When we think of culture, we tend to think about material products of human civilization and/or variation of traditions, rituals, and beliefs between different human populations. And of course, these are products of human culture. But does culture distinguish humans from all other animals? Are any other animals cultural? These questions have produced a “culture war” within academia that has deep implications for how we imagine what it means to be human.
Surprisingly, our contemporary understanding of culture is quite new. It was developed during the Enlightenment as a way for European intellectuals to describe differences in human behaviour throughout the world. The term wasn’t necessary in the same way during the pre-modern era because cultural diffusion was largely constrained by geography. As a result, very few people knew, or interacted with, people from vastly different cultural backgrounds.
Either way, throughout modern intellectual history, the term “culture” has been used as a defining characteristic of the human species. But is it? Are there behavioural patterns in animal communities that evolve and are transmitted in analogous ways to human societies?
Clues that we were not the only species to possess culture came from early studies of our closest relatives: chimpanzees. In the 1960s, primatologist Jane Goodall observed chimpanzees at Gombe Stream National Park making and using tools. At that time humans were defined as “man the tool maker.” After she told her mentor, paleoanthropologist Louis Leakey about her discovery, he famously replied:
Now we have to redefine man, redefine tool, or accept chimpanzee as human.
Of course, under any taxonomic classification scheme it would be foolish to redefine chimpanzees as humans, so we instead reclassified our species. We were no longer the only species that made and used tools, but did that also mean we were not the only species to possess culture?
As the top evolutionary scientists in the field pondered this question, it became evident that culture was a more complex term than had previously been thought. What was culture exactly? And if our closest relatives made tools, what else could they do?
Researchers without a clear grasp on what it meant to call a non-human cultural, started to refer to chimpanzee behaviour as “pre-cultural” or “proto-cultural.“ However, others were skeptical of this classification and believed they were observing cultural beings.
Here is an example of one such observation from the field notes of primatologist Christophe Boesch (1985):
Nova inserts her index finger in the soft soil and then sniffs it carefully. She starts removing slowly a layer of the soil so as not to alert the driver ants in their nest. She breaks a small branch of a sapling and cuts it with her teeth to produce a stick about 30 cm long. She starts dipping it quietly up to 2-3 cm into the nest entrance, watching as the ants climb up the tool. Once they have reached about 10 cm up the tool, she rapidly turns the end of the stick upwards into her mouth, hastily chewing the ants, and then dipping further.
Boesch was observing the practice of “ant fishing.” He knew that not all chimpanzee populations knew how to fish for ants. This was a population-specific behaviour. Afterwards, he wondered: how do such population specific behaviours appear? And do they represent chimpanzee cultures?
Primatological inquiry into these questions met resistance within anthropology. But evolutionary biologists were making equally perplexing discoveries in other species. Research on cetaceans like whales, dolphins, and porpoises, as well as birds like sparrows, starlings, and crows, revealed they possessed population-specific vocalizations and feeding behaviours that appeared to be socially transmitted.
These were thought-provoking results, but were these behaviours cultural? Using social transmission as the only criteria for culture allowed biologists like Charles Lumsden and Edward Wilson to conclude that more than 10,000 species, including some bacteria, could be deemed “cultural.”
The culture wars were just starting.
Cultural anthropologists were unconvinced by all these data and reasoning. They insisted that linguistic mediation was the key to achieving culture. They further argued that imitation of other members of a group couldn’t be correlated with culture.
Discussion of animal culture was becoming polarized, and evolutionary anthropologists were stuck in the middle. An understanding of the human condition was at stake.
In an attempt to break this stalemate, primatologists proposed a “nonarbitrary definition.” This definition sought to incorporate the importance of context; imitation alone was not enough. Also, in order to claim that a behaviour was cultural, researchers first needed to control for ecological and biological determinants of behavioural observations.
In order to apply these ideas to field research, primatologists developed the “method of exclusion.” By using this method, researchers would document behaviours between groups and then infer whether what they were observing was cultural by eliminating any possible ecological and/or genetic cause for its occurrence.
A big breakthrough in this research came in 1999, when several evolutionary scientists from six different long-term chimpanzee field sites compiled their behavioural data and attempted to determine how much cultural variation there was between chimpanzee populations in Africa.
Their results were startling. They found 39 different behavioural patterns, including tool usage, grooming and courtship behaviours that appeared to be unconnected to either ecological or biological determinants.
From: Cultures in chimpanzees
For example, chimpanzees at Budongo, Mahale, and Tai Forest performed rain dances. Chimpanzees at Gombe and Kibale had developed traditions for inspecting wounds and removing parasites (a form of self-medication now termed zoopharmacognosy). Other groups had different feeding traditions; in the west chimps frequently constructed anvils to break open nuts and constructed tools to fish for ants. In the east, they developed different tools to fish for termites. Their was also extreme variation in different social traditions and courtship rituals.
These results indicated that not only were chimpanzees cultural, but the complexity of their culture was without parallel throughout the rest of the animal kingdom. Research over the past decade has validated their results and increased our understanding of cultural variation within our closest relatives. For example, one group of western chimpanzees in Senegal constructs spears to hunt other primates. The ability to construct spears is taught, and context for the use of the spear is the difference between life and death.
Theorists that accept these discoveries as proof of culture in animals have now moved past the simple cultural dichotomy erected during the culture wars. If chimpanzees and other animals possess complex culture, what makes us so different?
Although research into the question of cultural complexity is still in its infancy, some researchers believe that the key is the cultural “ratchet effect.” Human culture appears to be characterized by a generational increase in complexity and/or efficiency. There is little evidence that any other animals have ratcheting culture.
Of course, we have been wrong before. If scientists had a chance to study Australopithecus africanus or Homo erectus they might have concluded that those species had no ratcheting culture just because of how slow and gradual complexity evolved in their technologies and traditions. For example, Homo erectus tool technology remained remarkably stagnant over a period of one million years. Therefore, future research on generational transmission of culture within and between groups may reveal new insights. Also, there are many chimpanzee populations that have never been studied, and research on other great apes like gorillas, bonobos, and orangutans, has only just begun. As is typical of scientific inquiry, one answer, usually leads to even more interesting and perplexing questions.
The understanding of what culture is, and what separates human culture from animal culture, is one of the most important aspects of our quest to understand the human condition. Exploring these questions is the point of The Ratchet.