Phonemic Diversity Supports a Serial Founder Effect Model of Language Expansion from Africa

Just read about an article on phoneme diversity via GNXP and Babel’s Dawn. Hopefully I’ll share some of my thoughts on the paper this weekend as it clearly ties in with work I’m currently doing (see here and here). Below is the abstract:

Human genetic and phenotypic diversity declines with distance from Africa, as predicted by a serial founder effect in which successive population bottlenecks during range expansion progressively reduce diversity, underpinning support for an African origin of modern humans. Recent work suggests that a similar founder effect may operate on human culture and language. here I show that the number of phonemes used in a global sample of 504 languages is also clinal and fits a serial founder-effect model of expansion from an inferred origin in Africa. This result, which is no explained by more recent demographic history, local language diversity, or statistical non-independence within language families, points to parallel mechanisms shaping genetic and linguistic diversity and supports an African origin of modern human languages.

Reference: Atkinson, Q.D (2011). Phonemic Diversity Supports a Serial Founder Effect Model of Language Expansion from Africa. Science 332, 346. DOI: 10.1126/science.1199295.

Update: I’ve given a lengthier response here.

Some Links #19: The Reality of a Universal Language Faculty?

I noticed it’s almost been a month since I last posted some links. What this means is that many of the links I planned on posting are terribly out of date and these last few days I haven’t really had the time to keep abreast of the latest developments in the blogosphere (new course + presentation at Edinburgh + current cold = a lethargic Wintz). I’m hoping next week will be a bit nicer to me.

The reality of a universal language faculty? Melodye offers up a thorough post on the whole Universal Grammar hypothesis, mostly drawing from the BBS issue dedicated Evans & Levinson (2009)’s paper on the myth of language universals, and why it is a weak position to take. Key paragraph:

When we get to language, then, it need not be surprising that many human languages have evolved similar means of efficiently communicating information. From an evolutionary perspective, this would simply suggest that various languages have, over time, ‘converged’ on many of the same solutions.  This is made even more plausible by the fact that every competent human speaker, regardless of language spoken, shares roughly the same physical and cognitive machinery, which dictates a shared set of drives, instincts, and sensory faculties, and a certain range of temperaments, response-patterns, learning facilities and so on.  In large part, we also share fairly similar environments — indeed, the languages that linguists have found hardest to document are typically those of societies at the farthest remove from our own (take the Piraha as a case in point).

My own position on the matter is fairly straightforward enough: I don’t think the UG perspective is useful. One attempt by Pinker and Bloom (1990) argued that this language module, in all its apparent complexity, could not have arisen by any other means than via natural selection – as did the eye and many other complex biological systems. Whilst I agree with the sentiment that natural selection, and more broadly, evolution, is a vital tool in discerning the origins of language, I think Pinker & Bloom initially overlooked the significance of cultural evolutionary and developmental processes. If anything, I think the debate surrounding UG has held back the field in some instances, even if some of the more intellectually vibrant research emerged as a product of arguing against its existence. This is not to say I don’t think our capacity for language has been honed via natural selection. It was probably a very powerful pressure in shaping the evolutionary trajectory of our cognitive capacities. What you won’t find, however, is a strongly constrained language acquisition device dedicated to the processing of arbitrary, domain-specific linguistic properties, such as X-bar theory and case marking.

Babel’s Dawn Turns Four. In the two and half years I’ve been reading Babel’s Dawn it has served as a port for informative articles, some fascinating ideas and, lest we forget, some great writing on the evolution of language. Edmund Blair Bolles highlights the blog’s fourth anniversary by referring to another, very important, birthday:

This blog’s fourth anniversary has rolled around. More notably, the 20th anniversary of Steven Pinker and Paul Bloom‘s famous paper, “Natural Language and Natural Selection,” seems to be upon us. Like it or quarrel with it, Pinker-Bloom broke the dam that had barricaded serious inquiry since 1866 when the Paris Linguistic Society banned all papers on language’s beginnings. The Journal of Evolutionary Psychology is marking the Pinker-Bloom anniversary by devoting its December issue to the evolution of language. The introductory editorial, by Thomas Scott-Phillips, summarizes language origins in terms of interest to the evolutionary psychologist, making the editorial a handy guide to the differences between evolutionary psychology and evolutionary linguistics.

