Teaching strategies are shaped by experience with formal education: Experimental evidence from caregiver-child dyads in two Tannese communities.

Humans are extraordinary in the extent to which we rely on cumulative culture to act upon and make sense of our environment. Teaching is one social learning process thought to be fundamental to the evolution of cumulative culture as a means of adaptation in our species. However, the frequency of teaching and how we teach are known to vary across human sociocultural contexts. Understanding this variation adds to our understanding of the complex interplay between cognition and culture in shaping learning behavior but also contributes to theory around the costs and benefits of different social learning processes. Here, we examined how prior experience with formal education is related to the frequency and diversity of teaching behaviors in an experimental paradigm where caregivers were motivated (but not instructed) to teach a simple skill to a child (7-10 years old). We identified and coded a suite of subtle nonverbal behaviors that could be construed as facilitating learning. Dyads (n = 64) were recruited from two communities on Tanna Island that differ in their experience with formal schooling and their acceptance of Western institutions. We found evidence for parallel teaching strategies in both communities. However, the rate and diversity of teaching behaviors were positively associated with caregiver's experience with formal schooling and independently and negatively associated with being from a village that rejects Western-derived institutions. These results further our understanding of how multiple cultural processes influence social learning and highlights the powerful influence of formal schooling on the cultural evolution of teaching in humans.

Variation in caregivers' references to their toddlers: Child-directed speech in Vanuatu and Canada.

The authors examined similarities and differences in Canadian and ni-Vanuatu caregivers' child-directed speech to their toddlers (N = 35, Mage : 21 months, 20 girls). Speech samples were collected (2013-2016) during free play and analyzed with a focus on describing parents' references to their toddlers. Canadian caregivers referred significantly more to toddlers' tangible characteristics (relative risk, RR = 2.12) and internal states (RR = 2.31), whereas ni-Vanuatu caregivers referred more to actions (RR = 2.04). When referring to internal states, Canadian mothers referred significantly more to mind-minded states, whereas ni-Vanuatu caregivers referred more to body-minded states (RR = 7.98). These findings are interpreted as capturing meaningful differences in toddlers' opportunities to attend to themselves. Implications for self-concept development are discussed.

Rethinking the phonetics of baby-talk: Differences across Canada and Vanuatu in the articulation of mothers' speech to infants.

Infant-directed speech (IDS) is phonetically distinct from adult-directed speech (ADS): It is typically considered to have special prosody-like higher pitch and slower speaking rates-as well as unique speech sound properties, for example, more breathy, hyperarticulated, and/or variable consonant and vowel articulation. These phonetic features are widely observed in the IDS of caregivers from urbanized contexts who speak a handful of very well-researched languages. Yet studies with more diverse socio-cultural and linguistic samples show that this "typical" IDS prosody is not consistently observed across cultures. We extended cross-cultural work by examining IDS speech segment articulation, which-like prosody-is also thought to be a characteristic phonetic feature of IDS that might aid speech and language development. Here we asked whether IDS vowels have different articulatory features compared to ADS vowels in two distinct linguistic and socio-cultural contexts: urban English-speaking Canadian mothers, and rural Lenakel- and Southwest Tanna-speaking ni-Vanuatu mothers (n = 57, 20-46 years of age). Replicating prior work, Canadian mothers had more variable vowels in IDS compared to ADS, but also did not show clear register differences for breathiness or hyperarticulation. Vowels spoken by ni-Vanuatu mothers showed very distinct articulatory tendencies, using less variable (and less breathy) IDS vowels. Along with other work showing diversity in IDS phonetics across populations, this paper suggests that any understanding of how IDS might aid speech and language development are best examined through a culturally- and linguistically-specific lens.

Explaining cross-cultural variation in mirror self-recognition: New insights into the ontogeny of objective self-awareness.

Mirror self-recognition (MSR) is considered to be the benchmark of objective self-awareness-the ability to think about oneself. Cross-cultural research showed that there are systematic differences in toddlers' MSR abilities between 18 and 24 months. Understanding whether these differences result from systematic variation in early social experiences will help us understand the processes through which objective self-awareness develops. In this study, we examined 57 18- to 22-month-old toddlers (31 girls) and their mothers from two distinct sociocultural contexts: urban Canada (58% of the subsample were Canadian-born native English-speakers) and rural Vanuatu, a small-scale island society located in the South Pacific. We had two main goals: (a) to identify the social-interactional correlates of MSR ability in this cross-cultural sample, and (b) to examine whether differences in passing rates could be attributed to confounding factors. Consistent with previous cross-cultural research, ni-Vanuatu toddlers passed the MSR test at significantly lower rates (7%) compared to their Canadian counterparts (68%). Among a suite of social interactive variables, only mothers' imitation of their toddlers' behavior during a free play session predicted MSR in the entire sample and maternal imitation partially mediated the effects of culture on MSR. In addition, low passing rates among ni-Vanuatu toddlers could not be attributed to reasons unrelated to self-development (i.e., motivation to show mark-directed behavior, understanding mirror-correspondence, representational thinking). This suggests that differences in MSR passing rates reflect true differences in self-recognition, and that parental imitation may have an important role in shaping the construction of visual self-knowledge in toddlers. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Opportunities for Interaction : Natural Observations of Children's Social Behavior in Five Societies.

We examine the opportunities children have for interacting with others and the extent to which they are the focus of others' visual attention in five societies where extended family communities are the norm. We compiled six video-recorded datasets (two from one society) collected by a team of anthropologists and psychologists conducting long-term research in each society. The six datasets include video observations of children among the Yasawas (Fiji), Tanna (Vanuatu), Tsimane (Bolivia), Huatasani (Peru), and Aka (infants and children 4-12 years old; Central African Republic). Each dataset consists of a series of videos of children ranging in age from 2 months to 12 years in their everyday contexts. We coded 998 videos and identified with whom children had opportunities to interact (male and female adults and children) as well as the number of individuals and the proportion of observed time that children spent with these individuals. We also examined the proportion of time children received direct visual gaze (indicating attention to the child). Our results indicate that children less than 5 years old spend the majority of their observed time in the presence of one female adult. This is the case across the five societies. In the three societies from which we have older children (Aka, Yasawa, Peru), we find a clear shift around 5 years of age, with children spending the majority of their time with other children. We also coded the presence or absence of a primary caregiver and found that caregivers remained within 2 ft of target children until 7 years of age. When they were in the company of a primary caregiver, children older than seven spent the majority of their time more than 2 ft from the caregiver. We found a consistent trend across societies with decreasing focal attention on the child with increasing child age. These findings show (1) remarkable consistency across these societies in children's interaction opportunities and (2) that a developmental approach is needed to fully understand human development because the social context is dynamic across the lifespan. These data can serve as a springboard for future research examining social development in everyday contexts.

Universal norm psychology leads to societal diversity in prosocial behaviour and development.

Recent studies have proposed that social norms play a key role in motivating human cooperation and in explaining the unique scale and cultural diversity of our prosociality. However, there have been few studies that directly link social norms to the form, development and variation in prosocial behaviour across societies. In a cross-cultural study of eight diverse societies, we provide evidence that (1) the prosocial behaviour of adults is predicted by what other members of their society judge to be the correct social norm, (2) the responsiveness of children to novel social norms develops similarly across societies and (3) societally variable prosocial behaviour develops concurrently with the responsiveness of children to norms in middle childhood. These data support the view that the development of prosocial behaviour is shaped by a psychology for responding to normative information, which itself develops universally across societies.