Category Archives: Evolution

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Issues in Cultural Evolution 2.2: ‘Cultural Genes’ are Out There in the World

I think the thing to do at this point is post a version of my own view of cultural evolution, but one that skips the terminology that I’ve recently adopted. In this version, which more or less centers on my 1996 article, Culture as an Evolutionary Arena, I adopt the term “meme” as the name of the genetic entities of culture. Though I’ve recently dropped the term, I’ll use it in this post.

Gavagai and Conduits

First, though, I want to think a bit about the problem of evolving a communication system.

Some years ago I was engaged in an email conversation with Valerius Geist, a naturalist, who pointed out that biological communication systems are very conservative because they have to evolve two sets of matched traits. They’ve got to evolve a system to emit signals – vocal calls, gestures, postures – and one that understands those signals. These two systems have to match. If they don’t, the communication will fail.

Culture has the same problem, which we can illustrate with a classic thought experiment in the philosophy of language. This is from Willard van Orman Quine, Word and Object (1960). He asks us to consider the problem of radical translation, “translation of the language of a hitherto untouched people” (Quine 1960, 25). Consider a “linguist who, unaided by an interpreter, is out to penetrate and translate a language hitherto unknown. All the objective data he has to go on are the forces that he sees impinging on the native’s surfaces and the observable behavior, focal and otherwise, of the native.” That is to say, he has no direct access to what is going on inside the native’s head, but utterances are available to him. Quine then asks us to imagine that “a rabbit scurries by, the native says ‘Gavagai’, and the linguist notes down the sentence ‘Rabbit’ (of ‘Lo, a rabbit’) as tentative translation, subject to testing in further cases” (p. 25).

Quine goes on to argue that, in thus proposing that initial translation, the linguist is making illegitimate assumptions. He begins his argument by nothing that the native might, in fact, mean “white” or “animal” and later on offers more exotic possibilities, the sort of things only a philosopher would think of–one of the possibilities was “mere stages, or brief temporal segments, of rabbits” (p. 46). Quine also notes that whatever gestures and utterances the native offers as the linguist attempts to clarify and verify will be subject to the same problem. Quine’s argument is thorough and convincing.

This situation, of course, is rather different from that of ordinary speech between people who share a common language. In the common situation both parties would know the meaning of “Gavagai.” Yet, however effective it is, ordinary speech sometimes fails to secure understanding between people and, when such understanding is achieved, that achievement has required back-and-forth speech. The mutual understanding is achieved through a process of negotiation. As William Croft reiterates in chapter 4 of Explaining Language Change, we cannot get inside one another’s heads and so must negotiate meanings in conversation.

That is to say, communication through language is not a matter of sending information through a pipeline. It does not happen according to what Michael Reddy (1993 in Ortony, Metaphor and Thought) has called the conduit metaphor. Reddy’s article is based on 53 example sentences. Here are the first three (p. 166, italics in the original):

1. Try to get your thoughts across better
2. None of Mary’s feelings came through to me with any clarity
3. You still haven’t given me any idea of what you mean

Reddy’s argument is that many of our statements about communication seemed to be based on the notion of sending something (the thought, idea, feeling) through a conduit, hence he calls it the conduit metaphor. He knows that communication doesn’t work that way, but that’s not his central issue. His central concern is to detail the way we use the conduit metaphor to structure our thinking about communication.

Of course, language is not the only medium of human communication and culture. One can craft a wheel that’s just like an existing wheel without having to know what the wheelwright was thinking. As long as your wheel is acceptably like existing wheels, it is OK. How you made it is secondary. Even there, of course, you can observe a master wheelwright at work and imitate his process. One can learn music through imitation as well.

That is, as long as there is a publicly visible physical model, of an object or a process, one can learn how to make the object or perform the process through imitation, hence the emphasis on imitation in the memetics literature. Imitation fails, however, when it comes to the meanings of words. You can learn to imitate sounds, but not meanings. The learning of meaning is different, and it is something that’s been all but ignored in the orthodox memetic literature. That literature assumes that we “transfer information” like sending oil or water through a pipeline. It uses a reified concept of information to dissolve the problem, rather than solve it. It is not well-informed about cognitive science and linguistics and so cannot be considered intellectually serious. Continue reading

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Rhythm Changes: Notes on Some Genetic Elements in Musical Culture

That’s the title of another working paper. You may download it from Academia.edu (HERE) or from Social Science Research Network (HERE).

