Cognitive requirements of cumulative culture: teaching is useful but not essential

The technical-reasoning network is recruited when people observe others make or teach how to make tools: An fMRI study

Cumulative technological culture is defined as the increase in efficiency and complexity of tools over generations. The role of social cognitive skills in cultural transmission has been long acknowledged. However, recent accounts emphasized the importance of non-social cognitive skills during the social transmission of technical content with a focus on technical reasoning. Here, we contribute to this double process approach by reporting an fMRI study about the neurocognitive origins of social learning. Participants watched videos depicting tool-making episodes in three social-learning conditions: reverse engineering, observation, and teaching. Our results showed that the technical-reasoning network, centered around the area PF of the left inferior parietal cortex, was preferentially activated when watching tool-making episodes. Additionally, teaching elicited the right middle temporal gyrus. This study suggests that technical reasoning underpins technological culture, while social cognition enhances learners' technical reasoning by guiding attention to key aspects of the technology.

Human culture is uniquely open-ended rather than uniquely cumulative

Theories of how humans came to be so ecologically dominant increasingly centre on the adaptive abilities of human culture and its capacity for cumulative change and high-fidelity transmission. Here we revisit this hypothesis by comparing human culture with animal cultures and cases of epigenetic inheritance and parental effects. We first conclude that cumulative change and high transmission fidelity are not unique to human culture as previously thought, and so they are unlikely to explain its adaptive qualities. We then evaluate the evidence for seven alternative explanations: the inheritance of acquired characters, the pathways of inheritance, the non-random generation of variation, the scope of heritable variation, effects on organismal fitness, effects on genetic fitness and effects on evolutionary dynamics. From these, we identify the open-ended scope of human cultural variation as a key, but generally neglected, phenomenon. We end by articulating a hypothesis for the cognitive basis of this open-endedness.

Trade-offs, control conditions, and alternative designs in the experimental study of cultural evolution

Although the theoretical foundations of the modern field of cultural evolution have been in place for over 50 y, laboratory experiments specifically designed to test cultural evolutionary theory have only existed for the last two decades. Here, we review the main experimental designs used in the field of cultural evolution, as well as major findings related to the generation of cultural variation, content- and model-based biases, cumulative cultural evolution, and nonhuman culture. We then identify methodological advances that demonstrate the iterative improvement of cultural evolution experimental methods. Finally, we focus on one common critique of cultural evolution experiments, the appropriate individual learning control condition needed to demonstrate cumulative culture, and present an original experimental investigation relevant to this critique. Participants completed a combinatorial innovation task allowing for cumulative improvement over time in one of four commonly used experimental designs/conditions: social learners in chains, social learners in groups, individual learners experiencing an extended session lasting the same accumulated time as an entire chain or group, and individual learners experiencing repeated sessions adding up to the same total time. We found that repeated individual learning resulted in superior performance to any other condition. We discuss these findings in light of the relevance of the specific criticism of previous experimental studies that purport to have demonstrated cumulative culture. We also use our findings to discuss the broad trade-offs that participants face when learning individually and socially in different contexts, including variable acquisition costs, redundancy of effort in groups, and cognitive and motivational fatigue.

Martinez L, Criado-Boado F, Müeller J, Clark A. A computational approach to selective attention in embodied approaches to cognitive archaeology

This article proposes a novel computational approach to embodied approaches in cognitive archaeology called computational cognitive archaeology (CCA). We argue that cognitive archaeology, understood as the study of the human mind based on archaeological findings such as artefacts and material remains excavated and interpreted in the present, can benefit from the integration of novel methods in computational neuroscience interested in modelling the way the brain, the body and the environment are coupled and parameterized to allow for adaptive behaviour. We discuss the kind of tasks that CCA may engage in with a narrative example of how one can model the cumulative cultural evolution of the material and cognitive components of technologies, focusing on the case of knapping technology. This article thus provides a novel theoretical framework to formalize research in cognitive archaeology using recent developments in computational neuroscience.

In search of animal normativity: a framework for studying social norms in non-human animals

Social norms - rules governing which behaviours are deemed appropriate or inappropriate within a given community - are typically taken to be uniquely human. Recently, this position has been challenged by a number of philosophers, cognitive scientists, and ethologists, who have suggested that social norms may also be found in certain non-human animal communities. Such claims have elicited considerable scepticism from norm cognition researchers, who doubt that any non-human animals possess the psychological capacities necessary for normative cognition. However, there is little agreement among these researchers about what these psychological prerequisites are. This makes empirical study of animal social norms difficult, since it is not clear what we are looking for and thus what should count as behavioural evidence for the presence (or absence) of social norms in animals. To break this impasse, we offer an approach that moves beyond contested psychological criteria for social norms. This approach is inspired by the animal culture research program, which has made a similar shift away from heavily psychological definitions of 'culture' to become organised around a cluster of more empirically tractable concepts of culture. Here, we propose an analogous set of constructs built around the core notion of a normative regularity, which we define as a socially maintained pattern of behavioural conformity within a community. We suggest methods for studying potential normative regularities in wild and captive primates. We also discuss the broader scientific and philosophical implications of this research program with respect to questions of human uniqueness, animal welfare and conservation.

Cumulative route improvements spontaneously emerge in artificial navigators even in the absence of sophisticated communication or thought

Homing pigeons (Columba livia) navigate by solar and magnetic compass, and fly home in idiosyncratic but stable routes when repeatedly released from the same location. However, when experienced pigeons fly alongside naive counterparts, their path is altered. Over several generations of turnover (pairs in which the most experienced individual is replaced with a naive one), pigeons show cumulative improvements in efficiency. Here, I show that such cumulative route improvements can occur in a much simpler system by using agent-based simulation. Artificial agents are in silico entities that navigate with a minimal cognitive architecture of goal-direction (they know roughly where the goal is), social proximity (they seek proximity to others and align headings), route memory (they recall landmarks with increasing precision), and continuity (they avoid erratic turns). Agents' behaviour qualitatively matched that of pigeons, and quantitatively fitted to pigeon data. My results indicate that naive agents benefitted from being paired with experienced agents by following their previously established route. Importantly, experienced agents also benefitted from being paired with naive agents due to regression to the goal: naive agents were more likely to err towards the goal from the perspective of experienced agents' memorised paths. This subtly biased pairs in the goal direction, resulting in intergenerational improvements of route efficiency. No cumulative improvements were evident in control studies in which agents' goal-direction, social proximity, or memory were lesioned. These 3 factors are thus necessary and sufficient for cumulative route improvements to emerge, even in the absence of sophisticated communication or thought.

