Roles in Cultural Selection: Replicators, Interactors, and Beneficiaries, or, Where’s the Memes?

May 21, 2013 in Evolution

Once again, cultural evolution, and the problem of memes: What are they? Where are they? What do they do? While the general case does interest me, culture is so various that it is impossible to think about it directly. One has to think about specific cases. As details are important, I want to choose a fairly specific case, that of jazz in mid-20th-Century America. I want you to imagine that you’re in a jazz club in, say, Philadelphia, in, say, mid-October of 1952. It’s 1:30 in the morning, and the tune is Charlie Parker’s “Dexterity.” The piano player counts it off–ah one, ah two, one two three four

But we’re getting ahead of ourselves. We need a little conceptual equipment before considering the example. It’s the conceptual equipment that’s in question. Make no mistake, the concept of memes is conceptual equipment, and it’s confused and confusing.

Roles in Cultural Selection

Genes and phenotypes play certain roles in a more or less standard account of biological evolution. The phenotype interacts with the environment, where it either succeeds or fails at reproduction, depending on the “fit” between its traits and that environment. Where the phenotype is successful at reproduction, it is the genes which are said to carry heredity from one generation to the next.

In one very widespread account genes are said to be replicators. That is to say, replication is the role they play in evolutionary change. Here’s what Peter Godfrey-Smith has to say about that (The Replicator in Retrospect, Biology and Philosophy 15 (2000): 403-423.):

In The Selfish Gene (1976), Richard Dawkins had argued that individual genes must be seen as the units of selection in evolutionary processes within sexual populations. This is primarily because the other possible candidates, notably whole organisms and groups, do not “replicate.” Organisms and groups are ephemeral, like clouds in the sky or dust storms in the desert. Only a replicator, which can figure in selective processes over many generations, can be a unit of selection.

At the same time Dawkins coined the term “meme” to name entities filling the replicator role in cultural evolution. Later on he used the term “vehicle” to designate the entity that interacts with the environment. In biological evolution it is phenotypes that are the vehicles. In cultural evolution, well, that’s a matter of some dispute. And that more general dispute–what are the roles in cultural evolution and what kinds of things occupy them?–is what interests me.

However, I don’t particularly like the term “vehicle.” As Godfrey-Smith has noted, following others, it is a gene-centric term, characterizing what entities do from the so-called “gene’s eye” perspective. I’d prefer a more neutral perspective and so will use a term coined by Richard Hull, “interactor.” Here are definitions as Godfrey-Smith gives them:

Replicator: an entity that passes on its structure largely intact in successive replications.
Interactor: an entity that interacts as a cohesive whole with its environment in such a way that this interaction causes replication to be differential. Read the rest of this entry →

The myth of linguistic diversity

May 16, 2013 in Uncategorized

There was a debate today between Peter Hagoort and Stephen Levinson on ‘The Myth of Linguistic Diversity”.  Hagoort arguing the case for universalist accounts.  He admitted that language does exhibit a large amount of diversity, but that this diversity is constrained.  He argued that linguistics should be interested in which universal mechanisms explain the boundary conditions for linguistic diversity.  The most likely domain in which to find these mechanisms is the brain.  It comes with internal structure that defines the boundary conditions on the surface structures of human behaviours.  These boundary conditions include the learnability of input, and that language is processed incrementally and under time constraints.  Brains operate under these constraints so that linguistic processing of all languages happens in roughly the same processing stages.  Hagoort argued that proponents of a diversity approach to linguistics think that variation is unbounded or constrained only by culture.  While there is variation between individuals and between languages, it is the general types that we should be focussed on.