Here’s the abstract:

An entity known as Rhythm Changes is analyzed as a genetic entity in musical culture. Because it functions to coordinate the activities of musicians who are playing together it can be called a coordinator. It is a complex coordinator in that it is organized on five or six levels, each of which contains coordinators that function in other musical contexts. Musicians do not acquire (that is, learn) such a coordinator through “transfer” from one brain to another. Rather, they learn to construct it from publically available performance materials. This particular entity is derived from George Gershwin’s tune “I Got Rhythm” and is the harmonic trajectory of that tune. But it only attained independent musical status after about two decades of performances. Being a coordinator is thus not intrinsic to the entity itself, but is rather a function of how it comes to be used in the musical system. Recent argument suggests that biological genes are like this as well.

Here’s a key sequence of paragraphs:

In the case of music, let me suggest how different musicians understand Rhythm Changes is irrelevant as long as they can stay together while performing together. Charlie Parker’s neural patterns for Rhythm Changes may have been different from Dizzy Gillespie’s or Miles Davis’s or Thelonious Monk’s, but that doesn’t matter as long as they’re together on the bandstand. That is something they can judge perfectly well in performance, as can listeners. The question of how accurately patterns are “transferred” from one brain to another is mistaken.

I’ll go so far as to say that even when a neophyte is learning from a master, there is no transfer of patterns from the master’s brain to the neophyte’s. Rather, as they play together, the neophyte responds to what the master is doing and figures out, in his own (neural) terms, how to match or complement, as the case may be, what the master is playing. The student will make mistakes, the master will make comments, and they’ll try again.

There is no transfer of patterns in the sense that computers can transfer information from one machine to another. We have learning from public models, and we have interplay, negotiation, and mutual adjustment. How individual musicians achieve these results, what goes on in their brains, is a secondary matter. Whatever it is, it isn’t a matter or either sending or receiving information.

The introduction finishes out this post. Continue reading

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Issues in Cultural Evolution 1: Cultural Stability in the Mesh

This is the first of a series of three posts – I hope it’s only three – in which I explore the relationships between my views on cultural evolution and the views of more orthodox thinkers. The number of thinkers is in fact quite large, but I don’t intended to be exhaustive, just indicative. For the most part I’ll be working with reference to two sources:

1.) Alex Mesoudi, Cultural Evolution: How Darwinian Theory Can Explain Human Culture & Synthesize the Social Sciences, Chicago: 2011.

2.) An online report of a workshop that Daniel Dennett convened at the Santa Fe Institute that included the following evolutionary thinkers: Susan Blackmore, Robert Boyd, Nicolas Claidière, Peter Godfrey-Smith, Joseph Henrich, Olivier Morin, Peter Richerson, Dan Sperber, Kim Sterelny. Note that while most of these thinkers have special interests in cultural evolution, two of them are more generally interested in evolution, Godfrey-Smith and Sterelny.

In this first post I’m concerned with a general framework in which to think about culture and its evolution. In the second post I’ll examine the micro-scale mechanisms of cultural evolution, the cultural analogues to the biological gene and phenotype. In the third post I’ll look at the large-scale dynamics of cultural evolution. And, who knows, maybe there will be a fourth post to put things together. We’ll see.

Stability in the Mesh

Let me start out with a standard distinction, between culture and society. A society is a group of people and culture is the attitudes, ideas, customs, and practices through which they interact. Thus I will not be using the term “culture” to refer to a society, a common usage.

In the simplest societies people lived in relatively small bands of hunter-gatherers and had relatively few material possessions. Whatever they possessed they had to carry with them from one place to another. Everyone knew everyone else and they were, as well, acquainted with those living in neighboring bands. Those people were, after all, their friends and relatives.

When I talk of the mesh I mean those people and their relationships among one another, among and with their material goods, and with the features and creatures of their environment. That is where human culture arose, in that mesh. Culture provides a means of enriching those relationships, both by introducing new entities into the mesh – whether handcrafted objects, new activities, or various abstract entities, and so forth – and by establishing new kinds of relationships among entities in the mesh.

