Replicated Typo

Some Links #2

This week we all get to learn a new word, the potential origins of the written word and killing at a distance. Enjoy!

Archaeogenetics — yet another call for multi-discipline research? Yes, and the latest issue of Current Biology has a load of free (yes, free) papers on archaeogenetics. I haven’t had chance to read all of them, but it’s certainly worth checking out these two: Archaeogenetics — towards a ‘New Synthesis’? and The Genetics of Human Adaptation: Hard Sweeps, Soft Sweeps, and Polygenic Adaptation.
New Scientist discusses research into the discovery of primitive writing systems from 35,000 years ago. Obviously, this has massive implications for those of us who thought the seeds of writing were only starting to emerge approximately 5000-years-ago. The key paragraph: “What emerged was startling: 26 signs, all drawn in the same style, appeared again and again at numerous sites (see illustration). Admittedly, some of the symbols are pretty basic, like straight lines, circles and triangles, but the fact that many of the more complex designs also appeared in several places hinted to von Petzinger and Nowell that they were meaningful – perhaps even the seeds of written communication.” They’ve also got some pretty pictures.
If you’re looking for good news regarding the economy, then don’t go over to Washington’s Blog. He has a short post on Alan Greenspan’s assertion that we’re in the worst financial crisis ever.
I’ve been reading a lot of articles over at the brilliant blog, Emergent Fool. Of particular interest are posts relating to my recent article on cumulative culture and coordinated behaviour: Rafe Furst discusses three types of cooperation, cultural agency and complex systems concept summary. Meanwhile, Plektix writes about how human cultural transformation was triggered by dense populations.
Emergent Fool also led me to an in-depth essay by Professor Yaneer Bar-Yam on emergence and complexity: complexity rising: from human beings to human civilization, a complexity profile.
Lastly, American Scientist has a podcast on the evolution of the human capacity for killing at a distance. Here’s the summary: “Duke University anthropologist Steven Churchill presents his research on the evolutionary origins of projectile weaponry, and how weapon use changed interactions between humans and other species—including, perhaps, the Neandertals.”

Cumulative Culture Evolved to Rapidly Coordinate Novel Behaviours

In the deliberations over humanity and its perceived uniqueness, a link is frequently made between our ability to support a rich, diverse culture and the origin of complex human behaviour. Yet what is often overlooked in our view of these two, clearly connected phenomena is the thread that weaves them together: the ability to coordinate behaviour. We need only look at the products of our culture, from language to religion, to see that any variant we may deem successful is contingent on coordinating the behaviour of two or more individuals. Still, what is truly illuminating about this ability is that, far from being a uniquely human feature, the ability to coordinate behaviour is ubiquitous throughout the many organismal kingdoms.

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Guns, Germs and Predictable Reviews

If, like me, you generally like the Guardian’s science features, then please avoid reading Tim Radford‘s book club discussion of Jared Diamond‘s Guns, Germs and Steel. Ever since I noticed this book was on the Guardian’s reading list, it’s been an ongoing curiosity of mine as to how they will tackle the subject. Mainly because Diamond’s book, along with Richard Dawkins’ The Selfish Gene, urged me to move into studying evolution. Sadly, and perhaps not very surprisingly, you get little from the discussion bar an unequivocal acceptance of Diamond’s central thesis: that of environmental determinism.

Nowhere is there a mention of ideas that stand somewhat in opposition to Diamond’s, such as those in the 10,000 Year Explosion. Namely, the consequences of agriculture on recent human evolution, and the growing mountain of evidence supporting the contention that different human populations have adapted to their local environments.

And just to be clear: I think Diamond’s book is a well-written, scholarly account of human history, and it’s influence is not to be understated. But I also think he overlooked a large portion of the argument.

