecting information in contexts of uncertainty, this study assessed whether, in the scenario of the COVID-19 pandemic, the prestige bias would be favored over other models that do not possess the prestige spirit characteristics. The study was conducted through an online experiment, where participants were subjected to reading fictitious text, followed by a surprise recollection. Data were analyzed using a generalized linear mixed model, Poisson family, and logistic regression. The results showed that prestige is only prioritized in the recall due to the family model and does not present any difference from the other models tested. However, it influenced the recall of specific information, suggesting its role as a factor of cultural attraction. Furthermore, we observed that trust in science-oriented profiles can influence the recall of information during a health crisis. Finally, this study highlights the complexity of the functioning of the human mind and how several factors can act simultaneously in the recall of information.

Cultural attraction in pottery practice: Group-specific shape transformations by potters from three communities

Pottery is a quintessential indicator of human cultural dynamics. Cultural alignment of behavioral repertoires and artifacts has been considered to rest upon two distinct dynamics: selective transmission of information and culture-specific biased transformation. In a cross-cultural field experiment, we tested whether community-specific morphological features of ceramic vessels would arise when the same unfamiliar shapes were reproduced by professional potters from three different communities who threw vessels using wheels. We analyzed the details of the underlying morphogenesis development of vessels in wheel throwing. When expert potters from three different communities of practice were instructed to faithfully reproduce common unfamiliar model shapes that were not parts of the daily repertoires, the morphometric variation in the final shape was not random; rather, different potters produced vessels with more morphometric variation among than within communities, indicating the presence of community-specific deviations of morphological features of vessels. Furthermore, this was found both in the final shape and in the underlying process of morphogenesis; there was more variation in the morphogenetic path among than within communities. These results suggest that the morphological features of ceramic vessels produced by potters reliably and nonrandomly diverge among different communities. The present study provides empirical evidence that collective alignment of morphological features of ceramic vessels can arise from the community-specific habits of fashioning clay.

Cognitive Science: Piecing Together the Puzzle

Alongside significant gains in our understanding of the human mind, research in Cognitive Science has produced substantial evidence that the details of cognitive processes vary across cultures, contexts, and individuals. In order to arrive at a more nuanced account of the workings of the human mind, in this letter we argue that one challenge for the future of Cognitive Science is the integration of this evidence of variation with findings which can be generalized.