Hopefully I’ll have a post on Pinker and Bloom’s original paper, and how the field has developed over these last twenty years, at some point in the next couple of weeks. I think it’s historical importance will, to echo Bolles, be its value in opening up the field: with the questions of language origins and evolution turning into something worthy of serious intellectual investigation.

Other Links

Hypnosis reaches the parts brain scans and neurosurgery cannot.

Are Humans Still Evolving? (Part Two is here).

The Limits of Science.

On Language — Learning Language in Chunks.

Farmers, foragers, and us.

Tweet This.

On Music and The Brain.

Why I spoofed science journalism, and how to fix in.

The adaptive space of complexity.

Some Links #18: GxExC

The depression map: genes, culture, serotonin, and a side of pathogens. Another new science blog network (Wired) and once again a new stable of good science writers. I’m particularly pleased to see that David Dobbs, a former SciBling and top science writer, has found a new home for Neuron Culture. I was also pleased to see he had written an article on studies into the interactions between genes and culture, namely: Chiao & Blizinsky (2009) and Way & Lieberman (2010). And I was even more pleased to see that he’d mentioned both mine and Sean’s posts on the social sensitivity hypothesis. Suffice to say, I was pleased.

Take home paragraph:

In a sense, these studies are looking not at gene-x-environment interactions, or GxE, but at genes x (immediate) environment x culture — GxExC. The third variable can make all the difference. Gene-by-environment studies over the last 20 years have contributed enormously to our understanding of mood and behavior. Without them we would not have studies, like these led by Chiao and Way and Kim, that suggest broader and deeper dimensions to what makes us struggle, thrive, or just act differently in different situations. GxE is clearly important. But when we leave out variations in culture, we risk profoundly misunderstanding how these genes — and the people who carry them — actually operate in the big wide world.
Razib also has some thoughts on the topic:
The same issues are not as operative when it comes to culture. Two tribes can speak different dialects or languages. If a woman moves from one tribe to another her children don’t necessarily speak a mixture of languages, rather, they may speak the language of their fathers. The nature of cultural inheritance is more flexible, and so allows for the persistence of more heritable variation at different levels of organization. Differences of religion, language, dress, and values, can be very strong between two groups who have long lived near each other and may be genetically similar.

Homo was born vocalizing. Babel’s Dawn links to a recently finished PhD thesis that supposedly argues for a relatively recent emergence for language (approx. 120,000 years ago). She defends her assertions by stating: “[…] all of the unique cognitive traits attributed to humans arose as the consequence of one crucial mutation, which radically altered the architecture of the ancestral primate brain.” I haven’t read the thesis, and I probably won’t as I’m already stretched in regards to my reading, but I’m completely unconvinced by the hopeful mutation hypothesis. Plus, as Bolles notes in his post, there is plenty of available evidence to the contrary.

Primed for Reading. Robert Boyd reviews Stanislas Dehane’s new book, Reading in the Brain: The Science and Evolution of a Human Invention, which I’ll be picking up soon. In the meantime, to give you a bit of background, I suggest you read Dehane’s (2007) paper on the Neuronal Recycling Hypothesis: the Cultural recycling of cortical maps. H/T: Gene Expression.

Through the looking glass (part 1). The Lousy Linguist reviews Guy Deutscher’s new book, Through the Language Glass: Why the World Looks Different in Other Languages, with the general takeaway message being that, in part one at least, one where the book is a bit science-lite. What really interested me, though, were these two paragraphs:

We discover quite quickly what Deutscher is doing as he begins to walk through complexity issues of “particular areas of language” (page 109), namely morphology, phonology, and subordination. And these last 15 pages are really the gem of Part 1. He shows that there is an interesting, somewhat illogical, entirely engaging but as yet unexplained set of correlations between speaker population size and linguistic complexity.

