Guinea – Replicated Typo

Cultural artefact from 25,000 years ago is transmitted horizontally

Jonnie Hughes writes this week about his time spent with the Sepik tribes of Papua New Guinea (tipped off by Michael Pleyer). As part of a documentary series, Hughes visited them and then arranged for some of the tribe elders to visit Britain.

Of all the different technologies they encountered in Britain, the one that had the biggest impact was the idea of putting feathers on arrows to make them fly straight. The Sepik tribes used to achieve straight flight by using very heavy arrows alongside a reliable bowstring, but a five minute tutorial at an archery range in a local community centre gave them the technology to use lighter arrows. This meant that a hunter could carry more arrows and catch more prey.

Fletching technology is thought to date from as early as 25,000 years ago (Ötzi the Iceman had some 5,000 years ago), so seems like an unlikely candidate for a horizontally transmitted cultural artefact. Yet, with the world becoming more globalised, isolated communities are now exposed to not only modern technology, but the whole history of development that they can adopt. Indeed, as Hughes relates, the Sepik tribes are now on Facebook and have access to Wikipedia articles on archery.

This is, of course, a nightmare for people trying to study the transmission of cultural artefacts. What is the descent of fletching in the Sepik tribes? Is it horizontal transmission from modern-day British archers? Or, since the transmitter in question was re-creating traditional techniques, was it horizontal transmission from 15th century Britain (when archery was last widespread), or is it horizontal transmission from the original developers of fletching thousands of years ago? If they continue to borrow technology from wikipedia articles, which are written by dozens of people from all over the world, what is the transmission trajectroy of these ideas?

Along with stories like the hunger-suppressing properties of Hoodia plant being transmitted from hunter-gatherers from the Kalahari to industrialised western cultures, the descent of technologies does not seem to respect cultural or historical boundaries.

Given the theme of this story, it’s strange that Hughes’ new book gives the impression of re-inventing the wheel. The brilliantly titled “On the Origin of Tepees: The Evolution of Ideas (and Ourselves)” has the following introduction:

Throughout history, we humans have prided ourselves on our capacity to have ideas, but perhaps this pride is misplaced. Perhaps ideas have us. After all, ideas do appear to have a life of their own. And it is they, not us, that benefit most when they are spread. Many biologists have already come to the opinion that our genes are selfish entities, tricking us into helping them to reproduce. Is it the same with our ideas?

Jonnie Hughes, a science writer and documentary filmmaker, investigates the evolution of ideas in order to find out. Adopting the role of a cultural Charles Darwin, Hughes heads off, with his brother in tow, across the Midwest to observe firsthand the natural history of ideas—the patterns of their variation, inheritance, and selection in the cultural landscape. In place of Darwin’s oceanic islands, Hughes visits the “mind islands” of Native American tribes. Instead of finches, Hughes searches for signs of natural selection among the tepees.

An evolutionary approach to cultural transmission? What a great idea.

I may be too harsh here, it actually looks like quite a fun and interesting book. Perhaps there are already orders paced on Amazon by members of the Sepik tribes.

Hughes’ article: The tribesman who facebook friended me

Language is not necessary for analogy

Analogy is a trait thought to be uniquely human and the origin is largely unknown. Recent studies have suggested that some language trained apes can find relations between relations, which is thought to be what is at the root of analogy. However, a new study in the journal Psychological Science has tested baboons using shapes with matching features. These baboons were able to match pairs which had matching features and pairs which had no matching features.

The study was run by Joël Fagot of the Laboratoire de Psychologie Cognitive (CNRS/Université de Provence) and Roger Thompson of the Franklin & Marshall College (United States).

It has been hypothesised in the past that finding relations between relations is an ability only accessible by language, but these new findings with baboons cast doubt on this assertion.

The experiments were carried out on 29 baboons. The baboons were first shown two shapes on a screen. The baboons then touched one of these shapes and two other pairs of shapes appeared on the screen. To be successful at the task the baboons had to touch the pair representing the same relation as the initial pair. So if the first pair matched in a feature the baboon had to choose the pair which also had a matching feature, and avoid the pair where there was no matching feature, in order to gain a reward. This shows the inherent abilities behind analogy.

