Lew-Levy & Amir compellingly argue for the critical role of human children in cultural adaptation. We agree, but pushing the argument further back in evolutionary time, we propose that cultural innovation and transmission among infants are not uniquely human. Twentieth-century studies challenge the idea that culture is exclusive to humans (Galef, Reference Galef1992; Laland & Hoppitt, Reference Laland and Hoppitt2003; Whiten, Reference Whiten2021). Animal culture, shaped by species-specific traits and ecological contexts, has emerged as a field of study (Huffman & Hirata, Reference Huffman, Hirata, Fragaszy and Perry2003). Our commentary extends this discussion by highlighting that nonhuman animals also exhibit culture. In these species groups as well, the young often act as key cultural agents, as innovators and early adopters of new behaviors.

The discovery of animal culture was first made in Japanese macaques, notably Imo, a juvenile female observed washing sweet potatoes on the beach of Koshima Island, an innovation later adopted by many in her group (Hirata, Watanabe, & Masao, Reference Hirata, Watanabe, Masao and Matsuzawa2001; Kawai, Reference Kawai1965; Matsuzawa, Reference Matsuzawa2015b). This behavior, along with wheat washing, marked early evidence of social transmission. Other cultural behaviors include stone handling, initiated by a juvenile female, and transmitted horizontally among peers, then vertically from mothers to offspring (Huffman, Reference Huffman1996; Leca, Gunst, & Huffman, Reference Leca, Gunst and Huffman2007; Nahallage & Huffman, Reference Nahallage and Huffman2007), and hot spring bathing, which reduces stress and enhances thermoregulation (Matsuzawa, Reference Matsuzawa2018; Suzuki, 1965; Takeshita et al., Reference Takeshita, Bercovitch, Kinoshita and Huffman2018). These behaviors reveal culture-like processes across macaque populations. This is now extended to many animal species, even insects. Animal culture refers to socially learned behaviors transmitted horizontally and vertically within species (Galef, Reference Galef1992; Laland & Hoppitt, Reference Laland and Hoppitt2003; Whiten, Reference Whiten2021), the direction being dependent in part by the nature of the behavior itself (Huffman & Hirata, Reference Huffman, Hirata, Fragaszy and Perry2003). These behaviors, not genetically inherited, vary across populations and are shaped by social transmission rather than environmental factors alone (Hoppitt & Laland, Reference Hoppitt and Laland2013; Whiten, Reference Whiten2000). However, similar behaviors found in isolated populations, and indeed phylogenetically related taxa suggest a complex interplay between genetic predispositions and learning (Huffman & Hirata, Reference Huffman, Hirata, Fragaszy and Perry2003). Transmission mechanisms include local enhancement, imitation, and even teaching (Galef & Heyes, Reference Galef and Heyes2004; Zentall, Reference Zentall2022). Cultural diversity, as seen in chimpanzee tool use (Whiten, Horner, & de Waal, Reference Whiten, Goodall, McGrew, Nishida, Reynolds, Sugiyama, Tutin, Wrangham and Boesch1999, Reference Whiten, Horner and de Waal2005), challenges the human exclusivity of culture and enriches our understanding of evolutionary processes. Researchers distinguish between preculture, protoculture, and culture to reflect varying levels of behavioral complexity in animals (Laland, Reference Laland, Akazawa, Aoki and Bar-Yosef1998; McGrew, Reference McGrew1998; Tonutti, Reference Tonutti2011). Preculture includes early-stage, inconsistently transmitted behaviors, often arising from imitation or trial-and-error. Protoculture involves socially learned behaviors, like tool use in chimpanzees or sweet potato washing in macaques, transmitted across generations but lacking symbolic and cumulative features (Asquith, Reference Asquith2003; Matsuzawa, Reference Matsuzawa2015a, Reference Matsuzawa2015b). In contrast, human culture is cumulative and symbolic, enabled by language, abstract thought, and teaching (Dean et al., Reference Dean, Vale, Laland, Flynn and Kendal2014; Mesoudi & Thornton, Reference Mesoudi and Thornton2018). It even includes externalized cognition through tools like smartphones (Clark & Chalmers, Reference Clark and Chalmers1998; Henrich, Reference Henrich2017).