For example, languages with small numbers of speakers tend to have more morphologically rich grammars (hence one could claim that small = more complex). However, small languages with small numbers of speakers also tend to have small phonological inventories. Hmmm, weird, right? [My emphasis]

As those of you who read this blog will know: I don’t think it’s weird that small speaker populations also tend to have small phonological inventories.

Clothing lice out of Africa. A cool new paper by Troups et al which looks at the evolutionary history of clothing lice to provide specific estimates on the origin of clothing. Using a Bayesian coalescent modelling approach, they estimate that clothing lice diverged from head louse ancestors between 83,000 and 170,000 years ago. H/T: Dienekes.

Some Links #11: Linguistic Diversity or Homogeneity?

Linguistic Diversity = Poverty. Razib Khan basically argues, correctly in my opinion, that linguistic homogeneity is good for economic development and general prosperity. From the perspective of a linguist, however, I do like the idea of really obscure linguistic communities, ready and waiting to be discovered and documented. On the flip side, it is selfish of me to want these small communities to remain in a bubble, free from the very same benefits I enjoy in belonging to a modern, post-industrialised society. Our goal, then, should probably be more focused on documenting, as opposed to saving, these languages. Razib has recently posted another, quite lengthy post on the topic: Knowledge is not value-free.

When did we first ‘Rock the Mic’? A meeting of my two favourite interests over at the New York Times: Linguistics and Hip Hop. Ben Zimmer writes:

In “Rapper’s Delight,” the M.C. Big Bank Hank raps, “I’m gonna rock the mic till you can’t resist,” using what was then a novel sense of rock, defined by the O.E.D. as “to handle effectively and impressively; to use or wield effectively, esp. with style or self-assurance.” To be sure, singers in the prerap era often used rock as a transitive verb, whether it was Bill Haley promising, “We’re gonna rock this joint tonight,” or the bluesman Arthur “Big Boy” Crudup more suggestively wailing, “Rock me, mama.” But the M.C.’s of early hip-hop took the verb in a new direction, transforming the microphone (abbreviated in rap circles as mic, not mike) into an emblem of stylish display. Later elaborations on the theme would allow clothes and other accessories to serve as the objects of rock, as when Kanye West boasted in a 2008 issue of Spin magazine, “I rock a bespoke suit and I go to Harold’s for fried chicken.”

It’d be nice to see more stuff on linguistics and hip hop, and, having said that, I might write a bit on the subject. In fact, I would go as far as to say that hip hop is part of reason why I fell into linguistics: the eloquent word play encouraged, and perhaps moulded, my fascination with language. To demonstrate why, here’s a track by Maryland rapper, Edan, who certainly knows how to rock the mic:

Edan — One Man Arsenal

Life without language. Neuroanthropology provides yet another great read. This time it’s on the topic of life without language — something that’s always crept into my thoughts, yet seems impossible to imagine (as I’m already so embedded within a language-using society). The post goes on to discuss Susan Schaller and the case of a profoundly deaf Mexican immigrant who did not learn sign language:

The man she would call, ‘Ildefonso,’ had figured out how to survive, in part by simply copying those around him, but he had no idea what language was. Schaller found that he observed people’s lips and mouth moving, unaware that they were making sound, unaware that there was sound, trying to figure out what was happening from the movements of the mouths. She felt that he was frustrated because he thought everyone else could figure things out from looking at each others’ moving mouths.

