Written by: Damien Neadle and Claudio Tennie
Culture is all around us, from the device that you are seeing/hearing this on to the very words I am using. However, it is a rather slippery fish to grasp and it can be difficult to nail down exactly what culture is.
When I say “culture” what do you think of? I expect that this will vary depending on who you are: a biologist might think of something close to the definition provided by the Oxford English Dictionary (2019):
“The cultivation of bacteria, tissue cells, etc. in an artificial medium containing nutrients”
An anthropologist might think of another part of the Oxford English Dictionary (2019) definition:
“The arts and other manifestations of human intellectual achievement regarded collectively; The ideas, customs, and social behaviour of a particular people or society”
A comparative psychologist, like myself, might envisage something altogether more simple. For example, when I hear culture, I think of a family of chimpanzees sitting together cracking panda nuts in Taï Forest, Côte d’Ivoire. These different ways to perceive culture – and their contrast to the way I think of culture – frequently presents a problem for me when I am talking to people about culture in non-humans.
I often find myself hesitating to even use the term culture at all because, for some, it is synonymous with human culture, which is special – human culture is “cumulative” (Tomasello, Kruger, & Ratner, 1993). Whilst there are debates as to whether at least some non-human cultures also qualify as cumulative (see, for example, Schofield, McGrew, Takahashi, & Hirata, 2017), most would agree, human culture is special – even if that means that it simply often is cumulative (instead of always).
Therefore, my coauthors and I found ourselves seeking another term for the interesting processes that chimpanzees (and other non-humans) engage in regularly; in this post, I will be talking you through our logic in selecting a term and the pitfalls and advantages that the possible definitions contain.
In the nineties, there was a call for a distinction between cultures and traditions – the difference between these terms was a topic of significant debate (see Galef, 1992); Galef concluded that a tradition is a behaviour type that is somehow acquired, at least in part, by social learning mechanisms, other than imitation 1 or teaching. According to Galef, culture instead relies on imitation and teaching. Galef (and other early researchers e.g., Jane Goodall) should be applauded for their forward thinking “splitter” mentality – but, alas this distinction did not catch on as much as some may have preferred.
Somewhat expectedly, there is a degree of pushback within the field from what Galef termed “lumpers”, those who fail to see a distinction between cultures and traditions or may wish to attribute culture to non-humans. Culture, after all, has a nice ring and a high impact factor attached to it, and so, taking it away from many other animals has far-reaching consequences.
In a well-cited paper a group of field researchers from research sites across Africa sat down to compile their observations to generate a tentative list of the repertoire of wild chimpanzee behaviours; crucially, they divided up the repertoires by frequencies and by population (Whiten et al., 1999). This allowed them to produce a derived list from the behaviours themselves, namely a list of putative cultural traits of chimpanzees (see also Whiten et al., 2001). The logic being that population level (geographical) differences in behavioural repertoires might be due to cultural forces (this is similar logic to that employed in anthropology, for example, the different human cultures of eating food with hand, versus chopsticks versus cutlery etc). However, a factor missing from these reports (which was not identifiable with this so-called “method of exclusion”) was to pinpoint the exact underlying social learning mechanism(s). Indeed, even non-social learning mechanisms and that Galef would not even have counted as underlying traditions (let alone culture) often could not be excluded (Langergraber et al., 2011).
In using terms such as “culture” to describe these patterns of behaviour we, as a field, left these findings open to misinterpretation. In the original paper (Whiten et al., 1999, p. 685), it was directly claimed to be “difficult to see how such behaviour patterns could be perpetuated by social learning process simpler than imitation”, whilst useful, the data in this study do not allow the veracity of such a claim to be tested.
In examples like these, which are frequent, we can see how the current use of the term “culture” has become detached from that of Galef. Again: for Galef, for something to be called cultural it is required that the trait is indeed underlain by imitation. With this in mind, the evidence for chimpanzee imitation is all too often lacking; claims of imitation are usually misnomers or failures to control for variants of social learning other than imitation. Tests of ‘pure’ imitation (where a task cannot be solved by any social learning mechanisms other than one including action copying) reliably yield negative results (Clay & Tennie, 2017; Tennie, Call, & Tomasello, 2012; Tomasello et al., 1997). In other words, apes do not spontaneously ape (i.e., imitate). Hence, following the logic of Galef, the chimpanzee behavioural differences between populations are certainly interesting, but they are not cultural as they are not shown to be based on imitation – we would need to conclude that we have here evidence for chimpanzee traditions instead.
