Learning how to use a tool: Mutually exclusive tool-function mappings are selectively acquired from linguistic in-group models

Preschoolers retain more details from event sequences 1 week following an in-group demonstration

Previous research highlights that the learning processes of preschool-aged children are influenced by the cultural group membership of the information sources. As of yet, however, no study has aimed to explore the influence of cultural group membership on the long-term retention of novel information. In the current study, 4-year-old children observed three event sequences that were demonstrated by either an adult speaking their native language or a foreign language speaker. In Experiment 1, children (N = 56) were allowed to imitate the events immediately. Results showed that the average number of accurately reproduced details (native = 3.26; foreign = 3.11) and the order of event elements (native = 1.69; foreign = 1.49) did not significantly differ in the two conditions. In Experiment 2, children (N = 56) were allowed to imitate only following a 1-week delay. In this case, children retained more details (native = 2.6; foreign = 2.2) and reproduced the order in the event sequences more accurately (native = 1.18; foreign = 0.87) following a native demonstration. The behavior of children in all conditions differed from a baseline group without any instruction (n = 15). These findings show that preschoolers retain more information in the long term when it was demonstrated to them by a member of their own culture. Importantly, they also learn from people belonging to different cultures-as evidenced by both the lack of difference in Experiment 1 and the difference between the out-group condition of Experiment 2 and the baseline.

The Icing on the Cake. Or Is it Frosting? The Influence of Group Membership on Children's Lexical Choices

Adults are skilled at using language to construct/negotiate identity and to signal affiliation with others, but little is known about how these abilities develop in children. Clearly, children mirror statistical patterns in their local environment (e.g., Canadian children using zed instead of zee), but do they flexibly adapt their linguistic choices on the fly in response to the choices of different peers? To address this question, we examined the effect of group membership on 7- to 9-year-olds' labeling of objects in a trivia game, exploring whether they were more likely to use a particular label (e.g., sofa vs. couch) if members of their "team" also used that label. In a preregistered study, children (N = 72) were assigned to a team (red or green) and were asked during experimental trials to answer questions-which had multiple possible answers (e.g., blackboard or chalkboard)-after hearing two teammates and two opponents respond to the same question. Results showed that children were significantly more likely to produce labels less commonly used by the community (i.e., dispreferred labels) when their teammates had produced those labels. Crucially, this effect was tied to group membership, and could not be explained by children simply repeating the most recently used label. These findings demonstrate how social processes (i.e., group membership) can guide linguistic variation in children.

Children Treat Grammatical Errors Differently for Native and Non-Native Speakers

Both children and adults demonstrate biases against non-native speakers. However, in some situations, adults act more generously towards non-native speakers than towards native speakers. In particular, adults judge errors from non-native speakers less harshly, presumably because they expect such errors. In the present study, we asked whether 5-6-year-old children place less weight on errors from speakers with a foreign accent. In Experiment 1, 5- and 6-year-old children (N = 80) listened to pairs of either native or foreign-accented speakers (between-subjects) label objects. For native speaker pairings, children preferred information provided by grammatical speakers over information from speakers who made subject-verb agreement errors. In contrast, children chose between foreign-accented speakers at chance. In Experiment 2 (N = 40), children preferred information from grammatical foreign-accented speakers over information from foreign-accented speakers who produced word-order violations. These findings constitute the first demonstration that children treat speech errors differently based on a speaker’s language background.

Copy the In-group: Group Membership Trumps Perceived Reliability, Warmth, and Competence in a Social-Learning Task

Surprisingly little is known about how social groups influence social learning. Although several studies have shown that people prefer to copy in-group members, these studies have failed to resolve whether group membership genuinely affects who is copied or whether group membership merely correlates with other known factors, such as similarity and familiarity. Using the minimal-group paradigm, we disentangled these effects in an online social-learning game. In a sample of 540 adults, we found a robust in-group-copying bias that (a) was bolstered by a preference for observing in-group members; (b) overrode perceived reliability, warmth, and competence; (c) grew stronger when social information was scarce; and (d) even caused cultural divergence between intermixed groups. These results suggest that people genuinely employ a copy-the-in-group social-learning strategy, which could help explain how inefficient behaviors spread through social learning and how humans maintain the cultural diversity needed for cumulative cultural evolution.

