Bard et al.’s article tackles timely and pertinent issues regarding the lack of inclusivity in developmental science. We agree that pervasive Western-centric biases have shaped and sometimes even distorted theoretical models of human development. Cultural marginalisation of non-Western samples is hampering progress, and a radical new approach, which embeds diversity and inclusivity, is needed to advance current understanding of human development.

Although we find the acronym itself problematic, we support the principles of the WILD framework (Newson et al., Reference Newson, Buhrmester, Xygalatas and Whitehouse2021), that developmental research should be Worldwide, in Situ, Local and with Diverse populations. However, we suggest that the authors have nevertheless omitted a core foundation for their framework: evolution. Evolutionary theory is crucial for theory-building, offering a base upon which subsequent layers of the WILD framework can be built.

Using cross-cultural and comparative evidence, the authors critique two key developmental theories, Shared Intentionality theory and Attachment theory, and put forward a strong case against Western-biased models of human social development. While comparative evidence is used to support their case, especially against Shared Intentionality Theory, we recommend embedding evolutionary perspectives more deeply in their framework to strengthen developmental theory-building.

Shared Intentionality Theory (Tomasello et al., Reference Tomasello, Carpenter, Call, Behne and Moll2005, Tomasello, Reference Tomasello2019) receives the lion’s share of the attack, somewhat affecting balance. The authors challenge claims that shared intentionality is uniquely human and that it is a human universal. We agree that comparative research shows that some forms of shared intentionality are observable in other species, particularly great apes. This is echoed by a growing comparative literature on social action coordination and triadic engagement (Heesen & Frolich, Reference Heesen and Fröhlich2022).

Bard et al. also present convincing cross-cultural evidence of rich and diverse forms of interactional exchange beyond conversational turn-taking. Nevertheless, an evolutionary perspective aligns conversational turn-taking as a core feature of human social interaction. As a species with rich social dynamics involving complex social interactions with both in- and out-groups, this capacity facilitates rapid information exchange, not only linguistically but also for other forms of cultural transmission and social interaction too. Comparative evidence suggests this capacity has deep evolutionary roots, with key elements of conversational turn-taking observable in other great apes and other species too (Abreu & Pika, Reference Abreu and Pika2022).

The authors highlight the presence of other vocal interactional styles, including cross-talking and synchronisation, aligning with the cultural values of unity and inter-dependence more common in Majority-world settings. Evolutionary accounts also emphasise the important role that synchronisation and polyphony play in our lineage’s communicative and bonding toolkit. There is evidence, for example, of conserved traits of human musicality observable in other ape species (Brooks et al., Reference Brooks, Clay, Dufour, Fedurek, Girard-Buttoz and Yamamoto2025). A bottom-up evolutionary view thus complements our species-rich cross-cultural diversity, supports the roles of both turn-taking and synchrony in our species’ evolution.

Turning to Attachment Theory, inclusion of comparative evidence is largely and surprisingly absent here, despite its evident relevance. The authors highlight the remarkable flexibility in human attachment dynamics, including the overlooked role of attachment networks (Forslund et al., Reference Forslund, Granqvist, van IJzendoorn, Sagi-Schwartz, Glaser and Steele2022; Funk et al., 2022). While Attachment Theory may have over-focussed on the mother-offspring attachment relationship while ignoring others, we argue that this is most likely an ancestral trait from which human attachment networks derived, given that for all four extant non-human great apes, mothers are the majority carer of infants. Unlike other known great apes, humans are considered to be cooperative breeders (Burkhart & van Schaik Reference Burkart and Van Schaik2016). Whether other species with cooperative breeding social systems, like some gibbon species, demonstrate similar attachment networks is an open question.

Attachment theory is based on Bowlby’s (Reference Bowlby1969) original idea that when under threat, it is adaptive for dependent offspring to approach carers, under the condition that carers increase their chances of safety. As caring is costly, carers are often parents who gain indirect benefits from offspring survival. In mammals, nursing often necessitates that mothers are the main carers. Mammalian neurobiology underpinning maternal nurturing and offspring response feedback loops, and subsequent offspring development, is highly conserved and can offer insights into the neurobiology of human attachment patterns informed by millions of years of evolution (Rilling & Young Reference Rilling and Young2014).

Drawing on this framework, new comparative evidence supports the importance of the mother-offspring relationship in shaping socio-emotional development. Recent research with wild chimpanzees in the Taï Chimpanzee Project, Ivory Coast, has provided striking evidence for the existence of organised attachment styles, which map onto those first proposed in Attachment Theory (Rolland et al., Reference Rolland, Nodé-Langlois, Tkaczynski, Girard-Buttoz, Rayson, Crockford and Wittig2025). For this observational study, the researchers adapted Ainsworth’s classic Strange Situation Procedure (SSP, Ainsworth et al., Reference Ainsworth, Blehar, Waters and Wall1978) to examine how mothers and their offspring responded to naturally occurring threatening events. This ecologically relevant setting addresses a critique of Bard et al. that the experimental SSP paradigm is ecologically invalid. Rolland et al. found evidence of two distinct attachment styles, corresponding to secure and insecure attachment styles, yet an absence of disorganised attachment styles, contrasting with studies with captive chimpanzees (Clay, Reference Clay2012). These comparative studies support the view that organised mother-offspring attachment types are adaptive.

Especially given the profound neurobiological underpinnings of mother-offspring relationships and nurturing care, it is fascinating that some human societies aim to culturally inhibit natural attachment processes by, for example, interrupting maternal-offspring eye contact during nursing, apparently with the aim to facilitate the engagement of multiple caregivers (Ndzenyuiy & Keller, Reference Ndzenyuiy, Keller and Verschurein press). What socio-ecological factors may influence divergences in human attachment styles requires further research.

In sum, a much richer understanding of both human and non-human attachment processes, as well as those related to shared intentionality, can be gained by combining the proposed cross-cultural WILD framework with a biological evolutionary perspective, compared with studying either process in isolation.