In contrast, Levinson suggested that we should be moving away from the picture of the modal individual with a fixed language architecture.  Instead, we should embrace population thinking and recognise the variation inherent at every level of language from typology to processing and brain structures.  While languages are constrained by the processing structures of the brain, these processing structures are plastic and adapt to the language and cultures in which they are embedded.  Adults lose the ability to distinguish sounds that are not part of their language.  Recent work on linguistic planning using eye-tracking shows that the elements of a scene that speakers attend to before starting to speak differs with the canonical word order of their language.  More fundamentally, brain structures can be affected by cultural experience, such as bilingualism or singing (indeed, the effect of bilingualism on processing shows that variation itself is a fundamental constraint).  So, brains do constrain learning and processing, but are themselves subject to constraints from interaction between individuals.  Brains also change over evolutionary time, adapting to a range of pressures.  Therefore, there is a complex ecology of systems that co-evolve to define the constraints on language, and understanding these systems requires focussing on diversity.

Hagoort conceded that there was impressive variation at each level, but wondered what was meant by “fundamental” differences.  For instance, how important is the precise neural architecture of an individual?  Even within the variation pointed out, complex linguistic processing isn’t being done in the thalamus, and this is a constraint that sets a boundary on variation.  Hagoort might have pointed out that, if there was so much variation between individuals, how do they communicate so effectively and how does basic interaction happen so easily between diverse individuals?  This points to brain processing universals that explain the constraints on language.

Both sides agreed that the basic aim of any science, including linguistics, is to discover general principles that explain the data.  However, are researchers focussing on the same data?  What is the object of study that linguistics are trying to find generalisations for?  It seems to me that the debate came down to what each proponent thought was the domain that was most likely to yield general explanations.  Hagoort suggests that we should be focussed on brain structures and processing in the individual.  Levinson, on the other hand, suggests that the interaction between individuals is a key domain (e.g. the interaction engine).  Proponents of cultural evolution such as Simon Kirby might argue that cultural transmission is a key domain.  It’s possible that the most relevant ‘universals’ in each of these domains may be very different.  A constructive step would be to describe how each of these domains constrain the other.  For instance, constraints on language processing in the brain certainly constrain interaction between individuals, but the requirements of interaction may affect how processing is employed.

There were some good points from the floor, including Peter Seuren pointing out that neither view was particularly close to proving their point, since proving universals, or their absence is very difficult.  A paper under review by Steven Piantadosi and Edward Gibson attempts to answer whether it is possible in principle or practice to amass sufficient evidence for a statistical test that would demonstrate a universal.  They conclude that it is possible in principle, but that there are not enough datapoints (languages) in order to achieve the required statistical power.  There was also an appeal for the study of diversity for the sake of diversity – that there are different motivations for explaining phenomena in the world, and that one of them is to understand human diversity.

The general message:  Proponents of universals need to take diversity into account, and proponents of diversity need to be more specific about how diversity maps onto processing and how different domains of language co-evolve.

Language Evolution Coursera Proxy

May 14, 2013 in language evolution, Resources

There is not currently a coursera on Language Evolution, so as a vague substitute, I thought I’d do a run down of places on the internet you can find some pretty decent free lectures on the evolution of language by some pretty big names.

1) The first are the videos of the plenaries from last year’s EvoLang conference in Kyoto. Unfortunately the page that did host these is here and now displays an error message: http://ocw.kyoto-u.ac.jp/international-conference-en/31 (I’ve posted the link incase they fix it).

FORTUNATELY, I still have the direct links to all the videos so here they are:

1 Massimo, Piattelli-Palmarini
Three Models (and a Half) for the Description of Language Evolution
Video
2 Minoru Asada
Towards Language Acquisition by Cognitive Developmental Robotics
Video
3 Cedric Boeckx
Homo Combinans
Video
4 Simon Kirby
Why Language Has Structure: New Evidence from Studying Cultural Evolution in the Lab and What It Means for Biological Evolution
Video
5 Jenny Saffran
Out of the Brains of Babes: Domain-general Learning Mechanisms and Domain-specific Systems
Video
6 Simon Fisher
Molecular Windows into Speech and Language
Video
7 Russell Gray
The Evolution of Language Without Miracles
Video
8 Rafael Núñez
The Irreducible Semantic Communicative Drive
Video
9 Tetsuro Matsuzawa
Outgroup: The Study of Chimpanzees to Know the Human Mind
Video
10 Tom Griffiths
Neutral Models for Language Evolution。
Video
11 Terrence Deacon
Neither Nature nor Nurture: Coevolution, Devolution, and Universality of Language
Video

(Though I’ve completely lost the videos for the biolinguistics workshop videos hosted on the same site, so if anyone has these links please send them to me, or just comment. Thanks.)