Conditions under which faithful cultural transmission through teaching promotes cumulative cultural evolution

It has been argued that teaching promotes the accurate transmission of cultural traits and eventually leads to cumulative cultural evolution (CCE). However, previous studies have questioned this argument. In this study, we modified the action sequences model into a network exploring model with reinforcement learning to examine the conditions under which teaching promotes CCE. Our model incorporates a time trade-off between innovation and teaching. Simulations revealed that the positive influence of teaching on CCE depends on task difficulty. When the task was too difficult and advanced, such that it could not be accomplished through individual learning within a limited time, spending more time on teaching-even at the expense of time for innovation-contributed to CCE. On the contrary, the easier the task, the more time was spent on innovation than on teaching, which contributed to the improvement of performance. These findings suggest that teaching becomes more valuable as cultures become more complex. Therefore, humanity must have co-evolved a complex cumulative culture and teaching that supports cultural fidelity.

Greater traditionalism predicts COVID-19 precautionary behaviors across 27 societies

People vary both in their embrace of their society's traditions, and in their perception of hazards as salient and necessitating a response. Over evolutionary time, traditions have offered avenues for addressing hazards, plausibly resulting in linkages between orientations toward tradition and orientations toward danger. Emerging research documents connections between traditionalism and threat responsivity, including pathogen-avoidance motivations. Additionally, because hazard-mitigating behaviors can conflict with competing priorities, associations between traditionalism and pathogen avoidance may hinge on contextually contingent tradeoffs. The COVID-19 pandemic provides a real-world test of the posited relationship between traditionalism and hazard avoidance. Across 27 societies (N = 7844), we find that, in a majority of countries, individuals' endorsement of tradition positively correlates with their adherence to costly COVID-19-avoidance behaviors; accounting for some of the conflicts that arise between public health precautions and other objectives further strengthens this evidence that traditionalism is associated with greater attention to hazards.

Bringing cumulative technological culture beyond copying versus reasoning

The dominant view of cumulative technological culture suggests that high-fidelity transmission rests upon a high-fidelity copying ability, which allows individuals to reproduce the tool-use actions performed by others without needing to understand them (i.e., without causal reasoning). The opposition between copying versus reasoning is well accepted but with little supporting evidence. In this article, we investigate this distinction by examining the cognitive science literature on tool use. Evidence indicates that the ability to reproduce others' tool-use actions requires causal understanding, which questions the copying versus reasoning distinction and the cognitive reality of the so-called copying ability. We conclude that new insights might be gained by considering causal understanding as a key driver of cumulative technological culture.

Subjective selection and the evolution of complex culture

Why is culture the way it is? Here I argue that a major force shaping culture is subjective (cultural) selection, or the selective retention of cultural variants that people subjectively perceive as satisfying their goals. I show that people evaluate behaviors and beliefs according to how useful they are, especially for achieving goals. As they adopt and pass on those variants that seem best, they iteratively craft culture into increasingly effective-seeming forms. I argue that this process drives the development of many cumulatively complex cultural products, including effective technology, magic and ritual, aesthetic traditions, and institutions. I show that it can explain cultural dependencies, such as how certain beliefs create corresponding new practices, and I outline how it interacts with other cultural evolutionary processes. Cultural practices everywhere, from spears to shamanism, develop because people subjectively evaluate them to be effective means of satisfying regular goals.

Restricted Access to Working Memory Does Not Prevent Cumulative Score Improvement in a Cultural Evolution Task

Some theories propose that human cumulative culture is dependent on explicit, system-2, metacognitive processes. To test this, we investigated whether access to working memory is required for cumulative cultural evolution. We restricted access to adults' working-memory (WM) via a dual-task paradigm, to assess whether this reduced performance in a cultural evolution task, and a metacognitive monitoring task. In total, 247 participants completed either a grid search task or a metacognitive monitoring task in conjunction with a WM task and a matched control. Participants' behaviour in the grid search task was then used to simulate the outcome of iterating the task over multiple generations. Participants in the grid search task scored higher after observing higher-scoring examples, but could only beat the scores of low-scoring example trials. Scores did not differ significantly between the control and WM distractor blocks, although more errors were made when under WM load. The simulation showed similar levels of cumulative score improvement across conditions. However, scores plateaued without reaching the maximum. Metacognitive efficiency was low in both blocks, with no indication of dual-task interference. Overall, we found that taxing working-memory resources did not prevent cumulative score improvement on this task, but impeded it slightly relative to a control distractor task. However, we found no evidence that the dual-task manipulation impacted participants' ability to use explicit metacognition. Although we found minimal evidence in support of the explicit metacognition theory of cumulative culture, our results provide valuable insights into empirical approaches that could be used to further test predictions arising from this account.

Complex foraging behaviours in wild birds emerge from social learning and recombination of components

Recent well-documented cases of cultural evolution towards increasing efficiency in non-human animals have led some authors to propose that other animals are also capable of cumulative cultural evolution, where traits become more refined and/or complex over time. Yet few comparative examples exist of traits increasing in complexity, and experimental tests remain scarce. In a previous study, we introduced a foraging innovation into replicate subpopulations of great tits, the 'sliding-door puzzle'. Here, we track diffusion of a second 'dial puzzle', before introducing a two-step puzzle that combines both actions. We mapped social networks across two generations to ask if individuals could: (1) recombine socially-learned traits and (2) socially transmit a two-step trait. Our results show birds could recombine skills into more complex foraging behaviours, and naïve birds across both generations could learn the two-step trait. However, closer interrogation revealed that acquisition was not achieved entirely through social learning-rather, birds socially learned components before reconstructing full solutions asocially. As a consequence, singular cultural traditions failed to emerge, although subpopulations of birds shared preferences for a subset of behavioural variants. Our results show that while tits can socially learn complex foraging behaviours, these may need to be scaffolded by rewarding each component. This article is part of a discussion meeting issue 'The emergence of collective knowledge and cumulative culture in animals, humans and machines'.