However, in many animal species, we can observe infants as learners and innovators in cultural transmission. What about learning? In chimpanzees, nut-cracking, a behavior requiring the selection and use of stones or wood to open hard-shelled nuts, is socially learned through prolonged observation and practice (about ten years) during infancy (Biro, Sousa, & Matsuzawa, Reference Biro, Sousa and Matsuzawa2006; McGrew et al., Reference McGrew, Ham, White, Tutin and Fernandez1997). Young individuals often imitate skilled adults, especially their mothers, in both technique and tool choice. Killer whale caves also spend years learning particularly complex hunting strategies like intentional stranding or coordinated attacks on seals by shadowing their matrilineal group, where mothers and grandmothers act as cultural guides and teachers (Lopez & Lopez, Reference Lopez and Lopez1985; Visser et al., Reference Visser, Smith, Bullock, Green, Carlsson and Imberti2008). In meerkats, adults gradually introduce pups to prey by initially providing incapacitated scorpions, adjusting the level of difficulty of the task as the young mature (Thornton & McAuliffe, Reference Thornton and McAuliffe2006). Similarly, juvenile New Caledonian crows acquire complex tool-making skills, such as crafting hooked twigs, by observing experienced adults, with population-level variation indicating local cultural traditions (Hunt, Reference Hunt1996; Hunt & Gray, Reference Hunt and Gray2003; Rutz, Hunt, & Clair, Reference Rutz, Hunt and Clair2018). These examples highlight the significance of an early age in acquiring survival skills and sustaining cultural continuity across generations.

Animal young are not only learners but also powerful innovators in the emergence of animal culture. A striking example is Imo, a juvenile female Japanese macaque who, in 1953, initiated sweet potato washing on Koshima Island, a behavior never observed before (Hirata et al., Reference Hirata, Watanabe, Masao and Matsuzawa2001; Matsuzawa, Reference Matsuzawa2015b). Her innovation quickly spread among peers, especially juveniles, before being adopted by some adults (Kawai, Reference Kawai1965). Imo also contributed to wheat washing behavior, demonstrating creative problem-solving to separate wheat grains from sand. In other macaque populations, stone handling (SH) – a complex and nonfunctional behavior comprising dozens of distinct manipulations – also originated with a juvenile and spread horizontally to peers before being passed vertically from SH mothers to offspring when they began to raise their own offspring (Huffman, Reference Huffman1996; Leca et al., Reference Leca, Gunst and Huffman2007; Nahallage & Huffman, Reference Nahallage and Huffman2007), showing the importance of peer culture. In orangutans and capuchins, young individuals experiment with tools and materials, occasionally inventing new foraging techniques (Fox, Sitompul, & Van Schaik, Reference Fox, Sitompul and Van Schaik1999; Fragaszy et al., Reference Fragaszy, Izar, Visalberghi, Ottoni and de Oliveira2004). Juvenile dolphins have been observed to initiate playful or tool-based foraging strategies, such as sponge-carrying, later adopted by others (Mann et al., Reference Mann, Sargeant, Watson-Capps, Gibson, Heithaus, Connor and Patterson2008). Even in birds like New Caledonian crows, young individuals display exploratory behavior that can lead to innovations in tool manufacture (Hunt, Reference Hunt1996). Across taxa, young individuals emerge as essential drivers of cultural novelty and transmission.

Recognizing the agency (Sueur, Zanaz, & Pelé, Reference Sueur, Zanaz and Pelé2023) of young animals in cultural transmission has practical implications for research and conservation. Infants naturally observe their mothers and peers from birth, eliminating the need for artificial training in experimental tasks. This offers a unique window into spontaneous cultural learning and supports the integration of co-culture approaches in human-animal interactions (Sueur & Huffman, Reference Sueur and Huffman2024). As Lew-Levy & Amir emphasize for humans, acknowledging juvenile roles enriches our understanding of cultural dynamics. Preserving animal cultures, as forms of biodiversity and adaptive knowledge, thus becomes essential for both scientific insight and conservation ethics (Sueur, Reference Sueur2022; Sueur, Fourneret, & Espinosa, Reference Sueur, Fourneret and Espinosa2024).