2) On the CARTA website you can find videos of speakers such as Terence Deacon talking about Symbolic Communication: Why is Human Thought so Flexible? as well as V.S. Ramachandran, Colin Renfrew and Patricia Churchland.

3) The videos from 2011′s ProtoLang can be viewed here: http://www.protolang.umk.pl/videos_and_links

There’s a link to the videos from 2009′s protolang at the bottom of that too, but they all seem to be broken. But you can actually still find them by searching for the author’s name on http://tv.umk.pl/

For example, searching Bart de Boer, you can find: http://tv.umk.pl/#movie=521

4) YouTube.

Highlights include Simon Kirby’s inaugural lecture at Edinburgh University, Kenny Smith at the University of Southampton earlier this year, more Terence Deacon, Luc Steels on robots and loads of other stuff, I am sure you are capable or googling the names of some language evolution folk.

Also, you can watch bbc horizon’s why do we talk featuring Techumseh Fitch, Simon Kirby and others here: http://www.youtube.com/watch?v=75XxjJYuV7I&list=PL9DD35E568234CA7F

And by request in the comments: Peter Richerson – How Possibly Language Evolved http://www.youtube.com/watch?v=zxJMtZUaeZU

If anyone else has some good video resources please add them in the comments!

More on Dennett on Memes

May 8, 2013 in Evolution, language evolution

Still thinking about Dan Dennett’s conception of memetics. He’s got an article in the Encyclopedia of Evolution (Oxford 2005), “New Replicators, The” that’s worth looking at.

Some bits. From the beginning:

…evolution will occur whenever and wherever three conditions are met: replication, variation (mutation), and differential fitness (competition).

In Darwin’s own terms, if there is “descent [i.e., replication] with modification [variation]” and “a severe struggle for life” [competition], better-equipped descendants will prosper at the expense of their competitors. We know that a single material substrate, DNA (with its surrounding systems of gene expression and development), secures the first two conditions for life on earth; the third condition is secured by the finitude of the planet as well as more directly by uncounted environmental challenges.

The first question, then, is whether or not these conditions are met by human culture. Dennett thinks they are and so do I.

From the end, however:

Do any of these candidates for Darwinian replicator actually fulfill the three requirements in ways that permit evolutionary theory to explain phenomena not already explicable by the methods and theories of the traditional social sciences? Or does this Darwinian perspective provide only a relatively trivial unification?

We do not yet know. But are the prospects for non-triviality good enough to warrant considerable investment of conceptual time and energy? And so

We should also remind ourselves that, just as population genetics is no substitute for ecology—which investigates the complex interactions between phenotypes and environments that ultimate yield the fitness differences presupposed by genetics—no one should anticipate that a new science of memetics would overturn or replace all the existing models and explanations of cultural phenomena developed by the social sciences. It might, however, recast them in significant ways and provoke new inquiries in much the way genetics has inspired a flood of investigations in ecology. Read the rest of this entry →

The best ‘broken telephone’ picture?

May 7, 2013 in Uncategorized

It’s the unwritten rule of every talk on cultural evolution:  there must be at least one picture of someone whispering into someone else’s ear.  This represents language being passed on from one generation to the next, with the language possibly changing (like in the child’s game broken telephone or chinese whispers).  This classic image often makes an appearance:

gossip

However, most are boring old stock images.  So, I’m setting a challenge:  who can find the most awesome ‘broken telephone’ picture?

This is my submission:

Tarantino_Swinton_Manson_ILM_whisper

Image by Craig Barritt / Getty Images, found at The 45 Most Legendary Pictures Ever Taken.