Human cumulative culture and the exploitation of natural phenomena

Cumulative cultural evolution (CCE)-defined as the process by which beneficial modifications are culturally transmitted and progressively accumulated over time-has long been argued to underlie the unparalleled diversity and complexity of human culture. In this paper, I argue that not just any kind of cultural accumulation will give rise to human-like culture. Rather, I suggest that human CCE depends on the gradual exploitation of natural phenomena, which are features of our environment that, through the laws of physics, chemistry or biology, generate reliable effects which can be exploited for a purpose. I argue that CCE comprises two distinct processes: optimizing cultural traits that exploit a given set of natural phenomena (Type I CCE) and expanding the set of natural phenomena we exploit (Type II CCE). I argue that the most critical features of human CCE, including its open-ended dynamic, stems from Type II CCE. Throughout the paper, I contrast the two processes and discuss their respective socio-cognitive requirements. This article is part of a discussion meeting issue 'The emergence of collective knowledge and cumulative culture in animals, humans and machines'.

Negative observational learning might play a limited role in the cultural evolution of technology

Theoretical and empirical studies of the cultural evolution in technology have often focused on positive observational learning, i.e., copying a successful individual. However, negative observational learning, i.e., avoiding negative or bad exemplar behavior, is ubiquitous in humans and other animals. In this paper, we experimentally investigate whether observing negative examples can assist in tool making in the virtual arrowhead task, which has been widely applied to test the theory of cultural evolution in the technological domain. We set three conditions that differ in the kinds of social learning available to participants: (1) positive observational learning, (2) negative observational learning, and (3) pure asocial learning. The results of the positive observational and pure asocial learning conditions replicated previous studies; i.e., participants in the positive observational learning condition outperformed those in the asocial learning condition. In contrast, opportunities to observe negative examples did not increase the performance compared to pure asocial learning. Computer simulations in the same setting showed that the presence of negative exemplars is in theory beneficial to participants, providing additional pieces of information on the relationship between arrowhead designs and their performance scores. These findings together suggest that negative observational learning might play only a limited role in the cultural evolution of technologies possibly due to a cognitive bias in humans toward copying.

On the psychological origins of tool use

The ubiquity of tool use in human life has generated multiple lines of scientific and philosophical investigation to understand the development and expression of humans' engagement with tools and its relation to other dimensions of human experience. However, existing literature on tool use faces several epistemological challenges in which the same set of questions generate many different answers. At least four critical questions can be identified, which are intimately intertwined-(1) What constitutes tool use? (2) What psychological processes underlie tool use in humans and nonhuman animals? (3) Which of these psychological processes are exclusive to tool use? (4) Which psychological processes involved in tool use are exclusive to Homo sapiens? To help advance a multidisciplinary scientific understanding of tool use, six author groups representing different academic disciplines (e.g., anthropology, psychology, neuroscience) and different theoretical perspectives respond to each of these questions, and then point to the direction of future work on tool use. We find that while there are marked differences among the responses of the respective author groups to each question, there is a surprising degree of agreement about many essential concepts and questions. We believe that this interdisciplinary and intertheoretical discussion will foster a more comprehensive understanding of tool use than any one of these perspectives (or any one of these author groups) would (or could) on their own.

Implications of instrumental and ritual stances for traditionalism–threat responsivity relationships

Jagiello et al.'s bifocal stance theory provides a useful theoretical framework for attempting to understand the connection between greater adherence to traditional norms and greater sensitivity to threats in the world. Here, we examine the implications of the instrumental and ritual stances with regard to various evolutionary explanations for traditionalism–threat sensitivity linkages.

On the Neurocognitive Co-Evolution of Tool Behavior and Language: Insights from the Massive Redeployment Framework

Understanding the link between brain evolution and the evolution of distinctive features of modern human cognition is a fundamental challenge. A still unresolved question concerns the co-evolution of tool behavior (i.e., tool use or tool making) and language. The shared neurocognitive processes hypothesis suggests that the emergence of the combinatorial component of language skills within the frontal lobe/Broca's area made possible the complexification of tool-making skills. The importance of the frontal lobe/Broca's area in tool behavior is somewhat surprising with regard to the literature on neuropsychology and cognitive neuroscience, which has instead stressed the critical role of the left inferior parietal lobe. Therefore, to be complete, any version of the shared neurocognitive processes hypothesis needs to integrate the potential interactions between the frontal lobe/Broca's area and the left inferior parietal lobe as well as their co-evolution at a phylogenetic level. Here, we sought to provide the first elements of answer through the use of the massive deployment framework, which posits that evolutionarily older brain areas are deployed in more cognitive functions (i.e., they are less specific). We focused on the left parietal cortex, and particularly the left areas PF, PGI, and anterior intraparietal (AIP), which are known to be involved in tool use, language, and motor control, respectively. The deployment of each brain area in different cognitive functions was measured by conducting a meta-analysis of neuroimaging studies. Our results confirmed the pattern of specificity for each brain area and also showed that the left area PGI was far less specific than the left areas PF and AIP. From these findings, we discuss the different evolutionary scenarios depicting the potential co-evolution of the combinatorial and generative components of language and tool behavior in our lineage.

Prestige and content biases together shape the cultural transmission of narratives

Cultural transmission biases such as prestige are thought to have been a primary driver in shaping the dynamics of human cultural evolution. However, few empirical studies have measured the importance of prestige relative to other effects, such as content biases present within the information being transmitted. Here, we report the findings of an experimental transmission study designed to compare the simultaneous effects of a model using a high- or low-prestige regional accent with the presence of narrative content containing social, survival, emotional, moral, rational, or counterintuitive information in the form of a creation story. Results from multimodel inference reveal that prestige is a significant factor in determining the salience and recall of information, but that several content biases, specifically social, survival, negative emotional, and biological counterintuitive information, are significantly more influential. Further, we find evidence that reliance on prestige cues may serve as a conditional learning strategy when no content cues are available. Our results demonstrate that content biases serve a vital and underappreciated role in cultural transmission and cultural evolution. Social media summary: Storyteller and tale are both key to memorability, but some content is more important than the storyteller's prestige.

Of pathogens and party lines: Social conservatism positively associates with COVID-19 precautions among U.S. Democrats but not Republicans

Social liberals tend to be less pathogen-avoidant than social conservatives, a pattern consistent with a model wherein ideological differences stem from differences in threat reactivity. Here we investigate if and how individual responses to a shared threat reflect those patterns of ideological difference. In seeming contradiction to the general association between social conservatism and pathogen avoidance, the more socially conservative political party in the United States has more consistently downplayed the dangers of COVID-19 during the ongoing pandemic. This puzzle offers an opportunity to examine the contributions of multiple factors to disease avoidance. We investigated the relationship between social conservatism and COVID-19 precautionary behavior in light of the partisan landscape of the United States. We explored whether consumption of, and attitudes toward, different sources of information, as well as differential evaluation of various threats caused by the pandemic-such as direct health costs versus indirect harms to the economy and individual liberties-shape partisan differences in responses to the pandemic in ways that overwhelm the contributions of social conservatism. In two pre-registered studies, socially conservative attitudes correlate with self-reported COVID-19 prophylactic behaviors, but only among Democrats. Reflecting larger societal divisions, among Republicans and Independents, the absence of a positive relationship between social conservatism and COVID-19 precautions appears driven by lower trust in scientists, lower trust in liberal and moderate sources, lesser consumption of liberal news media, and greater economic conservatism.

