In an interesting new paper, Krist Vaelsen and Wybo Houkes (V&H) ask if human culture is characteristically cumulative or not, and more particularly, whether there is evidence for this. A variety of authors, many well-known names, respond:
Is Human Culture Cumulative?
The question might sound like a no-brainer. Surely the evidence of cumulativeness is all around us? Well, yes, but V&H are setting the bar higher. They are asking if cumulativeness is a characteristic of human culture, rather than just an occasional occurrence. This is a good question: for a lot of our history (the longest part, measured in hundreds of thousands of years) stone tool sets did not accumulate innovations. Some of these tools (both flaked and polished stone tools) were still in use in Australasia and the Pacific region in recent times, like the one at the top of this post. They apparently served their makers well.
I will not attempt to summarize all the arguments and counter-arguments, rather I make one general observation about the entire discussion. The naive scholar might get the impression that human culture is (in the first instance) a philosophical topic. The discussion is mainly couched in generalities (both the original paper and the responses). Authors take ‘positions’ on various point of view. There are pleas for more ‘real world datasets’ but little detailed discussion of actual datasets that could answer the questions raised by V&H (Ceri Shipton’s excellent evidence-based discussion of hunter-gatherer toolkits stands out as the exception). The facts discussed are mainly of the ‘stylized’ variety (to use Richerson and Boyd’s expression).
V&H’s excellent questions can be answered to a large extent. Detailed, non-WEIRD studies of human cultural change over a large scale and long time period, spanning the range from simple to complex (the latter characteristic being objectively measurable) do exist. For example:
The Evolution of an Ancient Technology
What are the conclusions? Simply put, V&H are right in one of their key points. Human culture is sometimes cumulative, but not always. Some simple technologies have survived virtually unchanged since Neolithic times (or earlier). Some lineages did accumulate complexity, with demonstrable continuity with the earliest forms. Some lineages even lost complexity. This aspect is driven by other factors (societal, economic), it is not an intrinsic property of cultural change.
Cultural change is a complex empirical question, that can only be answered satisfactorily with high quality data. The kind that takes years of fieldwork and years of coding work to accumulate.
Larena et al’s recent paper “Multiple Migrations to the Philippines during the last 50,000 years”  reveals the genetic signatures of at least five waves of migration to the islands. Rather than a single colonization event around 4000 years ago, suggested by the well-known ‘Out of Taiwan’ model, several different groups appear to have journeyed to the northern Philippines between around 15,000 and 8,000 years ago. These migrations pre-date the arrival of agriculture and were presumably coastal-dwelling foragers, who left their genetic signatures in Cordilleran peoples in the north of the islands.
The Philippines archipelago is an important staging post for the expansion of the people who are now called Austronesians, who inhabit large parts of the Indonesian and Philippines islands, alongside Austro-Papuan migrants who arrived earlier. In recent years understanding of this migration has been dominated by the ‘Out of Taiwan’ model, which posits that the first representatives of this group journeyed from the southern tip of Taiwan to the northern coast of the Philippines around 4000 years ago, before continuing their migration south and east into other parts of ISEA. Larena et al’s findings don’t mean that the ‘Out of Taiwan’ model of Austronesian expansion is completely wrong, but rather that this particular migration was one amongst many. This shouldn’t come as a surprise. Many elements of present-day Austronesian life, such as the pigs, dogs and chickens that are an integral part of village life, have been shown to have originated directly from the Asian mainland.
When I investigated weaving techniques and looms a decade ago, it became clear that these techniques were known to the earliest migrants speaking Malayo-Polynesian (MP) languages, but could not have come from Taiwan . Weaving is deeply embedded in Austronesian culture, made clear by the work of Robert Blust and others, who found cognates for weaving tools and practices in far flung locations across the archipelago. Blust’s reconstruction of proto-Malayo-Polynesian includes a core vocabulary for weaving and textiles, including the verb ‘to weave’ (tenun), terms for the weaver’s sword-beater (balira, baliga, balira), cloth beam (atip, ati, apit, hapit) and a tubeskirt (tapis, tais), amongst others. However, the Malayo-Polynesian loom is different from the one found today amongst aboriginal peoples speaking Austronesian languages on Taiwan. It incorporates an improved warp beam fixing method that is found today in mainland Southeast Asia (MSEA) and the foothills of the Himalayas, mainly amongst Austroasiatic and Tibeto-Burman speakers. Characteristic Malayo-Polynesian techniques such as warp ikat and making tubeskirts are also absent in Taiwan but common in MSEA:
Photos: an Ifugao weaver from the Cordilleras (left) uses a typical Malayo-Polynesian loom with a warp beam (furthest from the weaver) fixed to an external point. She can weave a long and wide cloth on this loom. A Kavalan weaver from Taiwan (right) uses a simpler loom with the warp beam lodged behind her feet. This kind of loom is less versatile, and best suited to shorter, narrower pieces of cloth.
