Despite promising a “unified account” of culture, the authors neglect to define what they take culture to encompass. Because they cite Henrich (Reference Henrich2015) with approval, perhaps we can borrow his definition of culture as “the large body of practices, techniques, heuristics, tools, motivations, values and beliefs that we all acquire while growing up, mostly by learning from other people” (p. 3). Substituting “individuals” for “people,” culture thus defined has been discovered to be widespread among non-human animals (henceforth “animals”) (Whiten Reference Whiten2017a). Yet, it receives virtually no mention in the target article. This lacuna contrasts starkly with another recent peer-commentary articles offering broad theories of culture (Tamariz Reference Tamariz2019; Osiurak & Reynaud Reference Osiurak and Reynaud2020) that do incorporate core animal literature (I note there is virtually no overlap in the sources cited in these theoretical offerings!). Here, I outline dimensions of animal culture that I suggest any unifying account of culture must recognize.

First, phylogenetic reach. Traditions meeting the above specifications have been identified in hundreds of studies of mammals (particularly primates [Whiten & van de Waal Reference Whiten and van de Waal2018] and cetaceans [Whitehead & Rendell Reference Whitehead and Rendell2015]) as well as birds (Aplin Reference Aplin2019), and fish (Laland et al. Reference Laland, Atton and Webster2011). Transmission chain experiments have demonstrated inheritance across multiple “cultural generations” (i.e., from individual or group A, to B to C, etc.); the content of these ranges from foraging techniques in chimpanzees and children (Horner et al. Reference Horner, Whiten, Flynn and de Waal2006) to those of bumble bees (Alem et al. Reference Alem, Perry, Zhu, Loukola, Ingraham, Søvik and Chittka2016) and mate choice preferences in fruit flies (Danchin et al. Reference Danchin, Nöbel, Pocheville, Dagaeff, Demay, Alphand, Ranty-Roby, van Renssen, Monier, Gazagne, Allain and Isabel2018; Whiten Reference Whiten2018a).

Second is intra-species pervasiveness. Whitehead and Rendell (Reference Whitehead and Rendell2015, p. 17) conclude from their book-length survey that “culture, we believe, is a major part of what the whales are.” Whiten and van de Waal (Reference Whiten and van de Waal2018) distinguish three main phases of cultural acquisition in primates: first, juveniles learn much about foraging and other activities from their mother, whom they may accompany closely for years; in a second phase learning expands to a wider social circle, when young males may apprentice themselves to adult males who exploit a somewhat different cultural foraging niche than their mothers; and finally, in a third phase dispersing individuals learn from individuals in their new group who are already informed about local resources and group dynamics. Schuppli and van Schaik (Reference Schuppli and van Schaik2019) and Whiten (Reference Whiten2019a; Reference Whiten2019b; Reference Whiten2019c) infer from records of juvenile orangutans’ close peering at adult activities that the number of behaviours so learned may exceed 190. “It seems that immatures learn virtually all of their skills socially,” they conclude (p. 5). What animals learn from the accumulated knowledge of conspecifics spans dietary profiles, foraging techniques, predator avoidance, mate choice, courtship behaviour, vocal communication, migration routes, tool use, social customs, circadian rhythms, and locomotion styles.

These varied domains of social learning raise the prospect that animal cultures may be constituted of multiple traditions, paralleling the way we refer to a whole array of traditions (technologies, diet, communications, etc.) when we contrast any two human cultures (Whiten & van Schaik Reference Whiten and van Schaik2007). Such patterning, including regional cultural variations, has so far appeared most extensive in great apes (Schuppli & van Schaik Reference Schuppli and van Schaik2019; Whiten Reference Whiten2017b) but has also been documented in cetaceans (Whitehead & Rendell Reference Whitehead and Rendell2015) and likely applies to many birds where traditions span such diverse contexts as song dialects, migration, and foraging (Aplin Reference Aplin2019). Veissière et al. state that “it is precisely because of the existence of inter group behavioural and cognitive variations that arise through social learning … that we can speak of culture” – but surely not: certainly Henrich's definition does not require this. A universal behaviour would still be cultural, if routinely acquired by social learning from others (Schuppli & van Schaik Reference Schuppli and van Schaik2019).

A third important discovery about animal cultures concerns stability and fidelity over time. Archaeological excavations revealed chimpanzee nut-cracking technologies based on natural stone hammers at a level corresponding to 4,300 years ago, at sites where the skill still occurs today (Mercader et al. Reference Mercader, Barton, Gillisepie, Harris, Kuhn, Tyler and Boesch2007). How many contemporary human traditions have shown such fidelity over this period? Cultural changes can also be quite rapid, an important characteristic of this “second inheritance system” in nature, contrasting with the primary inheritance system of genetics, that is less nimble (Whiten Reference Whiten2017a). Humpback whale songs, for example, rise in objectively measurable complexity over time, then every few years the currently common song is superseded by a new “revolutionary” but simpler song, soon adopted by the whole population (Allen et al. Reference Allen, Garland, Dunlop and Noad2018). Such new songs are known to be passed across the Pacific Ocean populations over a period of years, to be followed by further waves of new songs as these emerge.

A fourth major discovery has concerned adaptive preferences guiding animals’ social learning. Veissière et al. focus much on adaptive attentional funnelling in the context of human culture, but this also occurs in animals, using a variety of cues that allow social learning to deviate from randomly copying others and achieve adaptive selectivity (Kendal et al. Reference Kendal, Boogert, Rendell, Laland, Webster and Jones2018; Price et al. Reference Price, Wood and Whiten2017). These cues are diverse but span some that Veissière et al. discuss in the human case. They include conformity, expressed as a motivation to do what a majority of one's companions do (Aplin et al. Reference Aplin, Farine, Morand-Ferron, Cockburn, Thornton and Sheldon2015; Watson et al. Reference Watson, Lambeth, Schapiro and Whiten2018; Whiten Reference Whiten2019c for avian and primate examples, respectively). Other biases include copying high ranking and more successful individuals (Bono et al. Reference Bono, Whiten, van Schaik, Krutzen, Eichenberger, Schnider and van de Waal2018; Kendal et al. Reference Kendal, Hopper, Whiten, Brosnan, Lambeth, Schapiro and Hoppitt2015). The latter study illustrates how complex combinations of preferences may arise: vervet monkeys’ selectivity depends not only on the relative foraging payoffs they observe accruing to others, but also on the sex of the observer and the sex of the forager observed. Preferential learning from high rankers may sometimes be more akin to prestige effects in humans than often asserted; lemurs who were more successful at a novel foraging opportunity have been shown to receive more affiliative responses from companions later (Kulahci et al. Reference Kulahci, Ghazanfar and Rubenstein2018; Whiten Reference Whiten2018b).

The above can be no more than a selective sketch of recent discoveries about animal cultures. But, these phenomena surely enrich our understanding of the nature and evolution of culture: A unified theory of culture must surely accommodate them?