Co-occurrence of Ostensive Communication and Generalizable Knowledge in Forager Storytelling : Cross-Cultural Evidence of Teaching in Forager Societies

Teaching is hypothesized to be a species-typical behavior in humans that contributed to the emergence of cumulative culture. Several within-culture studies indicate that foragers depend heavily on social learning to acquire practical skills and knowledge, but it is unknown whether teaching is universal across forager populations. Teaching can be defined ethologically as the modification of behavior by an expert in the presence of a novice, such that the expert incurs a cost and the novice acquires skills/knowledge more efficiently or that it would not acquire otherwise. One behavioral modification hypothesized to be an adaptation for teaching is ostensive communication-exaggerations of prosody and gesture that signal intent to transmit generalizable knowledge and indicate the intended receiver. On this view, the use of ostensive communication in conjunction with the transmission of generalizable knowledge constitutes evidence of teaching. Oral storytelling appears to meet these criteria: Indigenous peoples regard their traditions as important sources of ecological and social knowledge, and oral storytelling is widely reported to employ paralinguistic communication. To test this hypothesis, descriptions of performed narrative in forager societies were coded for the use of 14 ostensive-communicative behaviors and the presence of generalizable knowledge. Although biased toward North America, the study sample comprised 53 forager cultures spanning five continents, 34 language families, and diverse biomes. All cultures evinced the predicted behaviors. Results suggest that foragers use storytelling as a mode of instruction, thus providing cross-cultural evidence of teaching in forager populations.

Human biases limit cumulative innovation

Is technological advancement constrained by biases in human cognition? People in all societies build on discoveries inherited from previous generations, leading to cumulative innovation. However, biases in human learning and memory may influence the process of knowledge transmission, potentially limiting this process. Here, we show that cumulative innovation in a continuous optimization problem is systematically constrained by human biases. In a large (n = 1250) behavioural study using a transmission chain design, participants searched for virtual technologies in one of four environments after inheriting a solution from previous generations. Participants converged on worse solutions in environments misaligned with their biases. These results substantiate a mathematical model of cumulative innovation in Bayesian agents, highlighting formal relationships between cultural evolution and distributed stochastic optimization. Our findings provide experimental evidence that human biases can limit the advancement of knowledge in a controlled laboratory setting, reinforcing concerns about bias in creative, scientific and educational contexts.

Cognitive prerequisites for cumulative culture are context-dependent: Children's potential for ratcheting depends on cue longevity

Human cumulative culture has been suggested to depend on human-unique cognitive mechanisms, explaining its apparent absence in other species. We show that the potential for exhibiting cumulative culture depends on the cognitive abilities of the agents and the demands associated with using information generated by others' activity. 154 children aged 3-6 years played a searching game ("Find the Treasure"), taking their turn after a puppet demonstrator. The puppet's attempt revealed information about the contents of the locations searched, which could be exploited to target rewarded locations, and avoid unrewarded ones. Two conditions were presented, intended to capture realistic variation in the transience of the cues generated by another individual's activity. In one condition, the puppet's demonstration provided transient information - boxes were opened, seen to be rewarded or not, and then closed. In the other condition the puppet's chosen boxes remained partially open, providing an enduring visible cue as to whether that location was rewarded. Children undertook three trials of varying demonstration success, and we used patterns of performance to infer the potential for improvement over multiple generations of transmission. In the Enduring Cues condition, children's performance demonstrated the potential for cumulative culture. In contrast, in the Transient Information condition, only older children showed improved performances following higher success demonstrations and overall performance was not compatible with the possibility of improvements over generations of social transmission. We conclude that under certain conditions cumulative culture could occur in many species, but in a broader range of contexts in humans.

Of pathogens and party lines: Social conservatism positively associates with COVID-19 precautions among U.S. Democrats but not Republicans

Social liberals tend to be less pathogen-avoidant than social conservatives, a pattern consistent with a model wherein ideological differences stem from differences in threat reactivity. Here we investigate if and how individual responses to a shared threat reflect those patterns of ideological difference. In seeming contradiction to the general association between social conservatism and pathogen avoidance, the more socially conservative political party in the United States has more consistently downplayed the dangers of COVID-19 during the ongoing pandemic. This puzzle offers an opportunity to examine the contributions of multiple factors to disease avoidance. We investigated the relationship between social conservatism and COVID-19 precautionary behavior in light of the partisan landscape of the United States. We explored whether consumption of, and attitudes toward, different sources of information, as well as differential evaluation of various threats caused by the pandemic-such as direct health costs versus indirect harms to the economy and individual liberties-shape partisan differences in responses to the pandemic in ways that overwhelm the contributions of social conservatism. In two pre-registered studies, socially conservative attitudes correlate with self-reported COVID-19 prophylactic behaviors, but only among Democrats. Reflecting larger societal divisions, among Republicans and Independents, the absence of a positive relationship between social conservatism and COVID-19 precautions appears driven by lower trust in scientists, lower trust in liberal and moderate sources, lesser consumption of liberal news media, and greater economic conservatism.

The Pedagogue, the Engineer, and the Friend : From Whom Do We Learn?

Humans can follow different social learning strategies, sometimes oriented toward the models' characteristics (i.e., who-strategies). The goal of the present study was to explore which who-strategy is preferentially followed in the technological context based on the models' psychological characteristics. We identified three potential who-strategies: Copy the pedagogue (a model with high theory-of-mind skills), copy the engineer (a model with high technical-reasoning skills), and copy the friend (a model with high level of prosocialness). We developed a closed-group micro-society paradigm in which participants had to build the highest possible towers. Participants began with an individual building phase. Then, they were gathered to discuss the best solutions to increase tower height. After this discussion phase, they had to make a new building attempt, followed by another discussion phase, and so forth for a total of six building phases and five discussion rounds. This methodology allowed us to create an attraction score for each participant (the more an individual was copied in a group, the greater the attraction score). We also assessed participants' theory-of-mind skills, technical-reasoning skills, and prosocialness to predict participants' attraction scores based on these measures. Results show that we learn from engineers (high technical-reasoning skills) because they are the most successful. Their attraction power is not immediate, but after they have been identified as attractors, their technique is copied irrespective of their pedagogy (theory-of-mind skills) or friendliness (prosocialness). These findings open avenues for the study of the cognitive bases of human technological culture.

