James Winters

Some Links #15: Empires of the Word & anti-Babel

Empires of the Word & anti-Babel. It’s a few days old now but I’ve only just had time to read it. Anyway, check out Razib’s review of Empires of the Word: A Language History of the world. Lots of information for budding historical linguists and those intrigued by language spread and extinction. Particularly relevant is the following paragraph:

As I indicated above Empires of the Word is rather thin on robust generalizations. But one point which the author mentions repeatedly is that the rise and fall of languages of great expanse and utility is the norm, not the exception. In particular, Nicholas Ostler takes time out to emphasize that languages which spread via trade often do not have long term staying power. Portuguese, Aramaic, Punic and Sogdian would fall into this category (the later success of Portuguese was a matter of rice and empire in Brazil). It seems that mercantile communities are too ephemeral, that successive historical shocks inevitably result in their decline when there isn’t a peasant demographic reservoir or imperial power which imposes it by fiat. Even those languages which eventually spread beyond traders and gain cultural and political cachet may fall from grace. Greek is the best case of this. It was the dominant language of the Roman East, and spoken as far as modern Pakistan, and studied in Dark Age Ireland. By the early modern period it was a strange and foreign language in the West, and with the rise of Islam in the east it lost its cultural glamor, and even those Christians in Arab lands who were Melkite, Greek Orthodox who adhered to the theological position of Constantinople, became Arab in speech and identity (in greater Syria the Greek Orthodox have been instrumental in the formulation of Arab nationalism).

Opening a bibliography database for human evolution. Again, it’s been a few days since this was posted, but I’d advise anyone interested in human evolution visit John Hawks recently announced database. The bibliography section also has an RSS feed which provides a chronological list (newest first).

In which I apply for a job as a homeopath… Dave over at Anomalous Disaster has a great little post on him applying for a position at NHS Tayside for a homeopathic specialist. This is from the very same health board who recently brought us the sacking of 500 staff. So Dave decided to apply, which, at a cushy £68,000 salary, is definitely a job worth pursuing — after all, it can’t be that hard to dispense magic beans and provide a pseudo-scientific air of authority. Here is part of his letter of application:

The original research that I have published means that I am familiar with the body of published work on homeopathy, and the many meta-analyses and systematic reviews conducted on it. The fact that these conclude that homeopathy is no more effective than a similarly administered placebo will not bother me whilst I am taking advantage of some of the excellent salmon fishing to be found in the Tayside region. Indeed, given the fact the position only calls for the successful applicant to attend two sessions per week, I should imagine I would have plenty of time to indulge in a bit of fishing.

Click here to apply.

Selfish Sounds: Darwinism in linguistics. A brief(ish) article on the work of historical linguist, Nikolaus Ritt, and how words and sounds compete for the purpose of being replicated. Specifically, it looks at how the sound shapes of English words have gradually evolved:

Good examples of such phenomena are sets of changes which are obviously directed but unfold over time spans that are impossible to even survey by individual speakers. They have come to be known as ‘drifts’. A case of such a drift seems to have affected the sound shapes of English words (or better: lexical morphemes, i.e. the smallest linguistic units that carry meaning). Over time their shapes seem to have gradually evolved in a direction where they came to fit better into the rhythmical patterning that characterises English speech. “For instance, vowels in long words tended to be shortened over time, while vowels in short words tended to be lengthened. Thus, the rhythmic units they established became more uniform”, Nikolaus Ritt explains.

[…] From the evolutionary perspective this kind of development is best understood if one regards rhythm as an environmental constant in the linguistic world in which words and the sounds they are made up of have to survive and replicate. Because of the constant environmental pressure which rhythm exerts on them, the sound shapes of English words have gradually changed to become better adapted to the rhythmically structured utterances through which they get expressed and transmitted.

New Blog: Culture Evolves!

… Well, new to me at least. It’s run by Fiona Jordan of the Max Planck Institute for Psycholinguistics, and her latest post is an interview with one of my favourite researchers, Simon Greenhill (I didn’t know he designed a sudoku solving program). Also, after having done a little digging into her publications, I found the following forthcoming paper: The effect of population size and density on rates of linguistic evolution. Here is the abstract:

Evolutionary theory from population genetics predicts that demography may play an important role in determining the rate at which cultural and linguistic traits change over time. However, relatively few studies have explored this relationship for language at an appropriate scale and in a quantitative way, nor controlled for the problem of non-independence induced by the historical relationships between languages. Here we use phylogenetic trees of 351 Austronesian languages to test whether the rate of change in core vocabulary is affected by population size and population density. We detected a strong phylogenetic signal in both population size and density, indicating the need for historical control. We find a significant inverse relationship between lexical replacement and population size, no relationship with population density, and we confirm that splitting events influence lexical evolution. These results support the idea that a process analogous to genetic drift may be an important factor in lexical evolution. Furthermore, the strong phylogenetic signal in these demographic factors suggests that despite repeated population splits the social conditions that influence speech community size and density are maintained and inherited from one generation to the next.