It is only to the extent that these entities and relationships are stable that the group can be said to have a coherent culture. Dawkins makes that point with respect to biology in the second chapter of The Selfish Gene (p. 12):

Darwin’s ‘survival of the fittest’ is really a special case of a more general law of survival of the stable. The universe is populated by stable things. A stable thing is a collection of atoms that is permanent enough or common enough to deserve a name. It may be a unique collection of atoms, such as the Matterhorn, that lasts long enough to be worth naming. Or it may be a class of entities, such as rain drops, that come into existence at a sufficiently high rate to deserve a collective name, even if any one of them is short-lived. The things that we see around us, and which we think of as needing explanation–rocks, galaxies, ocean waves–are all, to a greater or lesser extent, stable patterns of atoms. Soap bubbles tend to be spherical because this is a stable configuration for thin films filled with gas. In a spacecraft, water is spherical globules, but on earth, where there is gravity, the stable surface for standing water is flat and horizontal. Salt crystals tend to be cubes because this is a stable way of packing sodium and chloride atoms together. In the sun the simplest atoms of all, hydrogen atoms, are fusing to form helium atoms, because in the conditions that prevail there the helium configuration is more stable. Other even more complex atoms are being formed in stars all over the universe, and were formed in the ‘big bang’ which, according to prevailing theory, initiated the universe. This is originally where the elements on our world came from.

Dawkins then goes on to argue that stability in the biological world depends on molecules he will call replicators (p. 15). At first these replicators were free-floaters in the primeval biomolecular soup. In time they became (p. 20) “genes, and we are their survival machines.” I understand that there is some controversy within biology as to whether or not Dawkinsian replicators are in fact the source of stability in the biosphere (see Peter Godfrey-Smith, The Replicator in Retrospect, Biology and Philosophy 15 (2000): 403-423), but that is secondary to my current purpose.

What’s important is Dawkins’s plea for stability as the necessary precursor to meaningful change. That is as important in culture as in biology. Without stability there is no chance of accumulation cultural innovations.

With this in mind, let’s go back in time. Here’s a passage from my review of Steven Mithen’s book on music (“Synch, Song, and Society”, Human Nature Review 5, 2005, pp. 66-85):

Obviously we have no record of these utterances, but the archeological record does have indications of cultural conservatism. The repertoire of stone tools was both limited and unchanged between 1.8 and 0.25 million years ago; Mithen gives particular emphasis to the constant form of hand-axes (164). Mithen suggests that, because their finely wrought form exceeds the practical demands of butchery, wood-working, and cutting plants, these hand-axes may have been fitness indicators in the sort of sexual selection regime Geoffrey Miller has advocated.

Beyond this, I note that Ralph Holloway (1969, 1981) long ago suggested that strongly conserved hand-axe form was an indicator of social norms. Those forms could not be conserved from one generation to the next unless there was a deliberate intention to do so. One has to note the significant features of an existing axe and discipline one’s knapping motions to produce that result. That is considerably more exacting than simply producing an axe with a sharp edge and appropriate heft. The motivation behind such exacting form, then, is not practical. Nor can it be merely aesthetic, which would allow for considerable individual variation. That leaves us with a desire to conform to social norms. Given the importance of such norms, that may in itself be a sufficient motivation for their form, to serve as a visible token of social solidarity. In any event, Holloway’s observation does not contradict Miller’s, and now Mithen’s hypothesis. Norms are norms, regardless of their specific purpose and norms that serve multiple ends are likely to be particularly strong.

My point is a simple one: the oldest evidence we have of specifically human cultural norms is of something that can be seen and therefor copied, those stone axes. Of course, we know little of the lifeways that those creatures lived. The oldest, of course, were not human. Since we cannot observe them we do not know exactly how they made those axes, but archaeologists have experimented and so we know something of the likely techniques.

Whatever those techniques were, exactly, those no particular mystery about how they were passed on from one person to another as the crafting would have been fully observable. As they saying goes, hominid, hominid do. What we don’t know is just what neuro-motor advances made this activity possible, nor why they did it. What we see in the fossil record, however, is stability, norms. That’s what we need to get started. Continue reading

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Cultural Beings Evolving in the Mesh

This one wrestled me hard. In it I use new terminology and concepts–coordinators, phantasms, cultural beings–as though I know what they mean and am comfortable with them. But that’s not quite the case. It’s only recently that I’ve invented them. It’s one them to use terms in a document where you define them. It’s another thing to use them in an extended exposition. That’s where they come to define themselves. So this post, a long one, is something of a shake-down cruise. Sure, I’d like to have things all worked out nice and neat. But there’s no way to do that except to put the terms out there and see how they do. That’s what I’m doing.