The value of teaching increases with tool complexity in cumulative cultural evolution

Human cumulative cultural evolution (CCE) is recognized as a powerful ecological and evolutionary force, but its origins are poorly understood. The long-standing view that CCE requires specialized social learning processes such as teaching has recently come under question, and cannot explain why such processes evolved in the first place. An alternative, but largely untested, hypothesis is that these processes gradually coevolved with an increasing reliance on complex tools. To address this, we used large-scale transmission chain experiments (624 participants), to examine the role of different learning processes in generating cumulative improvements in two tool types of differing complexity. Both tool types increased in efficacy across experimental generations, but teaching only provided an advantage for the more complex tools. Moreover, while the simple tools tended to converge on a common design, the more complex tools maintained a diversity of designs. These findings indicate that the emergence of cumulative culture is not strictly dependent on, but may generate selection for, teaching. As reliance on increasingly complex tools grew, so too would selection for teaching, facilitating the increasingly open-ended evolution of cultural artefacts.

The value of teaching increases with tool complexity in cumulative cultural evolution

Human cumulative cultural evolution (CCE) is recognized as a powerful ecological and evolutionary force, but its origins are poorly understood. The long-standing view that CCE requires specialized social learning processes such as teaching has recently come under question, and cannot explain why such processes evolved in the first place. An alternative, but largely untested, hypothesis is that these processes gradually coevolved with an increasing reliance on complex tools. To address this, we used large-scale transmission chain experiments (624 participants), to examine the role of different learning processes in generating cumulative improvements in two tool types of differing complexity. Both tool types increased in efficacy across experimental generations, but teaching only provided an advantage for the more complex tools. Moreover, while the simple tools tended to converge on a common design, the more complex tools maintained a diversity of designs. These findings indicate that the emergence of cumulative culture is not strictly dependent on, but may generate selection for, teaching. As reliance on increasingly complex tools grew, so too would selection for teaching, facilitating the increasingly open-ended evolution of cultural artefacts.

Inferring Behavior From Partial Social Information Plays Little or No Role in the Cultural Transmission of Adaptive Traits

Many human cultural traits become increasingly beneficial as they are repeatedly transmitted, thanks to an accumulation of modifications made by successive generations. But how do later generations typically avoid modifications which revert traits to less beneficial forms already sampled and rejected by earlier generations? And how can later generations do so without direct exposure to their predecessors' behavior? One possibility is that learners are sensitive to cues of non-random production in others' behavior, and that particular variants (e.g., those containing structural regularities unlikely to occur spontaneously) have been produced deliberately and with some effort. If this non-random behavior is attributed to an informed strategy, then the learner may infer that apparent avoidance of certain possibilities indicates that these have already been sampled and rejected. This could potentially prevent performance plateaus resulting from learners modifying inherited behaviors randomly. We test this hypothesis in four experiments in which participants, either individually or in interacting dyads, attempt to locate rewards in a search grid, guided by partial information about another individual's experience of the task. We find that in some contexts, valid inferences about another's behavior can be made from partial information, and these inferences can be used in a way which facilitates trait adaptation. However, the benefit of these inferences appears to be limited, and in many contexts-including some which have the potential to make inferring the experience of another individual easier-there appears to be no benefit at all. We suggest that inferring previous behavior from partial social information plays a minimal role in the adaptation of cultural traits.

Supporting the weight of the elephant in the room: Technical intelligence propped up by social cognition and language

We consider the evolutionary plausibility of Osiurak and Reynaud's (O&R) arguments. We argue that technical reasoning is not quite the magic bullet that O&R assume, and instead propose a co-evolutionary account of the interplay between technical reasoning and social learning, with language emerging as a vital issue neglected in O&R's account.

The evolution of high-fidelity social learning

A defining feature of human culture is that knowledge and technology continually improve over time. Such cumulative cultural evolution (CCE) probably depends far more heavily on how reliably information is preserved than on how efficiently it is refined. Therefore, one possible reason that CCE appears diminished or absent in other species is that it requires accurate but specialized forms of social learning at which humans are uniquely adept. Here, we develop a Bayesian model to contrast the evolution of high-fidelity social learning, which supports CCE, against low-fidelity social learning, which does not. We find that high-fidelity transmission evolves when (1) social and (2) individual learning are inexpensive, (3) traits are complex, (4) individual learning is abundant, (5) adaptive problems are difficult and (6) behaviour is flexible. Low-fidelity transmission differs in many respects. It not only evolves when (2) individual learning is costly and (4) infrequent but also proves more robust when (3) traits are simple and (5) adaptive problems are easy. If conditions favouring the evolution of high-fidelity transmission are stricter (3 and 5) or harder to meet (2 and 4), this could explain why social learning is common, but CCE is rare.

Technition: When Tools Come Out of the Closet

People are ambivalently enthusiastic and anxious about how far technology can go. Therefore, understanding the neurocognitive bases of the human technical mind should be a major topic of the cognitive sciences. Surprisingly, however, scientists are not interested in this topic or address it only marginally in other mainstream domains (e.g., motor control, action observation, social cognition). In fact, this lack of interest may hinder our understanding of the necessary neurocognitive skills underlying our appetence for transforming our physical environment. Here, we develop the thesis that our technical mind originates in perhaps uniquely human neurocognitive skills, namely, technical-reasoning skills involving the area PF within the left inferior parietal lobe. This thesis creates an epistemological rupture with the state of the art that justifies the emergence of a new field in the cognitive sciences (i.e., technition) dedicated to the intelligence hidden behind tools and other forms of technologies, including constructions.

Corvid Technologies: How Do New Caledonian Crows Get Their Tool Designs?

Recent research shows that New Caledonian crows can incorporate information from researcher-made objects into objects they subsequently manufacture. This 'mental template matching' is one of several possible - mutually compatible - mechanisms for the cultural transmission of tool designs among wild crows.