How Culture Shaped The Human Genome

The study of culture, cultural evolution, gene-culture coevolution and niche construction have all received much more attention over the last decade. So it’s nice to see Nature taking on-board a fascinating review by Kevin Laland, John Odling-Smee and Sean Myles about how culture shaped the human genome: bringing genetics and the human sciences together. It’s really worth reading for anyone interested in the interactions between biology and culture. In particular, I was pleased to see them put forward the notion of culture having accelerated recent evolution, contra Stephen J. Gould’s claim that “there’s been no biological change in humans for 40,000 or 50,000 years”. Here’s the abstract:

Researchers from diverse backgrounds are converging on the view that human evolution has been shaped by gene–culture interactions. Theoretical biologists have used population genetic models to demonstrate that cultural processes can have a profound effect on human evolution, and anthropologists are investigating cultural practices that modify current selection. These findings are supported by recent analyses of human genetic variation, which reveal that hundreds of genes have been subject to recent positive selection, often in response to human activities. Here, we collate these data, highlighting the considerable potential for cross-disciplinary exchange to provide novel insights into how culture has shaped the human genome.

Titanoboa… Pt 2.

As you can probably infer by the lack blog posts, the past few months I’ve abstained from writing anything on this website. Yet to my surprise, the average amount of visitors has been steadily increasing over the past few months, with the post receiving the most hits being Titanoboa… OMG!

I guess people like gigantic snakes.

Broca's Area and Hierarchical Structure Building

Considering I devoted two blog posts (pt.1 & pt.2) to Broca’s area and its role in processing hierarchically organised sequences, I’m happy report the following from a Talking Brains post on Disentangling syntax and intelligibility:

Hierarchical structure building can be achieved without Broca’s area involvement.

I’ve only just finished reading the post and, despite having some thoughts on the topic, I’m going to read the actual paper in question (Disentangling syntax and intelligibility in auditory language comprehension) before commenting. Especially since the authors, Friederici et al, don’t seem to arrive at the same conclusions as the bloggers over at Talking Brains. Still, as far as I can tell, this is only looking at syntactic information within speech, and doesn’t really tell us anything about the processing of hierarchically organised sequences in other linguistic (e.g. written language) and non-linguistic (e.g. tool manufacturing) domains.

Here’s the abstract for the paper in question:

Studies of the neural basis of spoken language comprehension typically focus on aspects of auditory processing by varying signal intelligibility, or on higher-level aspects of language processing such as syntax. Most studies in either of these threads of language research report brain activation including peaks in the superior temporal gyrus (STG) and/or the superior temporal sulcus (STS), but it is not clear why these areas are recruited in functionally different studies. The current fMRI study aims to disentangle the functional neuroanatomy of intelligibility and syntax in an orthogonal design. The data substantiate functional dissociations between STS and STG in the left and right hemispheres: first, manipulations of speech intelligibility yield bilateral mid-anterior STS peak activation, whereas syntactic phrase structure violations elicit strongly left-lateralized mid STG and posterior STS activation. Second, ROI analyses indicate all interactions of speech intelligibility and syntactic correctness to be located in the left frontal and temporal cortex, while the observed right-hemispheric activations reflect less specific responses to intelligibility and syntax. Our data demonstrate that the mid-to-anterior STS activation is associated with increasing speech intelligibility, while the mid-to-posterior STG/STS is more sensitive to syntactic information within the speech.

Some links #1

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

The journal Biolinguistics now has a blog. Whether or not this turns out to be interesting will obviously depend on the role they adopt for the blog. At the moment it just seems to be promoting various conferences and a summer school. I’ve added their RSS to google reader, so we shall see if anything worth while pops up.
Peter Frost over at Evo and Proud has written a fascinating article about the late Claude Lévi-Strauss and his view that “cultural differences have, over time, produced biological differences”.
Babel’s Dawn is producing a ridiculous amount of insightful articles. In particular, you should check out: Is anything universal in language? It covers a great paper (click here for a draft copy) by Nicholas Evans and Stephen C. Levinson, which knocks down the perpetuated myth of language universals.
Be sure to check out The Adventures of Auck, a blog by a friend, and fellow Welshman, at Edinburgh University. He’s written two insightful pieces on colour perception in bilinguals. Part one and part two.
Hat tip to Shared Symbolic Storage for directing me towards a review of Michael Tomasello‘s book Why we cooperate? My personal view: it’s a by-product of our ability to coordinate perception and behaviour (but that’s for a future post).
Edge poses the question: How is the internet changing the way you think? Plenty of good responses. Particularly amusing was Andy Clark’s reply: What kind of dumb question is that?