The most likely scenario is that migrants from Taiwan arriving in northern Philippines were joined by migrants arriving directly from the Asian mainland, perhaps from several locations, over a period of several thousand years. Some aspects of mainland culture, such as weaving techniques, proved more convenient than the versions from Taiwan, so it was the mainland versions that spread throughout the archipelago.
With hindsight, it was never particularly plausible that all Austronesian migrants came from Taiwan. The Taiwan-Phils sea crossing is a tricky one (if your navigation is not up to scratch you are liable to find yourself in the middle of the Pacific). If seafaring vessels and navigational skills were up to the mainland-Taiwan and Taiwan-Phils crossings, there must surely have been many other easier routes that were regularly navigated at that time.
Furthermore, there are no MP languages spoken on Taiwan today, except by the inhabitants of Orchid Island in the far south, who seem to have arrived at their present position relatively recently (they speak a Bashiic language, related to those of the Philippines, and use the Malayo-Polynesian loom, and their material culture is distinctly different from groups living on Taiwan). The Austronesian languages spoken on Taiwan are related to MP, but belong to different branches of the ‘tree’. So, wherever proto-MP originated, it was probably not on Taiwan.
This being the case, why does the ‘Out of Taiwan’ model exercise such a powerful hold on collective thinking about Austronesian migrations? It is a ‘good story’ of course, but there are four other reasons that I can think of:
1) Historical accident – the loss of mainland evidence
The Asian mainland, in the region of the Yangtse valley and what is now Southern China, was once an ethnically diverse region, probably with diversity that rivalled or exceeded MSEA today. This included the ancestors of Tai-Kadai, Austronesian and Austroasiatic groups. Nearly all of this diversity disappeared within the last 2000 years as a result of the expansion of Han speakers. The descendants of groups who sailed to Taiwan are now completely gone. As a result, Taiwan is now the remaining pocket of deep-time diversity of Austronesian peoples. Inevitably, linguistic and genetic reconstructions point to Taiwan, because they can point nowhere else. This is not evidence for exclusive Taiwan origins, but an artifact created by the loss of mainland evidence.
2) Tectonic circumstances – difficulty of coastal archaeology outside of Taiwan
Many of the earliest settlers lived on the coast. But coastal archaeology in ISEA is difficult: key sites are submerged by rising sea levels in the last 10,000 years. In contrast, archaeologists on Taiwan are fortunate. Aside from relatively good funding for their investigations and a long history of archaeological work, they live on an island which is being uplifted at a remarkable rate – between 0.5cm and 1cm a year on many parts of the coast. This means that early coastal settlements are well-documented, whereas in most parts of ISEA archaeological finds are mainly in caves … transient-occupation sites that offer few clues about populations and lifeways.
3) Signal strength
Archaeological work is hard, but the ‘signal’ from the early agricultural Neolithic is amongst the easiest to spot, because intensification of land use supported larger populations, who left distinctive stone and pottery tools. The ‘signal’ from early settlers from Taiwan … shouldered adzes, red-slipped pottery … is traceable across ISEA, whereas other groups (such as coastal foragers) are harder to spot.
4) Expansionary languages: winner takes all
There are a number of examples of expansionary language groups (Indo-European, Bantu, Austronesian) that have come to dominate large geographical areas. This tendency can give the impression that such expansions were monolithic in character. The genetic evidence tells a different and more complex story.
To re-iterate: none of this means that the detailed archaeological work tracing the movements of Neolithic peoples from Taiwan to the Philippines is wrong. That population movement is real. But, as Larena et al have shown, it isn’t the only one.
1. Multiple migrations to the Philippines during the last 50,000 years. Larena et al
Proceedings of the National Academy of Sciences Mar 2021, 118 (13) e2026132118; DOI: 10.1073/pnas.2026132118
2. Buckley, Christopher. "Looms, weaving and the Austronesian expansion." In: Spirits and Ships: Cultural Transfers in Early Monsoon Asia. Singapore: ISEAS Publishing (2017).
Cultural Evolution and its Discontents: Cognitive Overload, Parasitic Cultures and the Humanistic Cure, by Robert N Watson. Routledge, 2019.
Robert Watson is the Distinguished Professor of English at UCLA. Before opening his book, I wondered what an English professor make of the topic of cultural evolution. I confess that I expected something negative in tone, something critical of the intrusion of science-y ideas into the field of human culture.
Far from it. Watson takes the idea that culture evolves as his starting point, embraces it, and runs with it. In this book he explores some of the consequences of this idea for understanding the role of humanities in society, and for education in particular.