* * * * *

In this post I further explore the notion of a cultural being and I introduce a metaphor for culture, that of a hyperfluid (cf. Tim Morton’s concept of a hyperobject). A cultural being, if you recall, consists of an envelope or package or coordinators along with all the actions that have given it life. It is thus a rather strange notion, which is why I want to explore it.

And I want to explore it in tandem with another strange notion, that of culture as something we might call a hyperfluid, something that has multiple levels of viscosity and thus changes at different rates. I’ve long thought of the brain, as a functioning entity, as hyperfluid in this sense. At the deepest “thickest” layer we have the physical structure of the brain itself. At the most superficial “thinnest” layer we have the flickering of neural impulses from one millisecond to the next. But that flickering can lead to changes in synaptic structure and, over time, those changes can “rewire” the brain at a fairly “deep” level, so-called cortical plasticity.

So it is with culture, which is, after all, a collective product of the brains of all those individuals in a social group over the life of the group. The thickest cultural layers settle to the bottom. These are the features that endure over decades and centuries, if not millennia. It’s at culture’s thin surface that we see ordinary everyday behavior. Here is where people read books, and write them, where they listen to music, and make it. In this process each individual will participate in many cultural beings and will, in turn, be shaped by them. And some cultural beings will attract only a few individuals while others will attract more. Some of those cultural beings will outlive any and all of the individuals that have participated in them.

What we have, then, are collections of individual human beings, biological beings, on the one hand. Each of them participates in and is (partially) formed by many cultural beings. On the other hand, we a bunch of collection of cultural beings, each of which has attracted participation by at least some individual humans while some will attract participation by many humans. Some of the latter are able to attract participation over decades and even longer, so that they outlive any of the humans that have participated in them. It is the interaction of these two sets of beings that give us this hyperfluid culture that lives in the social mesh.

Notice that I talk of cultural beings as living. They are and they are not. Coordinators–targets, couplers, and designators–are not alive. The humans who read the books and listen to the music, of course, are alive and it is that vivacity, their phantasms, which I am, in effect, allocating to the books and musical performers they witness. Cultural beings as I have defined them do change. While they are utterly dependent on humans, they also have a degree of autonomy from any individual humans. They are neither alive nor inanimate in a strict sense. So I will refer to them as being alive, a provocation that seems warranted as a device to stimulate thought.

Being in the Mesh

What do I mean by the mesh? For the most part I’m using that term as more or less equivalent to what Latour has in mind when he talks of networks of social actors, where the actors are not just humans, but everything encompassed within society, the humans, animals, plants, and material objects, both natural and man-made. All of it is gathered into the causal nexus of the social: the mesh.

But let’s start with the humans, biological beings. Make no mistake, they’re the ones that hold the mesh together, and culture is the glue that they deploy. So far as we know, the most basic case is that of foraging bands of hunter-gatherers. That’s how humankind began on the African savannas. Let’s think about them for just a bit to refresh ourselves.

Such bands typically have a dozen to thirty or forty members, all of whom know one another, some better than others, but all of them face-to-face relations. A number of bands will occupy a given territory, and people in any given band will have friends and relatives in other bands. So maybe we have two hundred or a thousand or more people all speaking more or less the same language and having more or less the same culture.

Those people and their relations are the core of the mesh. But we must also include the environment in which they live and the artifacts they’ve manufactured. They too are part of the mesh. They mediate relations among the humans.

Those non-humans are ‘covered’ with coordinators through which the humans assimilate them into their cultural system. Humans often place markings in the environment, such as slash marks on trees, or paintings on rock faces of cliffs and in caves. Or they may place stones to mark boundaries, and so forth. But environmental features often enter into myths and stories without themselves being physically altered and so become assimilated to culture. All of these involve coordinators in the technical sense I’ve been using.