One problem for Schaller’s efforts was that Ildefonso’s survival strategy, imitation, actually got in the way of him learning how to sign because it short-circuited the possibility of conversation. As she puts, Ildefonso acted as if he had a kind of visual echolalia (we sometimes call it ‘echopraxia’), simply copying the actions he saw

One Man’s Take on the Facts of the Matter. Babel’s Dawn takes a look at Tecumseh Fitch’s book, The Evolution of Language, and concisely explains a clear departure between two camps in evolutionary linguistics:

One clear difference between the scenarios is in the role of the individual in relation to language. Language is somehow built into the brain in Chomsky’s thought-first scenario, while it is learned from others in the topics-first approach. Empiricists, like Morten Christiansen and Nicholas Chater, see language as ‘out there’ to be learned while nativists, like Fitch and Chomsky, say there is an internal, I-language, and the language out there is merely the sum of all those little I-languages. How to settle the dispute? Look for factual evidence.

Some links #1

Having now returned, I feel a long list of links is needed to kick start things:

Right, that’s all I’ve got time for at the moment. Laptop battery is dying and my bladder is urging me towards the toilet.

Inconsistent, yes… But here are some links.

Okay, I promised a post a day and failed miserably. But it does say in my profile that I’m inconsistent. So it’s probably best to not believe everything I write, even if there is one valuable lesson in my broken promises: avoid targets. Anyway, I just thought I’d do a quick post on some articles that have caught my attention over the past few days:

Some changes

Now I’ve had a month-long break from blogging you may, or may not, have noticed a few changes to the blog, notably the inclusion of three additional features: Dissertation, Minifeed and Basic Concepts. So from now on in, I will definitely be adding a post every day, and hopefully a research-related post every week or so. But before all this happens, I really suggest you go over and visit Babel’s Dawn, as Mr Bolles is putting much of us slightly less prolific bloggers to shame with his coverage of the ways to protolanguage conference.

As for my own opinion of protolanguage: yes, it probably existed, but I really haven’t got any more to add at the moment. It is a topic I plan on returning to in another post, although I’m not really sure I can add anything extra to the current debate. There is one thing, though: I do find debates on concerning the transition of protolanguage into a fully fledged language a bit tiresome. I mean we’re not even fully sure as to the impact that writing systems have had on how we speak. Take Chomsky’s favourite topic of recursion. As far as I know, there is no evidence of complex recursion being present in languages prior to the emergence of writing systems. It may be the case that writing allowed for languages with no, or very circumscribed, recursion in their syntax to develop into a system that allows for embedding of indefinite complexity.

In truth, you can argue many features of language didn’t appear until the development of writing, as there is no solid record of languages existing prior to this invention. This is a problem all linguists face, and it does require a lot of assumptions to be made beforehand — some of which are reasonable (languages did exist before writing) and some of which may be construed as not reasonable (literate societies process language in the same way as non-literate societies).

Reading Round Up

Here’s some stuff I’ve been reading over the last month or so:

Okay, so that brings you up to date with my reading from May through to July. Next round up will cover August. How fascinating :-/


How do biology and culture interact?

In the year of Darwin, I’m not too surprised at the number of articles being published on the interactions between cultural change and biological evolution — this synthesis, if achieved, will certainly be a crucial step in explaining how humans evolved. Still, it’s unlikely we’re going to see the Darwin of culture in 2009, given we’re still disputing some of the fundamentals surrounding these two modes of evolution. One of these key arguments is whether or not culture inhibits biological evolution. That we’re seeing accelerated changes in the human genome seems to suggest (for some) that culture is one of these evolutionary selection pressures, as John Hawks explains:
Continue reading “How do biology and culture interact?”

Orangutans – probably more interesting than you

ResearchBlogging.orgIn the past few years there has been a recent spate of articles concerning orangutan intelligence. So, as I’m fairly bored, and in need of a break from university work, I’ve decided to write a bit of an essay on some of these finds.

Orangutans… They’re orange, right?

Correct; but Pongo pygmaeus abelii are so much more than just some arboreal orange ape that eats a lot of fruit. In fact, these great apes, the last surviving members of the genus Pongo, are highly resourceful and intelligent creatures, as evident in their ability to make and use tools, perform calculated reciprocity and even whistle a tune.

Continue reading “Orangutans – probably more interesting than you”