In some ways this book picks up where Joseph Henrich’s book ‘The Secret of Our Success’ ends. Though I don’t think that Watson intended his book as a direct response to Henrich’s book, nevertheless there is continuity in key themes. Henrich’s work takes the long view of humanity’s progress, and is infused with sunny optimism about how well we have done. On the final page of his book he says:
‘we should take a page from cultural evolution’s playbook and design “variation and selection systems” that will allow alternative institutions or organizational forms to compete. We can dump the losers, keep the winners, and hopefully gain some general insights during the process.” (Henrich, 2019, p331).
Watson’s view, which is focused on the predicament we find ourselves in in the early twenty-first century, and even more specifically in the United States of America, is rather less sunny and optimistic.
He begins his book by reviewing the notion of ‘culture’, which he sees as a ‘mutually reinforcing system of ideas, rules, values and practices adopted by a community – and there can be many overlapping cultures and communities’ (p24). Culture is characterized by transmission, variation and selection, and Watson points out that these are necessary and sufficient conditions for evolution of a Darwinian kind to take place. As he also points out, the ‘absence of the genetic functions of biological evolution’ are no barrier to this.
In the first three chapters of his book, Watson presents a sophisticated discussion of the role of culture, which he views as (in part) an information processing system, that allows us to make sense of vast amounts of data and social interactions of our daily lives, and to tame the ‘cognitive overload’ that might otherwise result. Culture does this by providing pre-learned, socially acceptable responses to frequently-encountered as well as novel situations. Some of Watson’s discussion blurs the boundary between evolved cognitive mechanisms that are biologically inherited, and cultural mechanisms that are learned, but this does little to diminish his argument. Culture as a system for processing cognitive inputs, especially those of a complex and higher order, is a nice description.
Watson’s understanding of cultural evolution is subtle and insightful, which begs the question of why so many scholars in the humanities struggle with the notion, believing it to be a kind of evil and pernicious reductionism. The answer might lie partly in Watson’s background in the study of language: linguists realized that the world’s languages evolve long before Darwin thought of applying the same notion to biology (1). But I think the most important factor is his ability to simultaneously comprehend processes operating at a variety of scales, from the individual to the societal, and to appreciate that what looks like one thing at a micro scale may look quite different when viewed on progressively larger scales. The difficulty of simultaneously appreciating processes operating at different scales is equally challenging for scholars of the sciences and humanities (interminable arguments over ‘free will’ are proof of this).
The aspect that interests Watson is the recognition that an evolving cultural system (which he calls a ‘memeplex’) takes on a life of its own, creating its own niche and ensuring its own replication and continuation. Some aspects of these systems may be neutral or maladaptive … even ‘parasitic’ … rather than beneficial for their hosts. By maladaptive behaviours Watson means ‘population-level evolutionary trade-offs’ that arise because ‘the costs of inventing and testing new behaviors outweigh the benefits of merely imitating the established behaviors’ (p68), citing work by Richerson and Boyd.
Watson is correct (it seems to me) in identifying that some aspects of culture may be maladaptive, but I would have liked a fuller discussion on what maladaptive means and how such aspects can be identified (this is not a trivial task). Some aspects of culture that Watson discusses, such as opioid addiction, are clearly maladaptive. Others, such as political ideologies that the author singles out, less so. Both Robert Watson and I dislike extreme political ideologies intensely. But are these ideologies maladaptive? It’s a good question, and one that I don’t have an answer to (2).
Where Watson’s argument succeeds is in reframing the oppressive and dehumanizing systems that our culture has given rise to, for which he uses various shorthand designations such as neoliberalism (3), as harmful ‘memeplexes’. These systems are viewed as conspiracies within contemporary, left-leaning criticism. Watson demonstrates that they are not … there is no villain pulling strings at the centre, rather there are runaway set of ideas that have taken on lives of their own.
Watson’s solution to this issue, which he devotes the remaining chapters of the book to, relates to the ‘variation’ part of evolving systems. He sees the role of the humanities, and in particular the role of the creative artist as providing an important part of the ‘variation’. He argues that the arts and literature provide a kind of sandpit in which novel ideas and ways of living can be kicked around, other roads travelled and other lives lived in fictional form. He realizes that this is (coming from an English professor) to some degree self-serving, but he makes an eloquent and convincing case for its truth. The degree to which quotes, memes and sayings of revered individuals, whether real or ‘fake’, are part of our daily experience of culture suggest that he is on to something.