Those myths and stories are what I have come to call cultural beings, as you recall from the introduction, a term I use to encompass not only the string of linguistic signifiers used to convey the stories, that is, the envelopes of coordinators, but the various individual mental acts (the phantasms) giving them life. Some or many of those environmental features may also function as cultural beings if they figure centrally enough in mythology and in the group’s way of life, that is, if appropriate phantasms are consistently associated with them. But I don’t want to get into figuring out just what qualifies as a cultural being. The question is an important one, but I’m going to leave it for later. For my immediate purposes we can regard the term as something of a placeholder whose extension will be in a specified later more specialized discourse. We can make do with some rough and ready observations. Continue reading

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What is Culture that it can Evolve? The Mesh, from Individuals to the Group

Things are complicated, and there’s a sense in which I’ve jumped the gun in some of my earlier posts in this current series, which I’ve provisionally titled “Cultural Evolution: Literary History, Popular Music, Ontology, and Temporality.” So I want to do a little catch-up in this post before a final – I hope – post in which I return to the idea that cultural evolution is driven by the need to assuage anxiety, an idea I have from David Hays and which I introduced into this series in the post, Culture as a Force in History: the United States of the Blues.

What I would like to do in this post is to be more explicit about how we get from a collection of individuals to a culturally coherent group, from individual minds to a “collective” mind in the meshwork of individuals held together by a common culture. From there I will give a more detailed account of the coordinators in the cultural evolutionary process, for it is the coordinators that make it possible. Then we’ll be ready for an explicit account of pleasure and anxiety. I’ll conclude with some remarks on the need for cultural stability before we can have cultural evolution.

Note: Most of the rest of this post is edited from materials I’ve published previously, either in Beethoven’s Anvil (chapters 3 and 4) or my working paper, Cultural Evolution, Memes, and the Trouble with Dan Dennett.

Coupling, Music and the Mesh

How then do we go about constructing a physically coherent account of a collective mind? What I did in the second and third chapters of Beethoven’s Anvil was to argue that when a group of people is engaged in making music together, and/or dancing together, that they are functioning as a collective mind. In this collective mind most of the signal pathways are inside brains and bodies and transmit signals electro-chemically. But some of the signal pathways exist between individuals, where the signals are transmitted as mechanical waves through the air. The nature of these two sets of signals – their speed, their content – must be such that the overall ensemble functions smoothly.

Note that when people are doing this, each gives up most of his or her individual freedom for the duration of the activity. If they are playing completely notated music, such as musicians in a symphony orchestra, then they agree to play what is written in the score. They also agree to follow the indications of the conductor and to coordinate their actions with their fellow musicians. If they are improvising jazz musicians, they aren’t committed to a specific score, though a given arrangement is likely to have some specified melodic lines and back up “riffs”, but they agree to the general conventions to be followed in each piece and they agree to be responsive to one another in the group.

This may seem obvious and self-evident, but it is this self-evident cooperation that allows us to treat the group as embodying a single coherent “mind.” There is only one source of “free” agency, and that is the group. Music is such a subtle business that, despite all this cooperation, the individuals still have quite a lot to keep them busy.

That’s the easy part of the argument. But I did something else, something more abstract and more subtle. I called on the neurobiology of Walter Freeman. Freeman uses the mathematics of complexity theory to study neural activity. That mathematics was originally developed by nineteenth century physicists to study thermodynamics. Continue reading

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Evolve an App Name

Edit: The results are out!

I’m working with the Language in Interaction project to create an App game about linguistic diversity.  It’s a game where you listen to several recordings of people talking and have to match the ones who are speaking the same language.  It’s quite a lot like the Great Language Game, but we’re using many lesser-known languages from the DOBES archive.

But first – we need a name.  Help us create one with the power of Iterated Learning!

Click to take part in our 1-minute experiment to evolve an app name.

We’ll throw some app names at you, you try to remember them, then we throw your names at someone else.

Here’s a screenshot of the App in development:

Drag2_demo

(P.S.: I’ve done this kind of thing before to evolve a band name)

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Cultural Beings, the Ontology of Culture, and a Return to Books and Blues

I haven’t forgotten my on-going series of posts on the direction of cultural evolution; you know, the one that started with Matt Jockers’ Macroanalysis? But I’ve been busy with other things. Here’s another post to add to that pile. I’m not yet burned out on culture, but lordy lordy I’m gettin’ there. But there’s a few more ideas I’ve got to get out there before I can hang up these particular shoes. If only for awhile.

* * * * *

What do I mean by cultural beings? To be honest, I’m not quite sure. Let’s start by being conservative about it – though just what “conservative” means amid this kind of intellectual craziness is a curious question – let’s say that novels, like those Jockers considered, are cultural beings. So are musical performances, like those driving American culture; they’re also cultural beings. Cultural beings are things like THAT, but note that THAT ranges over culture in general and not merely so-called high culture. After all, most of Jockers’ novels and most of those musical performances are not high cultural phenomena. Many are distinctly low and vulgar, while others are merely middlebrow.

