EvoLang: Post-conference awards

So EvoLang is over.  But if you missed any of it, the papers are still available online.  In celebration of the new digital format, I’ve chosen a number of papers for some post-conference awards (nothing official, just for fun!).

Most viewed papers

The proceedings website received 6,000 page hits, most of them during the conference itself.  Here are the top 3 most viewed pages:

The Low-complexity-belt: Evidence For Large-scale Language Contact In Human Prehistory?
Christian Bentz

Semantic Approximation And Its Effect On The Development Of Lexical Conventions
Bill Noble and Raquel Fernández

Evolution Of What?
Christina Behme

Most news coverage

Two papers were covered by Science magazine:

Dendrophobia In Bonobo Comprehension Of Spoken English
Robert Truswell (read the article here)

The Fidelity Of Iterated Vocal Imitation
Pierce Edmiston , Marcus Perlman and Gary Lupyan (read the article here)

Most cited paper

One of the advantages of the papers being accessible online, and before the conference, is that other people may cite them.  Indeed, on the day EvoLang ended, I received a short piece to review which cited this paper, which therefore gets the prize:

Anatomical Biasing Of Click Learning And Production: An MRI And 3D Palate Imaging Study
Dan Dediu and Scott Moisik

Best paper by an academic couple

By my count, there were 4 papers submitted by academic couples.  My favorite was a great collaboration on a novel topic:  the paper by Monika Pleyer and Michael Pleyer on taking the first steps towards integrating politeness theory and evolution (it was also shortlisted for best talk).

The Evolution Of Im/politeness
Monika Pleyer and Michael Pleyer

Best supplementary materials

8 accepted papers included supplementary materials, which are available on the website.  These range from hilarious image stimuli (my favorite: a witch painting a pizza), to a 7-page model explanation, through to netlogo code and raw data and analysis scripts.  But I’m afraid I’m going to choose my own paper’s supplementary materials for including videos of people playing Minecraft.  For science.

Deictic Tools Can Limit The Emergence Of Referential Symbol Systems
Elizabeth Irvine and Sean Roberts

EvoLang Preview: Language Adapts to Interaction workshop

LATI_Wheel

The first day of EvoLang includes several workshops (full list here) to which all attendees are invited.  Gregory Mills and I are running a workshop on language evolution and interaction, and the schedule and papers are now available online.

Language Adapts to Interaction, 08:30-13:30, Monday, 21st March, 2016, New Orleans

Language has been shown to be adapted to constraints from many domains such as production, transmission, memory, processing and acquisition. These adaptations and constraints have formed the basis for theories of language evolution, but arguably the primary ecology of language is interaction – face-to-face conversation. Taking turns at talk, repairing problems in communication and organising conversation into contingent sequences seem completely natural to us, but are in fact highly organised, tightly integrated systems which are not shared by any other species. Therefore, the infrastructure for interaction may provide an insight into the origins of our unique communicative abilities.  The emerging picture is that the infrastructure for interaction is an evolutionary old requirement for the emergence of a complex linguistic system, and for a cooperative, cumulative culture more generally.  That is, Language Adapts to Interaction.

The keynote talk is given by John Haviland, who covers an emerging sign language called Z, and argues that interactional tools such as gaze, pointing and attention management form the basis of both aspects of interaction such as turn taking, but also grammatical features in the language.

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EvoLang Preview: Morphological Redundancy and Survivability

This is a preview of the talk Redundant Features Are Less Likely To Survive: Empirical Evidence From The Slavic Languages by Aleksandrs Berdicevskis and Hanne Eckhoff.  Tuesday 22nd March, 14:30, room D.

One of the methodological trends of this year’s EvoLang seems to be intelligent exaptation. What I mean by this is that people do research on language evolution using tools that were developed for a completely different purpose. Examples include using zombies to observe the emergence of languages under severe phonological constraints, Minecraft to investigate the role of pointing in the emergence of language and EvoLang to study EvoLang. In addition to that, Hanne Eckhoff and I use syntactic parsers to quantify morphological redundancy.