One Function One Tool? A Review on Mutual Exclusivity in Tool Use Learning in Human and Non-human Species

The goal of this review is twofold: first to explore whether mutual exclusivity and functional fixedness overlap and what might be their respective specificities and second, to investigate whether mutual exclusivity as an inferential principle could be applied in other domains than language and whether it can be found in non-human species. In order to do that, we first give an overview of the representative studies of each phenomenon. We then analyze papers on tool use learning in children that studied or observed one of these phenomena. We argue that, despite their common principle -one tool one function- mutual exclusivity and functional fixedness are two distinct phenomena and need to be addressed separately in order to fully understand the mechanisms underlying social learning and cognition. In addition, mutual exclusivity appears to be applicable in other domains than language learning, namely tool use learning and is also found in non-human species when learning symbols and tools.

Two-Year-Old Children Expect Native, but Not Foreign Speakers to Use the Same Tool for the Same Purpose

Previous research has already demonstrated that even very young children are sensitive to language cues and learn differently from native and foreign speaker models. A possible explanation for this phenomenon suggests that spoken language is a sign of someone's cultural background and in this sense demonstrates the person's culture specific knowledge. The aim of the present study was to investigate what children think about native and foreign speakers' behavior in a domain that is typically regulated by cultural norms (tool usage), specifically whether they expect group members to act alike or not. In a violation of expectation paradigm, two-year-old toddlers first watched a video on which a native and a foreign speaker person used different tools for achieving the same goal. In the test phase a new native speaker model appeared and selected one of the previously seen tools for the same goal as it was used before. Results indicated that toddlers were surprised if the native speaker model had chosen the tool that had previously been used by the foreign speaker. In Experiment 2, the familiarization phase was exactly the same as in Experiment 1, but during the test phase, the model spoke a foreign language. Results, in this case, showed no significant differences between looking times. These experiments suggest that two-year-olds expect native (but not foreign) speakers to use the same tool for the same goals. As tool usage is a fundamental element of cultural knowledge, we propose that this pattern of results suggest that children expect native speakers to possess shared cultural knowledge at least in the domain of artifacts.

Social categorization based on permanent versus transient visual traits in neurotypical children and children with autism spectrum disorder

The present study was designed to test the relative weight of different types of category markers in children's representations of social and biological kinds. We reasoned that in order to efficiently navigate through the mesh network of overlapping social categories, the representational system dedicated to processing information about social groups should be prepared to flexibly switch between potential ways of categorizing fellow humans. Thus, we hypothesized that children would assign more relevance to transient but symbolic features, such as shirt colour, when categorizing humans than other animal species. Across two experiments, we investigated whether typically developing children as well as children diagnosed with Autism Spectrum Disorder would categorize drawings of humans and dogs along a transient or a biologically set, permanent marker. The results show that both groups of children overwhelmingly selected the permanent feature to categorize dogs, however, they were more likely to categorize fellow humans based on transient features. We suggest that this tendency lays the ground for humans' ability to efficiently represent the complex structure of societies.

Obtaining new resolutions in carnivore tooth pit morphological analyses: A methodological update for digital taphonomy

Modern day investigation in fields of archaeology and palaeontology can be greatly characterised by an exponential growth of integrated new technologies, nevertheless, while these advances are of great significance to multiple lines of research, their evaluation and update over time is equally as important. Here we present an application of inter and intra-observer analysis in taphonomy based geometric morphometrics, employing robust non-parametric statistical analyses for the study of experimental carnivore tooth pit morphologies. To fully understand the influence of measurement errors in the collection of this data, our statistical assessment was performed on fully superimposed, partially superimposed and raw landmark coordinates collected from 3D surface scanning. Experimental samples used to assess these errors includes wolf and dog tooth pits used in modern day ecological livestock predation analysis. Results obtained from this study highlight the importance of landmark type in the assessment of error, emphasising the value of semi-landmark models over the use of ambiguous Type III landmarks. In addition to this, data also reveals the importance of observer experience for the collection of data alongside an interesting increase in error when working with fully superimposed landmarks due to the “Pinocchio Effect”. Through this study we are able to redefine the geometric morphometric models used for tooth pit morphological analyses. This final hybrid Type II fixed landmark and semi-landmark model presents a significant reduction in human induced error, generating a more metrically reliable and replicable method that can be used for data pooling in future inter-institutional research. These results can be considered a fundamental step forward for carnivore inspired studies, having an impact on archaeological, palaeontological, modern-day ecological research as well as applications in other forensic sciences.