I am using “cultural being” as a term of art. It designates not merely the cultural artifact, whether it is a long narrative imprinted in a codex, a musical composition inscribed on score paper, or even a performance merely floating in the air and then gone forever, except for memories of it. Those physical things are just packages or envelopes, other terms of art I’m hereby proposing. And those packages or envelopes “contain” coordinators, the cultural analog to biological genes.

When we read texts or listen to (even participate in) performances, the coordinator packages elicit phantasms in the mind/brain. It is the phantasm that gives pleasure, and so leads to a desire for repetition, or not, in which case the package that elicited it is forgotten. Those phantasms belong to cultural beings as well. If you will, the package of coordinators is the body of a cultural being while the phantasm is its soul.

The Ontology of Culture

When I talk about the ontology of culture, then, I mean these entities and the relations between them: cultural beings, packages or envelopes, coordinators, and phantasms. The relations between them are complex and subtle and I don’t pretend to grasp them, though I’ve been writing and thinking about the at least since my book on music, Beethoven’s Anvil, if not longer.

The overall relationship among them, however, is given by the evolutionary dynamic of blind variation and selective retention:

The evolution of cultural beings proceeds by blind variation among coordinators and selective retention of phantasms.

But what does it mean to retain a phantasm? Phantasms are (collective) mental events. They come and they go. How can they be retained?

They can’t. But they can be remembered and if the memory is compelling, one can re-create the phantasm. How do you do that? You re-experience the package of coordinators that gave rise to the phantasm in the first place. And so we have this modified formulation:

The evolution of cultural beings proceeds by blind variation among coordinators and selective retention of packages or envelopes.

Will that work? Will it do the job? I don’t know. I just thought it up.

Let us remember, however, that phantasms are the cultural analog to the biological phenotype. And what is retained in biological evolution is not the individual phenotypes. They all die and the matter of which they were composed rots. What’s retained is the phenotypic scheme, the Bauplan that emerges from a developmental process regulated by the genotype.

With that in mind, let’s move on. Continue reading

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Stone Age Minds (with Dr Kenny Smith and Dr Suilin Lavelle)

As part of the free online course, Philosophy and the Sciences, Dr Kenny Smith and Dr Suilin Lavelle have prepared a three-part video series on Evolutionary Psychology and Cultural Evolution called Stone Age Minds:

Clocking in at under 40 mins for the all three parts, the series provides a good primer on the basic principles underpinning modern evolutionary theory and how this relates to our minds, the environment and culture.

A heatmap showing an example language from one of the Shape Different condition chains at Generation 3. Vertically we have the labels produced and horizontally we have the stimuli. Colour represent token frequency that has been rescaled from 0-1 (darker representing higher frequency).

Languages adapt to their contextual niche (Winters, Kirby & Smith, 2014)

ResearchBlogging.orgLast week saw the publication of my latest paper, with co-authors Simon Kirby and Kenny Smith, looking at how languages adapt to their contextual niche (link to the OA version and here’s the original). Here’s the abstract:

It is well established that context plays a fundamental role in how we learn and use language. Here we explore how context links short-term language use with the long-term emergence of different types of language systems. Using an iterated learning model of cultural transmission, the current study experimentally investigates the role of the communicative situation in which an utterance is produced (situational context) and how it influences the emergence of three types of linguistic systems: underspecified languages (where only some dimensions of meaning are encoded linguistically), holistic systems (lacking systematic structure) and systematic languages (consisting of compound signals encoding both category-level and individuating dimensions of meaning). To do this, we set up a discrimination task in a communication game and manipulated whether the feature dimension shape was relevant or not in discriminating between two referents. The experimental languages gradually evolved to encode information relevant to the task of achieving communicative success, given the situational context in which they are learned and used, resulting in the emergence of different linguistic systems. These results suggest language systems adapt to their contextual niche over iterated learning.

Background

Context clearly plays an important role in how we learn and use language. Without this contextual scaffolding, and our inferential capacities, the use of language in everyday interactions would appear highly ambiguous. And even though ambiguous language can and does cause problems (as hilariously highlighted by the ‘What’s a chicken?’ case), it is also considered to be communicatively functional (see Piantadosi et al., 2012).  In short: context helps in reducing uncertainty about the intended meaning.