The basic idea is to put to test an assumption that redundant features are more likely to disappear from languages, especially if social factors favour the loss of excessive complexity. The problem is that nobody really knows what is redundant in real languages and what is not. We can define a feature as redundant if it is not necessary for successful communication, i.e. if hearers can infer the meanings of the messages they receive without using this feature. It is, however, still a long way from this definition to a quantitative measure. In theory, one could run psycholinguistic experiments, in practice, it is a difficult and costly venture (I tried).

In this paper, we replace humans with a dependency parser. For those who are not into computational linguistics: a parser is a program which can automatically identify (well, attempt to identify) the syntactic structure of a given sentence. A typical parser is first trained on a large number of human-annotated sentences. After its learning is over, it can parse non-annotated sentences on its own, relying on the information about the form of every word, its lemma, part of speech, morphological features and the linear order of words — just like a human being. If we remove a certain feature from its input and compare performance before and after the removal, we can estimate how important (=non-redundant) the feature was.

redundancy_preview
If we remove all information about, say, dative from the parser’s input (to the left), it will have harder time to understand that the phrase two masters is an oblique object.

We test whether this measure is any good by running a pilot study with the Slavic language group. We estimate the redundancy of morphological features in Common Slavic (Common Slavic itself has left no written legacy, but we happen to have an excellent treebank of Old Church Slavonic, which is often used as a proxy) and try to predict which features are likely to die out in 13 modern Slavic languages. While redundancy is not of course a sole determiner of the survivability, it turns out be a fairly good predictor.

Come to the talk to hear about fierce morphological competitions! They are friends, dative and locative, almost brothers, but if only one can stay alive, which will sacrifice itself? The perfect participle is an underdog past tense, its frequency negligible compared to that of its rivals, the aorist and the imperfect, but does its high non-redundancy score give it some hope?

 

Aleksandrs Berdicevskis is a postdoc in computational historical linguistics at an edge of the world (namely The Arctic University of Norway in the city of Tromsø) with a PhD in sociolinguistics from the University of Bergen, MA in theoretical linguistics from Moscow State University, two years’ experience in science journalism, two kids and a long-standing interest in language evolution.
The first question he usually gets from new acquaintances is about the spelling of his name. The first name is a common Russian name (Aleksandr-) with the obligatory Latvian inflectional marker for nominative masculine singular (-s). The full form is used in formal communication only, otherwise he is usually called Sasha (the Russian hypocorism for Aleksandr) or, for simplicity’s sake, Alex.

EvoLang Preview: Using Minecraft to explore Language Evolution

Replicated Typo is doing a series of previews for this year’s EvoLang conference.  If you’d like to add a preview of your own presentation, get in touch with Sean Roberts.

At this year’s EvoLang Liz Irvine and I will be talking about how pointing can inhibit the emergence of symbolic communication.

Usually, pointing is thought to help the process of bootstrapping a symbolic system.  You can point to stuff to help people agree on what certain symbols refer to.  This process has been formalised in the ‘naming game’ (see Matt Spike’s talk):

  1. I request an object by naming it (with an arbitrary symbol)
  2. You guess what I mean and give me an object
  3. I point to the object that I meant you to give me (feedback)
  4. We remember the name that referred to this object

This game is the basis for many models of the emergence of shared symbolic systems, including iterated learning experiments (e.g Feher et al., and Macuch Silva & Roberts).  Here’s some robots playing the naming game in Luc Steels’ lab:

Robots use pointing to draw attention to objects in a naming game, see here.