I’m not going to say anything on a paper I haven’t yet read, other than it looks pretty cool and that more people should be considering the influence of demographic factors in linguistics.

Experiments in communication pt 2: Human Iterated Learning

In the last post, I discussed some of the literature into experimental communication, with the intention of then following it up by looking at recent experiments done at Edinburgh (and beyond). But as Hannah pipped me to the post, with a great overview of the wide range of experiments into language evolution, I’ll instead limit this to two relatively recent papers on Human Iterated Learning (Kirby et al., 2008; Cornish et al., 2009)

Drawing from experimental approaches found in Diffusion Chain and Artificial Language Learning studies, Kirby et al (2008) show that as a consequence of intergenerational transmission languages “culturally evolve in such a way as to maximize their own transmissibility: over time, the languages in our experiments become easier to learn and increasingly structured.” In these experiments a subject is exposed to an alien language, made up of two elements within a finite space: meanings (consisting of a picture with three discernible elements: colour, shape and movement) paired with signals (consisting of a string of letters). Importantly, the subject is only exposed to a set amount of meanings (SEEN items), after which they are then presented with a group of meanings (some SEEN, some UNSEEN) without the corresponding signal — the goal being that they provide a response (be it the correct version or not). On completion of forming the meaning-signal pairs the experiment is repeated, except this time the new subjects are trained on the data provided by the previous generation. This continues until the experiment is finished, which in this case happened at generation ten.

Continue reading “Experiments in communication pt 2: Human Iterated Learning”

More on Gene-culture coevolution

Ed Yong has a cool article on Genes and culture: OXTR gene influences social behaviour differently in Americans and Koreans. It has some interesting parallels, and contrasting conclusions, with my post last week. Key paragraphs:

Heejung Kim from the University of California has discovered a great example of this effect by studying a gene called OXTR (or the ‘oxytocin receptor’, in full). The gene creates a docking station for a hormone called oxytocin, which is involved in all sorts of emotions and social behaviours, from trust to sexual arousal to empathy.

Kim looked at a specific version of the OXTR gene, whose carriers are allegedly more social and sensitive. But this link between gene and behaviour depends on culture; it exists among American people, who tend to look for support in troubled times, but not in Korean cultures, where such support is less socially acceptable. Culture sets the stage on which the OXTR gene expresses itself.

OXTR varies from person to person, and the DNA ‘letters’ at particular spots can affect the way we behave. According to previous studies, people with a ‘G’ at one specific site tend to be more sensitive parents, more empathetic and less lonely than those with an ‘A’. But most of these studies have been done with white, Western people who are hardly representative of the world at large – in fact, they’re positively W.E.I.R.D. [My emphasis]

Genetic Components and Cultural Differences: The social sensitivity hypothesis

Cultural differences are often attributed to events far removed from genetics. The basis for this belief is often based on the assertion that if you take an individual, at birth, from one society and implant them in another, then they will generally grow up to become well-adjusted to their adopted culture. Whilst this is more than likely true, even if there may be certain cultural features that may disagree with someone of a different ethnic background (e.g. degrees of alcohol tolerance), the situation is not as clear cut as certain political factions may have you believe. Yet, largely due to studies on gene-culture coevolution, we are now starting to understand the complex dynamics through which genes and culture interact.

First, a particular culture may exert selection pressures on genes that provide an advantageous benefit to the adoption of a particular cultural trait. This is evident in the strong selection of the lactose-tolerance allele due to the spread of dairy farming. Second, pre-existing gene distributions provide pressures through which culture adapts. Off the top of my head, one proposed example of this is a paper by Dediu and Ladd (2007), which looked at how the distribution of the derived haplotypes of ASPM and Microcephalin may have subtly influenced the development of tonal languages. The paper in question, however, is looking more broadly at culture. Specifically, the authors, Baldwin May and Matthew Lieberman, examine recent genetic association studies and how within-variation of genes involved in central neurotransmitter systems are associated with differences in social sensitivity. In particular, they highlight a correlation between the relative frequencies of certain gene-variants and the relative degree of individualism or collectivism within certain populations.