Dan Dennett on Words in Cultural Evolution

May 6, 2013 in language evolution

I’ve been reading around in Dan Dennett’s papers and found this one, The Cultural Evolution of Words and Other Thinking Tools (Cold Spring Harbor Symp Quant Biol, Vol. LXXIV, August, 2009). To be sure, I disagree with his use of the meme concept. To be sure, his use is pretty standard and Dennett, in the standard way, claims more for it than can be justified by the current state of our knowledge and theorizing, but this paper is excellent despite that problem.

As the title indicates, Dennett focuses his attention on words and does so in a way that usefully brings their mystery, if you will, though mystery is rather low on Dennett’s intellectual agenda.

What then are words? Do they even exist? This might seem to be a fatuous philosophical question, composed as it is of the very items it asks about, but it is, in fact, exactly as serious and contentious as the claim that genes do or do not really exist. Yes, of course, there are sequences of nucleotides on DNA molecules, but does the concept of a gene actually succeed (in any of its rival formulations) in finding a perspicuous rendering of the important patterns amidst all that molecular complexity? If so, there are genes; if not, then genes will in due course get thrown on the trash heap of science along with phlogiston and the ether, no matter how robust and obviously existing they seem to us today.

For what it’s worth, I have it on good authority that there are languages which lack a word corresponding to our concept of word, though they generally have a word roughly corresponding to our concept of utterance (you can find this observation in, e.g., Alfred Lord, The Singer of Tales). That doesn’t bear directly on the point Dennett is making in those words as lacking a word for this is that really existing phenomenon is common enough, but it does indicate that words do have a rather diffuse or abstract character that makes it difficult to understand what they are and how they operate.

A bit later Dennett continues:

A promise or a libel or a poem is identified by the words that compose it, not by the trails of ink or bursts of sound that secure the occurrence of those words. Words themselves have physical “tokens” (composed of uttered or heard phonemes, seen in trails of ink or glass tubes of excited neon or grooves carved in marble), and so do genes, but these tokens are a relatively superficial part or aspect of these remarkable information structures, capable of being replicated, combined into elaborate semantic complexes known as sentences, and capable in turn of provoking cognitive, emotional, and behavioral responses of tremendous power and subtly.

I particularly like his phrase in that first sentence, “the trails of ink or bursts of sound that secure the occurrence of those words.” That secure the occurence, that’s nice. “Anchor” might also work, that anchor the occurence of those words in an utterance or a written text, as though the ink or sound were a tether holding the airy nothings of meaning and syntax to the ground. Read the rest of this entry →

Gender, language and economic power: another spurious correlation?

May 2, 2013 in Uncategorized

A paper from the Berkeley economic history laboratory published online last week finds a correlation between speaking a language with grammatical gender distinctions and the economic empowerment of women.  Gay, Santacreu-Vasut and Shoham (2013) find that women in countries with languages that make gender distinctions are less likely to participate in the labour market or politics and less able to get credit or own land.

The study uses a series of regressions to demonstrate robust correlations between grammatical gender and various economic variables from a range of databases.  The gender variables include whether a language has a sex-based gender system, how the genders are used in pronouns, the intensity of the gender system (languages with 2 genders vs languages with 1 or more than 2 genders) and whether gender is assigned semantically or formally.  The correlations control for geographical variables (distance from the equator), climate (tropics, frost days, access to the sea), history of colonisation, continent, religion and cultural beliefs and values.  The findings include statistics such as “Having a sex-based gender system decreases the female labor force participation rate by 13 pp % relative to the base-line value in countries with no gender system”.

The approach is very similar to Keith Chen’s study of future tense and economic savings behaviour, and uses some of the same data including the world atlas of language structures (WALS) and the World Values Survey.  Indeed, Gay et al. find that “women living in countries whose dominant language marks gender more intensively are less likely than men to save”.  The paper follows other studies on the cultural transmission of agricultural technology and the role of women in society (Alesina, Guiliano & Nunn, 2011, see here).

Read the rest of this entry →

“Music and the Origins of Language. International Summer School on Agent-based Computational Models of Creativity”.