However, the setup of these experiments assumes one crucial thing: that the individuals can’t use pointing to make the request in the first place.  Most experiments are set up so that participants must communicate symbolically before they can use pointing.  If you allowed pointing to be used in a naming game, then it would probably go something like this:

  1. I point at the object I want.
  2. I request an object by naming it (with an arbitrary symbol)
  3. You guess what I mean and give me an object
  4. I point to the object that I meant you to give me (feedback)
  5. We remember the name that referred to this object

That is, if we’re good enough at pointing then we don’t need a symbolic language for this task.

Of course, there must have been some task in our evolutionary history that provided a pressure for us to develop language.  We set out to explore what kind of task this might have been by running an experiment in Minecraft.

Continue reading “EvoLang Preview: Using Minecraft to explore Language Evolution”

1st issue of The Journal of Language Evolution: discussion on tone and humidity

The origins of language, and how they change over time, are tricky topics.  We can’t travel back in time to observe how it happened, and we’re only just beginning to understand the range of variation in existing languages.  Traditionally, the study of language evolution was more of a philosophical enterprise, with many educated guesses and a lot of debate about theoretical distinctions.  But these days it’s clear that a much wider approach is needed.  Thinking about how so many diverse ways of communicating could have emerged in a single species (and that species alone) involves thinking about topics as diverse as genetics, animal communication, cultural evolution, emerging sign languages, and the history of human migration and contact (even Chomsky recently wrote of the importance of acquisition, pragmatics, computer science and neuroscience in understanding the language faculty!).

The new Journal of Language Evolution will tackle these issues by reaching out to new areas of research and by embracing new quantitative methods, as Dan Dediu discusses in the editorial of the first issue.  The issue includes an introduction to the linguistic diversity of planet Earth by Harald Hammarstrom, which demonstrates how important the work of language documentation (especially of endangered languages) is for shaping our ideas about what evolved.  Bodo Winter and also provide an introduction to mixed models and growth curves, which is becoming an increasingly important tool in the language sciences.  Extending the topics to pragmatics, Cat Silvey reviews Thom Scott Phillips’ book Speaking our Minds.

Climate and Language Evolution

But if this isn’t deep enough into the frontiers of language evolution for you, there is also a debate on humidity and tone.  Caleb Everett, Damian Blasí and myself discuss the potential effects of our ecology on language evolution.  This includes obvious differences such as some languages having more specific words for relevant climatic factors (not just words for snow, but watch this space for news on that front), to the way the climate affects population movement.  We focussed on one controversial idea: dry air affects phonation accuracy, so some sounds should be harder to produce accurately in dry climates.  Over a long period of time, this might lead to languages changing to avoid these sounds.

Here’s a simple diagram of what we mean:

Continue reading “1st issue of The Journal of Language Evolution: discussion on tone and humidity”

Poeppel’s “parts list” for language, and why there’s more to it than syntax

This year’s Nijmegen lectures were given by David Poeppel on his work linking language processing to low-level neural mechanisms.  He called for more “muscular” linguists to step up and propose a “parts list” of linguistic primitives that neuro researchers could try and detect in the brain.  In this post, I cover the generativist answer to this, as proposed by Norbert Hornstien, who appeared as a panelist at the Nijmegen lectures, and why it bothered me (TLDR: I think there’s more to language science than syntax, and other areas can also draw up a “parts list”).

Continue reading “Poeppel’s “parts list” for language, and why there’s more to it than syntax”

EvoLang proceedings are now online

This year, the proceedings of the Evolution of Language conference will appear online.  The first group of papers are already up:

Browse the EvoLang Electronic Proceedings

The move to self-publishing is a bit of an experiment, but hopefully it’ll mean that the papers are more accessible to a wider audience.  To aid this, the papers are published under Creative Commons licenses.  Some papers also include supplementary materials.

The full list of papers will be updated as revisions come in, but here are some interesting papers available so far:

Continue reading “EvoLang proceedings are now online”

Visiting opportunities to study Language Evolution at the MPI for Psycholinguistics

The MPI for Psycholinguistics in Nijmegen, Netherlands is inviting scholars to visit in 2016 and 2017 to participate in Language Evolution research.