This debate has raged for some time, with adherents on both sides – and even we ourselves, one of the major objectors to ‘lumping’ are tired of it. But an alternative seems possible – and this is what we recently proposed (Neadle, Allritz, & Tennie, 2017). The solution is to simplify the definition of culture to the bone – we merely add qualifiers to the term, to not loose precision. That way, we hopefully can focus on collecting and comparing data rather than to waste resources fighting definitions.
We proposed the most minimal definition of culture that would seem possible. The bar for any animal to become cultural has been set intentionally low by our definition. This is so as not to alienate researchers from the start (if you like your animal species to have culture – while empirical evidence is still necessary even in our definition – the empirical test can be very easily made) and to allow the widest possible net to be thrown out to find animal culture. Arguably the latter is the best approach to enable us to detect general evolutionary patterns.
We, therefore, proposed the “minimal culture” definition: This definition directly equates the presence of any variant of social learning mechanism in any species with culture (Neadle et al., 2017). “Minimal” is simply part of the name of the definition and need not be added in front of the term culture. And so, if you find social learning of any flavour in your study species – congratulations, you have found culture. Crucially, our definition does not require that a specific social learning mechanism (such as imitation) is at play. In fact, a behaviour can be considered cultural – under this definition, if social learning is shown to have any influence at all. For example, if a social learning mechanism is at play that merely facilitates/catalyses the expression/frequency of a behaviour – that’s fine, and is, therefore, culture (compare also Tennie, Call, & Tomasello, 2009).
But with this new, low bar, we have not only rid the debate of the need to show imitation before one can talk of (minimal) culture (others have done the same in their own definitions for similar processes: e.g. Socially Mediated Learning; Caldwell & Whiten, 2002). Here, we took the lesson from the past – these fights about what is and isn’t cultural proved unnecessary bonfires of resources. And so, we designed our definition to really and truly be minimal – there is no additional baggage. In other words, social learning is culture. Thus, by using our definition, there is no need to argue whether, additionally, the behaviour itself is copied, whether it lasts so and so long, whether it appears in at least these many individuals etc.
It’s pure and simple and that’s why we like it. We hope you do, too.
Now, can we please use all our concentration on actual data, and stop fighting over words?
1 In this context, imitation is the copying of actions (Whiten et al., 2004), this is distinct from copying only the results of these actions – termed emulation. Yes reader, I know, term overload, but bear with me here! I am going to focus on imitation in this post – teaching is a whole new kettle of fish!
Caldwell, C. A., & Whiten, A. (2002). Evolutionary perspectives on imitation: Is a comparative psychology of social learning possible? Animal Cognition, 5(4), 193–208. https://doi.org/10.1007/s10071-002-0151-x
Clay, Z., & Tennie, C. (2017). Is Overimitation a Uniquely Human Phenomenon? Insights From Human Children as Compared to Bonobos. Child Development, 00(0), 1–10. https://doi.org/10.1111/cdev.12857
Galef, B. G. (1992). The Question of Animal Culture. Human Nature, 3(2), 157–178.
Langergraber, K. E., Boesch, C., Inoue, E., Inoue-Murayama, M., Mitani, J. C., Nishida, T., … Vigilant, L. (2011). Genetic and ‘cultural’ similarity in wild chimpanzees. Proceedings of the Royal Society B: Biological Sciences, 278, 408–416. https://doi.org/10.1098/rspb.2010.1112
Neadle, D., Allritz, M., & Tennie, C. (2017). Food cleaning in gorillas: Social learning is a possibility but not a necessity. PLoS ONE, 12(12), e0188866. https://doi.org/10.1371/journal.pone.0188866
Schofield, D. P., McGrew, W. C., Takahashi, A., & Hirata, S. (2017). Cumulative culture in nonhumans: overlooked findings from Japanese monkeys? Primates, (0123456789), 1–10. https://doi.org/10.1007/s10329-017-0642-7
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Tennie, C., Call, J., & Tomasello, M. (2012). Untrained Chimpanzees (Pan troglodytes schweinfurthii) fail to imitate novel actions. PLoS ONE, 7(8). https://doi.org/10.1371/journal.pone.0041548
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