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.

Falling miserably back to Earth

I just watched the first episode of the BBC’s new show Defying Gravity, and it is absolutely awful. Clichéd characters, boring plot, and a completely unrealistic setting (it’s set in 2052, which seems to have not moved on from 2009 — the obvious exception being space travel). However, it did remind me of a recent post by one of my favourite writers, Charles Stross:

There’s an implicit feedback between such a situation and the characters who are floundering around in it, trying to survive. For example: You want to deflect that civilization-killing asteroid? You need to find some way of getting there. It’s going to be expensive and difficult, and there’s plenty of scope for human drama arising from it. Lo: that’s one possible movie in a nutshell. You’ve got the drama — just add protagonists.

I use a somewhat more complex process to develop SF. I start by trying to draw a cognitive map of a culture, and then establish a handful of characters who are products of (and producers of) that culture. The culture in question differs from our own: there will be knowledge or techniques or tools that we don’t have, and these have social effects and the social effects have second order effects — much as integrated circuits are useful and allow the mobile phone industry to exist and to add cheap camera chips to phones: and cheap camera chips in phones lead to happy slapping or sexting and other forms of behaviour that, thirty years ago, would have sounded science fictional. And then I have to work with characters who arise naturally from this culture and take this stuff for granted, and try and think myself inside their heads. Then I start looking for a source of conflict, and work out what cognitive or technological tools my protagonists will likely turn to to deal with it.

Star Trek and its ilk are approaching the dramatic stage from the opposite direction: the situation is irrelevant, it’s background for a story which is all about the interpersonal relationships among the cast. You could strip out the 25th century tech in Star Trek and replace it with 18th century tech — make the Enterprise a man o’war (with a particularly eccentric crew) at large upon the seven seas during the age of sail — without changing the scripts significantly. (The only casualty would be the eyeball candy — big gunpowder explosions be damned, modern audiences want squids in space, with added lasers!)

TV sci-fi sucks.

N.B. They just started jabbering on about natural selection and completely missed the point. So I’ll repeat: TV sci-fi sucks.

What conclusions can we draw from Neanderthal DNA pt.2

4. Nuclear DNA: Forays into 3 billion base pairs

4.1 Before Vi-80

The Vindija-80 (Vi-80) specimen is an important find for geneticists: it yielded a minimally contaminated sample and provided those first steps into Neanderthal genomics.

Previously, attempts at retrieving ancient nuclear DNA sequences proved to be a notoriously difficult process, plagued with problems of degradation, contamination and chemical damage (Hofreiter et al., 2001). Researchers also need to contend with quantities of nuclear genome available: for every nuclear genome there are approximately several hundred mtDNAs (Green et al., 2008). The severity of these problems, especially contamination, is magnified through Neanderthal genetic similarity with humans (Green et al., 2006). This is troubling because nuclear DNA presents far less variability than mtDNA (Russell, 2002). As a result, huge stretches of nuclear sequences are required to find a significant number of polymorphisms (ibid). Such implications meant that discovering endogenous DNA sequences requires sifting through a large corpus of “[…] more than 70 Neanderthal bone and tooth samples from different sites in Europe and western Asia” (Green et al., 2006, pg. 331).

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What conclusions can we draw from Neanderthal DNA pt.1

In recent times, genetic technology has progressed sufficiently to elucidate upon some of the questions normally preserved for archaeologists. One such question concerns the fate of a group of hominins that roamed Europe and East Asia for at least 250,000 years. During this time, this species adapted and endured some of the harshest environments on offer, all while showing signs of a unique culture. Only for them to suddenly disappear from the fossil record approximately 30,000 years before present (BP) (cf. Barton et al. 2007). So, what happened to our closest evolutionary relatives, the Neanderthals?

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