Roles of Technical Reasoning, Theory of Mind, Creativity, and Fluid Cognition in Cumulative Technological Culture

Cumulative technological culture can be defined as the progressive diversification, complexification, and enhancement of technological traits through generations. An outstanding issue is to specify the cognitive bases of this phenomenon. Based on the literature, we identified four potential cognitive factors: namely, theory-of-mind, technical-reasoning, creativity, and fluid-cognitive skills. The goal of the present study was to test which of these factors-or a combination thereof-best predicted the cumulative performance in two experimental, micro-society conditions (Communication and Observation conditions; n = 100 each) differing in the nature of the interaction (verbal, visual) allowed between participants. The task was to build the highest possible tower. Participants were also assessed on the four aforementioned cognitive factors in order to predict cumulative performance (tower height) and attractiveness. Our findings indicate that technical-reasoning skills are the best predictor of cumulative performance (tower height), even if their role may be restricted to the specific technological domain. Theory-of-mind skills may have a facilitator role, particularly in the Communication condition. Creativity can also help in the generation of novel ideas, but it is not sufficient to support innovation. Finally, fluid cognition is not involved in cumulative technological culture. Taken together, these findings suggest that domain-specific knowledge (i.e., technical-reasoning skills) remains critical for explaining cumulative technological culture.

The elephant in the room: What matters cognitively in cumulative technological culture

Cumulative technological culture (CTC) refers to the increase in the efficiency and complexity of tools and techniques in human populations over generations. A fascinating question is to understand the cognitive origins of this phenomenon. Because CTC is definitely a social phenomenon, most accounts have suggested a series of cognitive mechanisms oriented toward the social dimension (e.g., teaching, imitation, theory of mind, and metacognition), thereby minimizing the technical dimension and the potential influence of non-social, cognitive skills. What if we have failed to see the elephant in the room? What if social cognitive mechanisms were only catalyzing factors and not the sufficient and necessary conditions for the emergence of CTC? In this article, we offer an alternative, unified cognitive approach to this phenomenon by assuming that CTC originates in non-social cognitive skills, namely technical-reasoning skills which enable humans to develop the technical potential necessary to constantly acquire and improve technical information. This leads us to discuss how theory of mind and metacognition, in concert with technical reasoning, can help boost CTC. The cognitive approach developed here opens up promising new avenues for reinterpreting classical issues (e.g., innovation, emulation vs. imitation, social vs. asocial learning, cooperation, teaching, and overimitation) in a field that has so far been largely dominated by other disciplines, such as evolutionary biology, mathematics, anthropology, archeology, economics, and philosophy.

Cultural transmission in a food preparation task: The role of interactivity, innovation and storytelling

Interactive conversation drives the transmission of cultural information in small groups and large networks. In formal (e.g. schools) and informal (e.g. home) learning settings, interactivity does not only allow individuals and groups to faithfully transmit and learn new knowledge and skills, but also to boost cumulative cultural evolution. Here we investigate how interactivity affects performance, teaching, learning, innovation and chosen diffusion mode (e.g. instructional discourse vs. storytelling) of previously acquired information in a transmission chain experiment. In our experiment, participants (n = 288) working in 48 chains with three generations of pairs had to learn and complete a collaborative food preparation task (ravioli-making), and then transmit their experience to a new generation of participants in an interactive and non-interactive condition. Food preparation is a real-world task that it is taught and learned across cultures and transmitted over generations in families and groups. Pairs were defined as teachers or learners depending on their role in the transmission chain. The number of good exemplars of ravioli each pair produced was taken as measurement of performance. Contrary to our expectations, the results did not reveal that (1) performance increased over generations or that (2) interactivity in transmission sessions promoted increased performance. However, the results showed that (3) interactivity promoted the transmission of more information from teachers to learners; (4) increased quantity of information transmission from teachers led to higher performance in learners; (5) higher performance generations introduced more innovations in transmission sessions; (6) learners applied those transmitted innovations to their performance which made them persist over generations; (7) storytelling was specialized for the transmission of non-routine, unexpected information. Our findings offer new insights on how interactivity, innovation and storytelling affect the cultural transmission of complex collaborative tasks.

Experimental assessment of capacities for cumulative culture: Review and evaluation of methods

In the current literature, there are few experimental tests of capacities for cumulative cultural evolution in nonhuman species. There are even fewer examples of such tests in young children. This limited evidence is noteworthy given widespread interest in the apparent distinctiveness of human cumulative culture, and the potentially significant theoretical implications of identifying related capacities in nonhumans or very young children. We evaluate experimental methods upon which claims of capacities for cumulative culture, or lack thereof, have been based. Although some of the established methods (those simulating generational succession) have the potential to identify positive evidence that fulfills widely accepted definitions of cumulative culture, the implementation of these methods entails significant logistical challenges. This is particularly true for testing populations that are difficult to access in large numbers, or those not amenable to experimental control. This presents problems for generating evidence that would be sufficient to support claims of capacities for cumulative culture, and these problems are magnified for establishing convincing negative evidence. We discuss alternative approaches to assessing capacities for cumulative culture, which circumvent logistical problems associated with experimental designs involving chains of learners. By inferring the outcome of repeated transmission from the input–output response patterns of individual subjects, sample size requirements can be massively reduced. Such methods could facilitate comparisons between populations, for example, different species, or children of a range of ages. We also detail limitations and challenges of this alternative approach, and discuss potential avenues for future research.

This article is categorized under:

Cognitive Biology > Evolutionary Roots of Cognition

Cognitive Biology > Cognitive Development

Psychology > Comparative Psychology

High-fidelity copying is not necessarily the key to cumulative cultural evolution: a study in monkeys and children

The unique cumulative nature of human culture has often been explained by high-fidelity copying mechanisms found only in human social learning. However, transmission chain experiments in human and non-human primates suggest that cumulative cultural evolution (CCE) might not necessarily depend on high-fidelity copying after all. In this study, we test whether defining properties of CCE can emerge in a non-copying task. We performed transmission chain experiments in Guinea baboons and human children where individuals observed and produced visual patterns composed of four squares on touchscreen devices. In order to be rewarded, participants had to avoid touching squares that were touched by a previous participant. In other words, they were rewarded for innovation rather than copying. Results nevertheless exhibited fundamental properties of CCE: an increase over generations in task performance and the emergence of systematic structure. However, these properties arose from different mechanisms across species: children, unlike baboons, converged in behaviour over generations by copying specific patterns in a different location, thus introducing alternative copying mechanisms into the non-copying task. In children, prior biases towards specific shapes led to convergence in behaviour across chains, while baboon chains showed signs of lineage specificity. We conclude that CCE can result from mechanisms with varying degrees of fidelity in transmission and thus that high-fidelity copying is not necessarily the key to CCE.