Continue reading “Genetic Components and Cultural Differences: The social sensitivity hypothesis”

Population Size and Rates of Language Change

In previous posts, I’ve looked at the relationship between cultural evolution and demography (see here, here and here). As such, it makes sense to see if such methods are applicable in language which is, after all, a cultural product. So, having spent the last few days looking over the literature on language and demography, I found the following paper on population size and language change (free download). In it, the authors, Søren Wichmann and Eric Holman, use lexical data from WALS to test for an effect of the number of speakers on the rate of language change. Their general findings argue against a strong influence of population size, with them instead opting for a model where the type of network influences change at a local level, through different degrees of connectivity between individuals. Here is the abstract:

Previous empirical studies of population size and language change have produced equivocal results. We therefore address the question with a new set of lexical data from nearly one-half of the world’s languages. We first show that relative population sizes of modern languages can be extrapolated to ancestral languages, albeit with diminishing accuracy, up to several thousand years into the past. We then test for an effect of population against the null hypothesis that the ultrametric inequality is satisified by lexical distances among triples of related languages. The test shows mainly negligible effects of population, the exception being an apparently faster rate of change in the larger of two closely related variants. A possible explanation for the exception may be the influence on emerging standard (or cross-regional) variants from speakers who shift from different dialects to the standard. Our results strongly indicate that the sizes of speaker populations do not in and of themselves determine rates of language change. Comparison of this empirical finding with previously published computer simulations suggests that the most plausible model for language change is one in which changes propagate on a local level in a type of network in which the individuals have different degrees of connectivity.

As I’m in the middle of several other things at the moment I don’t really have time to provide a thorough review of this paper. Having said that, I agree with their claim of population size being unlikely to account for rates of language change. I reckon their results would be stronger if they factored in population density. So those that are dense and large will change faster than those which are large and distributed. The main point being that population size and population density influence the degree of social interconnectivity. Nettle (1999), for instance, argues that “spreading an innovation over a tribe of 500 people is much easier and takes much less time than spreading one over five million people.” This is fairly reasonable if we are looking at the generation of a single innovation within each of these populations. However, if those 500 people are spread across a large distance, then their transmission chain is going to be stretched: effectively lowering the rate of transmission. The same applies for a population of five million individuals who are packed into a small area: Arguably, given the right conditions, we can arrive at a situation where a population of five million show greater levels of interconnectivity than 500. I think it’s this aspect, the level of social interconnectivity, which may be more relevant to the rate of language change (other things to test for, include: writing systems/literacy and inter-language contact).

Some Links #14: Can Robots create their own language?

Can Robots create their own language? Sean already mentioned this in the comments for a previous post. But as I’m a big fan of Luc Steels‘ work this video may as well go on the front page:

Speaking in Tones: Music and Language Partner in the brain. The first of two really good articles in Scientific American. As you can guess by the title, this article is looking at current research into the links between music and language, such as the overlap in brain circuitry, how prosodic qualities of speech are vital in language development, and the way in which a person hears a set of musical notes may be affected by their native language. Sadly, the article is behind a paywall, so unless you have a subscription you’ll only get to read the first few paragraphs, plus the one I’m about to quote:

In a 2007 investigation neuroscientists Patrick Wong and Nina Kraus, along with their colleagues at Northwestern University, exposed English speakers to Mandarin speech sounds and measured the electrical responses in the auditory brain stem using electrodes placed on the scalp. The responses to Mandarin were stronger among participants who had received musical training — and the earlier they had begun training and the longer they had continued training, the stronger the activity in these brain areas.

Carried to extremes: How quirks of perception drive the evolution of species. In the second good article, which by the way is free to view, Ramachandran and Ramachandran propose another mechanism of evolution in regards to perception:

Our hypothesis involves the unintended consequences of aesthetic and perceptual laws that evolved to help creatures quickly identify what in their surroundings is useful (food and potential mates) and what constitutes a threat (environment dangers and predators). We believe that these laws indirectly drive many aspects of the evolution of animals’ shape, size and coloration.

It’s important to note that they are not arguing against natural selection; rather, they are simply offering an addition force that guides the evolution of a species. It’s quite interesting, even if I’m not completely convinced by their hypothesis — but my criticisms can wait until they publish an actual academic paper on the subject.

A robotic model of the human vocal tract? Talking Brains links to the Anthropomorphic Talking Robot developed at Waseda University. Apparently it can produce some vowels. Here is a picture of the device (which looks like some sort of battle drone):

Y Chromosome II: What is its structure? Be sure to check out the new contributor over at GNXP, Kele Cable, and her article on the structure of the Y Chromosome. I found this sentence particularly amusing:

As you can see in Figure 1, the Y chromosome (on the right) is puny and diminutive. It really is kind of pathetic once you look at it.