Under the running guest programme of the Institute, special opportunities are available in 2016-2017 for visitors – both senior scholars and post-docs – participating in the research theme “Evolution of Language”, starting at any time in 2016. The theme will be hosted by the Language & Cognition department (run by Stephen Levinson) in collaboration with the other departments at the Institute.

The MPI for Psycholinguistics and its partners in Nijmegen offer an exciting environment in which to explore the evolution of language, both in its biological and cultural dimensions, and the interactions between them. The MPI has departments in language and genetics, the neurobiology of language, the psychology of language, language and cognition, and (in development) the acquisition of language. The MPI is a partner in the Donders Institute for Brain, Cognition & Behaviour, Centre for Language Studies, and the Language in Interaction consortium, which bring together many different perspectives on language evolution.

Senior Visitorships are available for any period from one month up to one year until the end of 2017, and Postdocs are available for up to one year starting at any time in 2016.

More details here.

EvoLang Workshop: Language Adapts to Interaction

This week the workshops appearing at EvoLang have been announced.   Participation is free to those attending the main conference.

Gregory Mills and I are running a workshop on language evolution and interaction.  Details are on the workshop website, including a call for papers.

LATI_Wheel

Language Adapts to Interaction

Language has been shown to be adapted to constraints from many domains such as production, transmission, memory, processing and acquisition. These adaptations and constraints have formed the basis for theories of language evolution, but arguably the primary ecology of language is interaction – face-to-face conversation (Levinson, 2006). Taking turns at talk, repairing problems in communication and organising conversation into contingent sequences seem completely natural to us, but are in fact highly organised, tightly integrated systems (Sacks et al., 1974) which are not shared by any other species. Therefore, the infrastructure for interaction may provide an insight into the origins of our unique communicative abilities (Mills, 2014a; Micklos, 2014).

Indeed, recent studies on interaction have shown that an approach that emphasises interaction can sharpen our understanding of linguistic universals (Kendrick et al., 2014; Dingemanse et al., 2015), ontogeny and acquisition (Hilbrink, et al. 2015; Vogt, 2014), on-line processing constraints (Bögels et al., 2015) and animal signalling (Levinson & Holler, 2014).

The emerging picture is that the infrastructure for interaction is an evolutionary old requirement for the emergence of a complex linguistic system, and for a cooperative, cumulative culture more generally. These issues are also being integrated into computational models of the cultural evolution of linguistic systems (Vogt and Haasdijk, 2010; Roberts, & Levinson, 2015) and are being explored through studies of experimental semiotics (Mills, 2014b; Christensen et al., 2016).

This workshop is interested in addressing the following questions:

  • How did the infrastructure for interaction emerge and how did it shape the emergence of language?
  • What evidence is there that language structures show adaptation to interaction?
  • How do interactional constraints interact with other domains such as processing?
  • What are the limits of interactional abilities in non-human animals?

For instructions on how to submit, please see the Abstract Submissions page.

References

Bögels, S., Magyari, L., & Levinson, S. C. (2015). Neural signatures of response planning occur midway through an incoming question in conversation. Scientific Reports, 5: 12881.

Christensen, P., Fusaroli, R., and Tylén, K. (2016). Environmental constraints shaping constituent order in emerging communication systems: Structural iconicity, interactive alignment and conventionalization. Cognition, 146:67–80.

Dingemanse, M., Roberts, S. G., Baranova, J., Blythe, J., Drew, P., Floyd, S., Gisladottir, R. S., Kendrick, K. H., Levinson, S. C., Manrique, E., Rossi, G., & Enfield, N. J. (2015). Universal Principles in the Repair of Communication Problems. PLoS One, 10(9).

Hilbrink, E., Gattis, M., & Levinson, S. C. (2015). Early developmental changes in the timing of turn-taking: A longitudinal study of mother-infant interaction. Frontiers in Psychology, 6: 1492.