Prestige and dominance-based hierarchies exist in naturally occurring human groups, but are unrelated to task-specific knowledge

Prestige and dominance are thought to be two evolutionarily distinct routes to gaining status and influence in human social hierarchies. Prestige is attained by having specialist knowledge or skills that others wish to learn, whereas dominant individuals use threat or fear to gain influence over others. Previous studies with groups of unacquainted students have found prestige and dominance to be two independent avenues of gaining influence within groups. We tested whether this result extends to naturally occurring social groups. We ran an experiment with 30 groups of people from Cornwall, UK (n = 150). Participants answered general knowledge questions individually and as a group, and subsequently nominated a representative to answer bonus questions on behalf of the team. Participants then anonymously rated all other team-mates on scales of prestige, dominance, likeability and influence on the task. Using a model comparison approach with Bayesian multi-level models, we found that prestige and dominance ratings were predicted by influence ratings on the task, replicating previous studies. However, prestige and dominance ratings did not predict who was nominated as team representative. Instead, participants nominated team members with the highest individual quiz scores, despite this information being unavailable to them. Interestingly, team members who were initially rated as being high status in the group, such as a team captain or group administrator, had higher ratings of both dominance and prestige than other group members. In contrast, those who were initially rated as someone from whom others would like to learn had higher prestige, but not higher dominance, supporting the claim that prestige reflects social learning opportunities. Our results suggest that prestige and dominance hierarchies do exist in naturally occurring social groups, but that these hierarchies may be more domain-specific and less flexible than we anticipated.

What is cumulative cultural evolution?

In recent years, the phenomenon of cumulative cultural evolution (CCE) has become the focus of major research interest in biology, psychology and anthropology. Some researchers argue that CCE is unique to humans and underlies our extraordinary evolutionary success as a species. Others claim to have found CCE in non-human species. Yet others remain sceptical that CCE is even important for explaining human behavioural diversity and complexity. These debates are hampered by multiple and often ambiguous definitions of CCE. Here, we review how researchers define, use and test CCE. We identify a core set of criteria for CCE which are both necessary and sufficient, and may be found in non-human species. We also identify a set of extended criteria that are observed in human CCE but not, to date, in other species. Different socio-cognitive mechanisms may underlie these different criteria. We reinterpret previous theoretical models and observational and experimental studies of both human and non-human species in light of these more fine-grained criteria. Finally, we discuss key issues surrounding information, fitness and cognition. We recommend that researchers are more explicit about what components of CCE they are testing and claiming to demonstrate.

Causal understanding is not necessary for the improvement of culturally evolving technology

Bows and arrows, houses and kayaks are just a few examples of the highly optimized tools that humans have produced and used to colonize new environments^1,2. Because there is much evidence that humans' cognitive abilities are unparalleled^3,4, many believe that such technologies resulted from our superior causal reasoning abilities^5-7. However, others have stressed that the high dimensionality of human technologies makes them very difficult to understand causally⁸. Instead, they argue that optimized technologies emerge through the retention of small improvements across generations without requiring understanding of how these technologies work^1,9. Here we show that a physical artefact becomes progressively optimized across generations of social learners in the absence of explicit causal understanding. Moreover, we find that the transmission of causal models across generations has no noticeable effect on the pace of cultural evolution. The reason is that participants do not spontaneously create multidimensional causal theories but, instead, mainly produce simplistic models related to a salient dimension. Finally, we show that the transmission of these inaccurate theories constrains learners' exploration and has downstream effects on their understanding. These results indicate that complex technologies need not result from enhanced causal reasoning but, instead, can emerge from the accumulation of improvements made across generations.

Electoral fortunes reverse, mindsets do not

Conservatives and liberals have previously been shown to differ in the propensity to view socially-transmitted information about hazards as more plausible than that concerning benefits. Given differences between conservatives and liberals in threat sensitivity and dangerous-world beliefs, correlations between political orientation and negatively-biased credulity may thus reflect endogenous mindsets. Alternatively, such results may owe to the political hierarchy at the time of previous research, as the tendency to see dark forces at work is thought to be greater among those who are out of political power. Adjudicating between these accounts can inform how societies respond to the challenge of alarmist disinformation campaigns. We exploit the consequences of the 2016 U.S. elections to test these competing explanations of differences in negatively-biased credulity and conspiracism as a function of political orientation. Two studies of Americans reveal continued positive associations between conservatism, negatively-biased credulity, and conspiracism despite changes to the power structure in conservatives’ favor.

Using Experimental Research Designs to Explore the Scope of Cumulative Culture in Humans and Other Animals

In humans, cultural evolutionary processes are capable of shaping our cognition, because the conceptual tools we learn from others enable mental feats which otherwise would be beyond our capabilities. This is possible because human culture supports the intergenerational accumulation of skills and knowledge, such that later generations can benefit from the experience and exploration efforts of their predecessors. However, it remains unclear how exactly human social transmission supports the accumulation of advantageous traits, and why we see little evidence of this in the natural behavior of other species. Thus, it is difficult to know whether the cognitive abilities of other animals might be similarly scaffolded by processes of cultural evolution. In this article, I discuss how experimental studies of cultural evolution have contributed to our understanding of human cumulative culture, as well as some of the limitations of these approaches. I also discuss how similar research designs can be used to evaluate the potential for cumulative culture in other species. Such research may be able to clarify what distinguishes human cumulative culture from related phenomena in nonhumans, shedding light on the issue of whether other species also have the potential to develop cognitive capacities that are outcomes of cultural evolution.

Culture drives cognitive evolution by supporting the transmission and intergenerational accumulation of skills and knowledge, based on social learning and teaching: Later generations benefit from what their predecessors acquired. Taking a metaperspective on those experimental studies that explore the mechanisms underlying cultural transmission, Caldwell discusses their potential for generating valuable insights, their possible limitations, and their generalizability to other species.

Wild chimpanzees select tool material based on efficiency and knowledge

Some animals have basic culture, but to date there is not much evidence that cultural traits evolve as part of a cumulative process as seen in humans. This may be due to limits in animal physical cognition, such as an inability to compare the efficiency of a novel behavioural innovation with an already existing tradition. We investigated this possibility with a study on a natural tool innovation in wild chimpanzees: moss-sponging, which recently emerged in some individuals to extract mineral-rich liquids at a natural clay-pit. The behaviour probably arose as a variant of leaf-sponging, a tool technique seen in all studied chimpanzee communities. We found that moss-sponges not only absorbed more liquid but were manufactured and used more rapidly than leaf-sponges, suggesting a functional improvement. To investigate whether chimpanzees understood the advantage of moss- over leaf-sponges, we experimentally offered small amounts of rainwater in an artificial cavity of a portable log, together with both sponge materials, moss and leaves. We found that established moss-spongers (having used both leaves and moss to make sponges) preferred moss to prepare a sponge to access the rainwater, whereas leaf-spongers (never observed using moss) preferred leaves. Survey data finally demonstrated that moss was common in forest areas near clay-pits but nearly absent in other forest areas, suggesting that natural moss-sponging was at least partly constrained by ecology. Together, these results suggest that chimpanzees perceive functional improvements in tool quality, a crucial prerequisite for cumulative culture.