Watson is (as you would expect) critical of the current trend towards focusing education exclusively on utilitarian, career-oriented outcomes, monetized and tracked in dollar-equivalent terms. He is equally dismayed by the shrinking space for discourse in modern universities, in which students and teachers are monitored for microaggressions. He sees the arts, and his field of literature in particular, as providing the opposite, a safe zone in which novel ideas (including ones that are dangerous to the status quo) can be formulated and their consequences explored. He goes so far as to compare literary studies to ‘Purgatory, that prepares us to leave … Hell for a better place’ (p176). The simile seems apt to me, though perhaps a little too bold for next year’s course prospectus.
This is a thought-provoking book, that takes contemporary notions about how cultures evolve, and explores their implications for literature and the humanities. Watson makes an eloquent and convincing case that extricating ourselves from our current predicament requires us to train the next generation in more than just physics and economics.
1. Van Wyhe J. The descent of words: evolutionary thinking 1780–1880. Endeavour. 2005 Sep 1;29(3):94-100.
2. The question is addressed in a graphic way in Paul Verhoeven’s film adaptation of Heinlein’s novel ‘Starship Troopers’, in which an unpleasantly militaristic society triumphs over equally murderous aliens.
3. The author provides a definition of neoliberalism as ‘a kind of mutual defense treaty between capitalism and a plutocratic version of government …’ which seems to me to be an accurate description of the appalling fix we find ourselves in right now … except that there is nothing ‘neo’ about it and very little that is ‘liberal’. I suggest ‘Palaeocapitalism’ as an alternative.
“The naming of cats is a difficult matter
It isn't just one of your holiday games
You may think at first I'm mad as a hatter
When I tell you a cat must have three different names.”
T S Elliot, 1939.
In the past decade I’ve been an enthusiastic user of evolutionary models and methods to examine culture. So why do I call myself by the long-winded title "researcher in ..." rather than “Cultural Evolutionist”? After all, a fair number of people seem to be adopting this label. And many biologists seem happy with the term “Evolutionary Biologist”. So why not join the trend?
There are three reasons.
Firstly, all biological organisms most definitely Evolve, which makes “Evolutionary Biologist” pretty uncontroversial. But culture is a mixed bag. Some things evolve in a Darwinian kind of way (eg core language lexicons and some material culture traditions), and some things don’t. Calling oneself a “Cultural Evolutionist” therefore seems to be jumping the gun just a little. Some aspects of culture can be better modelled with an epidemiological approach (eg slang … how and when did “basic” become a term of abuse??) but I am not aware of anyone calling themselves a “Cultural Epidemiologist”.
What there is, is people who study culture in a systematic way. Good.
Complex systems, like culture, exhibit a variety of emergent behaviours. These cannot be modelled from first principles, eg by solving the Schrödinger Equation. But they can be tackled with a variety of approximate models and systematic approaches, which can reveal a great deal about what is going on. The trick is knowing which of these tools to pull out of the bag. Evolutionary models are one group of tools. They are not the only ones. In the study of material culture (for example) I have found that plotting stuff on a map can be as revealing as a full-blown phylogenetic study. It’s important to have a bag of tools that bulges with more options than just evolutionary models.
The second reason relates to the history of Cultural Anthropology over the last 150 years. A lot of past work has not met the basic minimum standard to be called “science”, and the field has been subject to fads and fashions. Seen in the rear-view mirror, much of 20th century cultural anthropology is starting to look like a Rorsach Blot, a mess onto which anthropologists projected their fears and fantasies.
In contrast, in the last 3 decades there has been an encouraging growth in systematic approaches that seem to be bearing fruit. “Cultural Evolution” is currently a hot area, and some are tempted to adopt the label. There’s also funding out there to be had. The risk is that this is viewed by those outside the field as another “turn” in anthropology. Such things are customarily debated on aesthetic and political grounds, rather than with evidence. Cultural Evolutionary studies already face push-back along these lines (I have been on the receiving end myself). This is exacerbated if we call ourselves “Cultural Evolutionists” since this label makes it sound as if we have nailed our colours to a particular mast. We might argue that “evolution” (with a small “e”) simply means “change over time”, but most outside the field will assume that we are talking about Evolution of the Darwinian kind. And sometimes we will be. But not always.
By the way, I can completely forgive anyone who studies culture in a systematic way not wishing to call themselves an “Anthropologist”. No-one likes to be associated with failure.
The third reason relates to the trend towards increasing sub-division and specialization in academia. Sub-fields, once defined, tend to operate like guilds: The Worshipful Company of Whateverists. If you have worked in an academic field you will have encountered these guilds, with their holy books, hierarchies, apprentices, and high priests. This is a great approach for advancing the interests of stonemasons and silversmiths, but it is problematic for science.
I hanker after the 19th century, when researchers were mostly called “scientists” or “naturalists”. Even when I was growing up there were still “naturalists” around. I suppose this is nostalgia, and completely unrealistic. But I’m still drawn to the idea that the most interesting thinkers (in any age) resist characterization.