April 29, 2013 in language evolution

Find call for Participation below.

“Music and the Origins of Language. International Summer School on Agent-based Computational Models of Creativity”.

15 – 20 September 2013, Cortona, Italy
http://ai.vub.ac.be/events/cortona-2013

The Evolutionary Linguistics Association (ELA) is proud to announce its second summer school in Cortona on Music and the Origins of Language. The school is intended for postdocs, lecturers and predocs with a background in computer science and a strong interest in music and the origins of language.

The summer school will be held in Cortona, Italy from Sunday 15 September to Friday 20 September 2013. Lectures, activities and meals are all collocated in Hotel Oasi and the Palazzone di Cortona. Participants will all stay at Hotel Oasi.

The summer school has a wide-ranging program of background lectures introducing concepts from biology, anthropology, psychology, music theory and linguistics that are helpful to understand the nature of creativity, the role and intimate relations between language and music, and the mechanisms underlying cultural evolution. It further contains technical lectures on the fundamental computational components required for language processing as well as technical ateliers to learn how to set up evolutionary linguistics experiments. Participants have the opportunity to present their latest research in a poster session. Embedded in the school is an ERC workshop of the Flow Machines project on musical style and composition. The school also features artistic ateliers in which participants create new creative works and engage in performance.

Interested researchers can apply by following the registration information that is available on the website. There are a limited number of scholarships available that cover participation and accommodation fees.

It receives support from FP7 PRAISE and INSIGHT projects, the euCognition Network of Excellence and the ESF project DRUST.

For information and queries, please visit the website http://ai.vub.ac.be/events/cortona-2013/ or email cortona2013@ai.vub.ac.be.

Numerical vs. analytical modelling

April 22, 2013 in Mathematical Modelling, Modelling, Science

ResearchBlogging.org

Since its resurgence in the 90s Multi-agent models have been a close companion of evolutionary linguistics (which for me subsumes both the study of the evolution of Language with a capital L as well as language evolution, i.e. evolutionary approaches to language change). I’d probably go as far as saying that the early models, oozing with exciting emergent phenomena, actually helped in sparking this increased interest in the first place! But since multi-agent modelling is more of a ‘tool’ rather than a self-contained discipline, there don’t seem to be any guides on what makes a model ‘good’ or ‘bad’. Even more importantly, models are hardly ever reviewed or discussed on their own merits, but only in the context of specific papers and the specific claims that they are supposed to support.

This lack of discussion about models per se can make it difficult for non-specialist readers to evaluate whether a certain type of model is actually suitable to address the questions at hand, and whether the interpretation of the model’s results actually warrants the conclusions of the paper. At its worst this can render the modelling literature inaccessible to the non-modeller, which is clearly not the point. So I thought I’d share my 2 cents on the topic by scrutinising a few modelling papers and highlight some caveats, and hopefully also to serve as a guide to the aspiring modeller!

Read the rest of this entry →

Iterated learning using Youtube videos and speech synthesis

April 8, 2013 in Uncategorized

This is a guest post by Justin Quillinan (of Chimp Challenge fame).

Cast your reminisce pods back a few days and recall Sean’s iterated learning experiment using the automated transcription of YouTube videos. The process went as follows:

1. Record yourself saying something.
2. Upload the video to YouTube
3. Let it be automatically transcribed (usually takes about 10 minutes for a short video)
4. Record yourself saying the text from the automatic transcription
5. Go to 2

Sean took a short extract from Kafka’s Metamorphosis and found that, as in human iterated learning experiments, both the error rate and compression ratio decreases with successive iterations. He also found that the process resulted in a text with longer and more unique words.

I was curious to see whether we could remove human participants entirely and run computer generated speech through this automated transcription. Here’s the process:

1. Generate an audio file from some text using a speech synthesis program;
2. Generate a transcription of the audio file;
3. Repeat from 1. with the new transcription.

Screen Shot 2013-04-08 at 10.00.28

Read the rest of this entry →