Kendrick, K. H., Brown, P., Dingemanse, M., Floyd, S., Gipper, S., Hayano, K., Hoey, E., Hoymann, G., Manrique, E., Rossi, G., & Levinson, S. C. (2014). Sequence organization: A universal infrastructure for action. 4th International Conference on Conversation Analysis. UCLA, CA.

Levinson, S. (2006). On the human interaction engine. In Enfield, N. and Levinson, S., editors, Roots of Human Sociality: Culture, Cognition and Human Interaction, pages 39–69. Oxford: Berg.

Levinson, S. C., & Holler, J. (2014). The origin of human multi-modal communication. Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences, 369(1651): 2013030.

Micklos, A. (2014) The Nature of Language in Interaction. Proceedings of the 10th Evolution of Language conference. World Scientific: Vienna, Austria.

Mills, G. (2014a) Establishing a communication system: Miscommunication drives Abstraction. Proceedings of the 10th Evolution of Language conference. World Scientific: Vienna, Austria.

Mills, G. J. (2014b). Dialogue in joint activity: complementarity, convergence and conventionalization. New Ideas in Psychology, 32:158–173.

Roberts, S. G. & Levinson (2015) On-line pressures for turn-taking constrain the cultural evolution of word order. Workshop on Cognitive Linguistics and the Evolution of Language, International Cognitive Linguistics Conference, Newcastle University, UK.

Sacks, H., Schegloff, E. A., and Jefferson, G. (1974). A simplest systematics for the organization of turn-taking for conversation. Language, 40(4):696–735.

Vogt, P. (2014) Language acquisition through interactions: A cross-cultural corpus of multimodal interactions with 1-to 2-years old infants. 8th International Conference on Construction Grammar. Osnabrück University, Germany.

Vogt, P. and Haasdijk, E. (2010). Modeling social learning of language and skills. Artificial Life, 16(4):289–309.

The effect of climate on individual speech: Does Larry King use more vowels when it’s warmer?

This weekend I appeared in an NPR article about Ian Maddieson and Christophe Coupe’s work on the effects of climate and ecology on the sound systems of languages.  I haven’t read the study itself, but I did get to see the slides that Maddieson and Coupe presented this week at the Acoustical Society of America.  Essentially, they find that speech sounds have high efficacy – adaptation to being transmitted and received in the local ecology.  Specifically, languages tend to be more sonorous (less ‘consonant heavy’) in warmer places with more tree cover.  This makes sense, since these kind of sounds are better at cutting through these obstacles.

I was interviewed for about an hour, but the quotes from me in the piece are actually a bit out of context.  For instance, I claim that this is the first study of its kind, when there have been several studies which looks at climate and language (including one I co-authored with Caleb Everett and Damian Blasi).  But, to be fair, Maddieson and Coupe’s study is probably the one with the greatest range of ecological variables and most sophisticated linguistic measure (although I’m not sure yet how they control for historical relatedness).

You can read about the study in the article above, but I wanted to address another thing I’m quoted as saying.  The interviewer asked if it was possible to see these effects in a single language or a single speaker, and I said that it was very unlikely, but that I’d tried to do this with transcripts of Larry King.  I went on to say that I absolutely wouldn’t publish this because it was a crazy idea that nobody would believe.

But now the cat’s out of the bag,  so here’s what I found.

Does Larry King use more vowels when it’s warmer?

If we see language change as natural selection operating on individual utterances in conversation (a la Croft and others), then we should be able to see selective pressures at work in the utterances of an individual speaker.  This should also apply to the influence of climate.  Given enough data, you should be able to see an individual adapting over the seasons.  In light of Maddieson and Coupe’s hypothesis, speakers should use proportionately more vowels compared to consonants when it’s warmer.