Scientopia. A cool collection of bloggers have banded together to form Scientopia. With plenty of articles having already appeared it all looks very promising. In truth, it’s probably not going to be as successful as ScienceBlogs, largely because it doesn’t pay contributors and, well, nothing is ever going to be as big as ScienceBlogs was at its peak. This new ecology of the science blogosphere is well articulated in a long post by Bora over at A Blog Around the Clock.

Experiments in Communication pt 1: Artificial Language Learning and Constructed Communication Systems

Much of recent research in linguistics has involved the use of experimentation to directly test hypotheses by comparing and contrasting real-world data with that of laboratory results and computer simulations. In a previous post I looked at how humans, non-human primates, and even non-human animals are all capable of high-fidelity cultural transmission. Yet, to apply this framework to human language, another set of experimental literature needs to be considered, namely: artificial language learning and constructed communication systems.

Continue reading “Experiments in Communication pt 1: Artificial Language Learning and Constructed Communication Systems”

Selection on Fertility and Viability

So in my previous post on mathematical modelling I looked at viability selection and how it can be expressed using relatively simple mathematics. What I didn’t mention was fertility. My reasoning largely being because the post was already getting unwieldy large for a blog, and, from now on, I’m going to limit the length on these math-based posts. I personally find I get more out of small, bite-sized chunks of information that are easily digestible, than overloading myself by trying understand too many concepts all at once. With that said, I’ll now look at what happens when the two zygote types, V(A) and V(B), differ in their fertility.

A good place to start is by defining the average number of zygotes produced by each type as z(A) and z(B). We can then plug these into a modified version of the recursion equation I used in the earlier post:

So now we can consider both fertility and viability selection. Furthermore, this can be combined to give us W(A) = V(A)z(A) and W(B) = V(B)z(B):

Remember, , is simply the the average the fitness in the population, which can be used in the following difference equation:

That’s it for now. The next post will look at the long-term consequences of these processes.

Reference: McElreath & Boyd (2007). Mathematical Models of Social Evolution: A guide for the perplexed. University of Chicago Press. Amazon link.

Some Links #13: Universal Grammar Haters

Universal Grammar haters. Mark Lieberman takes umbrage with claims that Ewa Dabrowska’s recent work challenges the concept of a biologically evolved substrate for language. Put simply: it doesn’t. What their experiments suggest is that there are considerable differences in native language attainment. As some of you will probably know, I’m not necessarily a big fan of most UG conceptions, however, there are plenty of papers that directly deal with su ch issues. Dabrowska’s not being one of them. In Lieberman’s own words:

In support of this view, let me offer another analogy. Suppose we find that deaf people are somewhat more likely than hearing people to remember the individual facial characteristics of a stranger they pass on the street. This would be an interesting result, but would we spin it to the world as a challenge to the widely-held theory that there’s an evolutionary substrate for the development of human face-recognition abilities?

Remote control neurons. I remember reading about optogenetics awhile back. It’s a clever technique that enables neural manipulation through the use of light-activated channels and enzymes. Kevin Mitchell over at GNXP classic refers to a new approach where neurons are activated using a radio frequency magnetic field. The obvious advantage to this new approach being fairly straight-forward: magnetic-fields pass through brains far more easily than light. It means the new approach is a lot less invasive, without the need to insert micro-optical fibres or light-emitting diodes. Cool stuff.

Motor imagery enhances object recognition. Neurophilosophy has an article about a study showing that motor simulations may enhance the recognition of tools:

According to these results, then, the simple action of squeezing the ball not only slowed down the participants’ naming of tools, but also slightly reduced their accuracy in naming them correctly. This occured, the authors say, because squeezing the ball involves the same motor circuits needed for generating the simulation, so it interferes with the brain’s ability to generate the mental image of reaching out and grasping the tool. This in turn slows identification of the tools, because their functionality is an integral component of our conceptualization of them. There is other evidence that parallel motor simulations can interfere with movements, and with each other: when reaching for a pencil, people have a larger grip aperture if a hammer is also present than if the pencil is by itself.

On the Origin of Science Writers. If you fancy yourself as a science writer, then Ed Yong, of Not Exactly Rocket Science, wants to read your story. As expected, he’s got a fairly large response (97 comments at the time of writing), which includes some of my favourite science journalists and bloggers. It’s already a useful resource, full of fascinating stories and bits of advice, from a diverse source of individuals.

Some thoughts about science blog aggregation. Although it’s still hanging about, many people, including myself, are looking for an alternative to the ScienceBlogs network. Dave Munger points to Friendfeed as one potential solution, with him setting up a feed for all the Anthropology posts coming in from Research Blogging. Also, in the comments Christina Pikas mentioned Nature Blogs, which, I’m ashamed to say, I haven’t come across before.