Cultural transmission in an ever-changing world: trial-and-error copying may be more robust than precise imitation

Cultural transmission facilitates the spread of behaviours within social groups and may lead to the establishment of stable traditions in both human and non-human animals. The fidelity of transmission is frequently emphasized as a core component of cultural evolution and as a prerequisite for cumulative culture. Fidelity is often considered a synonym of precise copying of observed behaviours. However, while precise copying guarantees reliable transmission in an ideal static world, it may be vulnerable to realistic variability in the actual environment. Here, we argue that fidelity may be more naturally achieved when the social learning mechanisms incorporate trial-and-error; and that the robustness of social transmission is thereby increased. We employed a simple model to demonstrate how culture that is produced through exact copying is fragile in an (even slightly) noisy world. When incorporating a certain degree of trial-and-error, however, cultures are more readily formed in a stochastic environment and are less vulnerable to rare ecological changes. We suggest that considering trial-and-error learning as a stabilizing component of social transmission may provide insights into cultural evolution in a realistic, variable, world.This article is part of the theme issue 'Bridging cultural gaps: interdisciplinary studies in human cultural evolution'.

Social information can potentiate understanding despite inhibiting cognitive effort

Both reasoning ability and social learning play a crucial role in human adaptation. Cognitive abilities like enhanced reasoning skills have combined with cumulative cultural adaptation to allow our species to dominate the world like no other. Thus, understanding how social learning interacts with individual reasoning ability is crucial for unravelling our evolutionary history. Here we describe a laboratory experiment designed to investigate the effect of social learning on individuals’ ability to infer a general rule about unfamiliar problems. In this experiment, social information had both positive and negative effects on individuals’ likelihood of inferring the rule. Social learners required more evidence to infer the rule than did individual learners, suggesting that social learning inhibits cognitive effort but social learning provided individuals with information that individual learners were unlikely to gather on their own, especially as the task became more difficult. When individuals are unlikely to discover useful information by themselves, social learning can potentiate understanding even though it reduces individual cognitive effort.

Storytelling as Adaptive Collective Sensemaking

Storytelling represents a key element in the creation and propagation of culture. Three main accounts of the adaptive function of storytelling include (a) manipulating the behavior of the audience to enhance the fitness of the narrator, (b) transmitting survival‐relevant information while avoiding the costs involved in the first‐hand acquisition of that information, and (c) maintaining social bonds or group‐level cooperation. We assess the substantial evidence collected in experimental and ethnographic studies for each account. These accounts do not always appeal to the specific features of storytelling above and beyond language use in general. We propose that the specific adaptive value of storytelling lies in making sense of non‐routine, uncertain, or novel situations, thereby enabling the collaborative development of previously acquired skills and knowledge, but also promoting social cohesion by strengthening intragroup identity and clarifying intergroup relations.

Bietti, Tilston and Bangerter take an evolutionary approach towards memory transmission and storytelling, arguing that storytelling plays a central role in the creation and transmission of cultural information. They suggest that storytelling is a vehicle to transmit survival‐related information that helps to avoid the costs involved in the first‐hand acquisition of that information and contributes to the maintenance of social bonds and group‐level cooperation. Furthermore, Bietti et al. argue that, going beyond storytelling’s individualist role of manipulating the audience to enhance fitness of the narrator, that these adaptive functions of storytelling may well be assigned to other forms of language use besides narration (e.g., instructional discourse and argumentation). Based on this evidence, Bietti and colleagues claim that the specific adaptive function of storytelling lies in making sense of non‐routine, uncertain, or novel situations, thereby enabling collective sensemaking.

Mental template matching is a potential cultural transmission mechanism for New Caledonian crow tool manufacturing traditions

Cumulative cultural evolution occurs when social traditions accumulate improvements over time. In humans cumulative cultural evolution is thought to depend on a unique suite of cognitive abilities, including teaching, language and imitation. Tool-making New Caledonian crows show some hallmarks of cumulative culture; but this claim is contentious, in part because these birds do not appear to imitate. One alternative hypothesis is that crows’ tool designs could be culturally transmitted through a process of mental template matching. That is, individuals could use or observe conspecifics’ tools, form a mental template of a particular tool design, and then reproduce this in their own manufacture – a process analogous to birdsong learning. Here, we provide the first evidence supporting this hypothesis, by demonstrating that New Caledonian crows have the cognitive capacity for mental template matching. Using a novel manufacture paradigm, crows were first trained to drop paper into a vending machine to retrieve rewards. They later learnt that only items of a particular size (large or small templates) were rewarded. At test, despite being rewarded at random, and with no physical templates present, crows manufactured items that were more similar in size to previously rewarded, than unrewarded, templates. Our results provide the first evidence that this cognitive ability may underpin the transmission of New Caledonian crows’ natural tool designs.

Young children fail to generate an additive ratchet effect in an open-ended construction task

The ratchet effect-the gradual accumulation of changes within a cultural trait beyond a level that individuals can achieve on their own-arguably rests on two key cognitive abilities: high-fidelity social learning and innovation. Researchers have started to simulate the ratchet effect in the laboratory to identify its underlying social learning mechanisms, but studies on the developmental origins of the ratchet effect remain sparse. We used the transmission chain method and a tower construction task that had previously been used with adults to investigate whether "generations" of children between 4 and 6 years were able to make a technological product that individual children could not yet achieve. 21 children in a baseline and 80 children in transmission chains (each consisting of 10 successive children) were asked to build something as tall as possible from plasticine and sticks. Children in the chains were presented with the constructions of the two preceding generations (endstate demonstration). Results showed that tower heights did not increase across the chains nor were they different from the height of baseline towers, demonstrating a lack of improvement in tower height. However, we found evidence for cultural lineages, i.e., construction styles: towers within chains were more similar to each other than to towers from different chains. Possible explanations for the findings and directions for future research are suggested.