CNN provides transcripts for every show broadcast between 2000 and 2012.  Larry King has done an interview practically every day on the show ‘Larry King Live’ (which has been used before in linguistic studies), so I extracted Larry King’s speech transcripts (excluding the guest’s speech, mentions of the location of the studio and the guest’s names).  For each transcript I counted the frequency of each letter, then calculated the ratio of vowels (aeiouy) to consonants.    Then, for each air date, I found the actual temperature and humidity data for that date and the location of the show (CNN studios in LA). The show is occasionally recorded in Washington DC or New York.  I tried to detect these automatically and matched them with the climate measures for the CNN studios in those cities.

There are about 3,500 transcripts over 11 years, about 90% of which were aired on consecutive days. (I know nothing about this show, and am a bit surprised by its frequency!  I’ll have to check whether the transcripts include repeats).

Here is a depiction of the results for temperature and humidity:

CVRatio_by_Temp

The Black lines show King’s vowel ratio (higher = more vowels) and bars are 95% confidence intervals around the mean for each week of the year.  The maximum and minimum temperature are shown in red and blue.  Below is a similar graph for specific humidity.

CVRatio_by_specHumidity

Surprisingly, there is some variation in proportion of vowels, and it looks like there’s a trend in the right direction.

To analyse the data, I used a linear mixed effects model, predicting vowel ratio by (log) text length and maximum temperature, with random effects for year and each week (580 separate weeks, to try to control for topical issues).

Maximum temperature significantly improves the fit of the model over a null model with text length (Chi Squre = 23.7, df = 1, p < 0.00001).

Model estimates: 
                       Estimate Std. Error t value 
(Intercept)           4.100e-01  8.114e-04   505.3 
maxTempC.loc          9.628e-05  1.973e-05     4.9 
text.total.log.center 5.340e-03  8.400e-04     6.4 

King uses proportionately more vowels when it’s warmer.  The effect is very small: On average, there is a difference of about 15 vowels used in an hour of conversation between summer and winter.  A model with location-specific maximum temperature improves the model fit over one with just LA-specific maximum temperature (Chi Sqaured = 11.59, df=1 , p=0.0007).

Of course, the temperature is not independent from day to day, so I also tried a lagged regression, predicting vowel ratio by text length (total) and maximum temperature of the recording location (maxTempC.loc).  Lagging back in time by days.

Coefficients: 
                          Estimate Std. Error t value Pr(>|t|) 
(Intercept)              4.076e-01  7.342e-04 555.073  < 2e-16 *** 
d[lag.0, ]$textLength    3.772e-07  6.715e-08   5.618 2.08e-08 *** 
d[lag.0, ]$maxTempC.loc  1.008e-04  3.300e-05   3.055  0.00227 ** 
d[lag.1, ]$maxTempC.loc  5.009e-05  3.812e-05   1.314  0.18893 
d[lag.2, ]$maxTempC.loc  1.549e-07  3.840e-05   0.004  0.99678 
d[lag.3, ]$maxTempC.loc -7.405e-05  3.809e-05  -1.944  0.05195 . 
d[lag.4, ]$maxTempC.loc -2.418e-06  3.300e-05  -0.073  0.94159 

The temperature of actual day is still significant, taking into account previous days.  Note that the coefficient is negative after 3 lagged days. (please forgive the rough analysis- it’s all I have left after my computer broke recently).

I’m not really sure what to make of this.  Given the data above, there is an argument that King is adapting the way he speaks to the climate.  However, a LOT more needs to be done in order to show this.  There are several confounding factors, such as the show being recorded in an air conditioned studio, the topics or guests might be different, there might be seasonal topics or key-words which affect the results (though one might argue that the lexicon for things related to cold climates has adapted).  The graphs show big jumps around week 32, which I can’t explain yet.  Then there is the question of the mechanism – how exactly is King adapting?  By choice of alternative words, or constructions?  And, of course, the transcripts are orthorgraphic.  And, of course, the idea is crazy.

Still, I think it’s amazing that we’re now in a position where we can even start asking these kind of questions with data.