If context is used as a resource in reducing uncertainty, then it might also alter our conception of how an optimal communication system should be structured (e.g., Zipf, 1949). With this in mind, we wanted to investigate the following questions: (i) To what extent does the context influence the encoding of features in the linguistic system? (ii) How does the effect of context work its way into the structure of language?  To get at these questions we narrowed our focus to look at the situational context: the immediate communicative environment in which an utterance is situated and how it influences the distinctions a speaker needs to convey.

Of particular relevance here is Silvey, Kirby & Smith (2014): they show that the incorporation of a situational context can change the extent to which an evolving language encodes certain features of referents. Using a pseudo-communicative task, where participants needed to discriminate between a target and a distractor meaning, the authors were able to manipulate which meaning dimensions (shape, colour, and motion) were relevant and irrelevant in conveying the intended meaning. Over successive generations of participants, the languages converged on underspecified systems that encoded the feature dimension which was relevant for discriminating between meanings.

The current work extends upon these findings in two ways: (a) we added a communication element to the setup, and (b) we further explored the types of situational context we could manipulate.  Our general hypothesis, then, is that these artificial languages should adapt to the situational context in predictable ways based on whether or not a distinction is relevant in communication.

Continue reading

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Why Cultural Evolution Needs a Distinction Between “Genes” and “Phenotypes”

I’m thinking I’m about to burn out on cultural evolution, so this will be relatively short and informal.

* * * * *

Ever since I began thinking about a Darwinian process for cultural evolution back in the mid-1990s I’ve insisted on making a distinction between phenotypic entities (which I’m now calling “phantasms”) and genotypic entities (which I’m now calling “coordinators”). Why? My basic reason was to preserve the analogy between the cultural evolutionary process and biological.

That’s understandable, and it was a reasonable thing to do – back then. But there’s been a great deal of discussion about whether or not such a distinction needs to be made for cultural evolution, and if so: how do we make it? Some thinkers, like Dennett and Blackmore don’t make such a distinction at all, being content to theorize about memes, which are thus more like viruses than genes. To be sure, they’ve not gotten very far, nor for that matter has anyone else. But still, the issue must be faced, for there needs to be a better reason for such a distinction than the mere logic of analogy.

After all, what if the underlying logic of cultural evolution is different from that of biological evolution? What if there is no distinction comparable to the genotype-phenotype distinction?

My contention is that there is such a distinction and I’m now prepared to offer a reason for it:

Culture resides in people’s minds and the mind is in the head. We cannot read one another’s minds.

The environment to which cultural entities must adapt is the collective human mind. That’s been clear to me for a long time. And, of course, various conceptions of collective minds have been around for a long time as well. The problem is to formulate a conception in contemporary terms, terms which admit of no mystification.

I did that in the second and third chapters of Beethoven’s Anvil (2001) where I argued that when people make music together, and dance as well, their actions and perceptions are so closely coupled that we can think of a collective mind existing for the duration of that coupling. There are no mystical emanations engulfing the group. It’s all done through physical signals, electro-chemical signals inside brains, visual and auditory signals between individuals.

In this model the genetic elements of culture are the physical coordinators that support this interpersonal coupling. These coordinators are the properties of physical things – streams of sound, visual configurations, whatever – and as such are in the public sphere where everyone has access to them. Correspondingly, the phenotypic elements are the mental phantasms that arise within individual brains during the coupling. These phantasms are necessarily private though, in the case of music making, each person’s phantasm is coordinated with those of others.

If those phantasms are pleasurable ¬– I defined pleasure in terms of neural flow in chapter four of Beethoven’s Anvil – then people will be motivated to repeat the activity and those phantasms will thus be repeated. One of the factors that lead to pleasure is precisely the capacity to share the experience with others. The function of coordinators is to support the sharing of activities and experiences. Just as genes survive only if the phenotypes carrying them are able to reproduce, so coordinators survive only if they give rise to sharable phantasms.

Culture is sharable. That’s the point. If it weren’t sharable it couldn’t be able to function as a storehouse of knowledge and values.

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That, briefly and informally, is it. Obviously more needs to be done, a lot more. I can do some of it, though not now. But much of the heavy lifting is going to have to be done by people with technical skills that I don’t have.