6 baboons correctly performed the task after thousands of trials of training showing that it is definitely within the abilities of old world monkeys to resolve analogy problems.

The researchers also revisited the same baboons with the same task a year later and the monkeys were much quicker at acquiring the task showing that they remembered what to do.

These results show that language is not necessary for analogy and leaves questions as to what might make this ability adaptive.

Reference

Fagot J, & Thompson RK (2011). Generalized Relational Matching by Guinea Baboons (Papio papio) in Two-by-Two-Item Analogy Problems. Psychological science PMID: 21934135

The USA: Most linguistically diverse country on the planet?

When asked to name a linguistically diverse place, I would have said Papua New Guinea, and if asked to name a stereotypically monolingual country, I would have named the USA. However, this recent report from the New York Times suggests that, due to its large immigrant population, New York harbours more endangered languages than anywhere else on Earth (tipped off from Edinburgh University’s Lang Soc Blog). From a field linguists’ point of view this may make discovery of and access to minority languages much easier (although may mean the end of exotic holidays). From a cultural evolution point of view, a more global community may mean a radically different kind of competition between languages. Nice video below:

The emergence of stable bilingualism in the lab: An experiment proposal

There is a huge amount of linguistic diversity in the world. Isolation and drift due to cultural evolution can explain much of this, but there are many cases where interacting groups use several languages. In fact, by some estimates, bilingualism is the norm for most societies. If one views language as a tool for communicating about objects and events, it seems strange that linguistic diversity should be maintained over time for two reasons. First, it seems more efficient, during language use, to have a one-to-one mapping between signals and meanings. In fact, mutual exclusivity is exhibited by young children and has been argued to be an innate bias and crucial to the evolution of a linguistic system. How or why do bilinguals over-ride this bias? Secondly, learning two language systems must be more difficult than learning one. What is the motivation for expending extra effort on learning an apparently redundant system?

Despite these obstacles, stable bilingualism exists in many parts of the world. How might these arise and be maintained? Continue reading “The emergence of stable bilingualism in the lab: An experiment proposal”

On Phylogenic Analogues

A recent post by Miko on Kirschner and Gerhart’s work on developmental constraints and the implications for evolutionary biology caught my eye due to the possible analogues which could be drawn with language in mind. It starts by saying that developmental constraints are the most intuitive out of all of the known constraints on phenotypic variation. Essentially, whatever evolves must evolve from the starting point, and it cannot ignore the features of the original. Thus, a winged horse would not occur, as six limbs would violate the basic bauplan of tetrapods. In the same way, a daughter language cannot evolve without taking into account the language it derives from and language universals. But instead of viewing this as a constraint which limits the massive variation we see biologically or linguistically between different phenotypes, developmental constraints can be seen as a catalyst for regular variation.

A pretty and random tree showing variation among IE languages.

Looking back over my courses, I’m surprised by how little I’ve noticed (different from how much was actually said) about reasons for linguistic variation. The modes of change are often noted: <th> is fronted in Fife, for instance, leading to the ‘Firsty Ferret’ instead of the ‘Thirsty Ferret’ as a brew, for instance. However, why the <th> is fronted at all isn’t explained beyond cursory hypothesis. But that’s a bit besides the point: what is the point is that phenotypic variation is not necessarily random, as there are constraints – due to the “buffering and canalizing of development” – which limit variation to a defined range of possibilities. There clearly aren’t any homologues between biological embryonic processes and linguistic constraints, but there are developmental analogues: the input bottleneck (paucity of data) given to children, learnability constraints, the necessity for communication, certain biological constraints to do with production and perception, etc. These all act on language to make variation occur only within certain channels, many of which would be predictable.

Another interesting point raised by the article is the robustness of living systems to mutation. The buffering effect of embryonic development results in the accumulation of ‘silent’ variation. This has been termed evolutionary capacitance. Silent variation can lay quiet, accumulating, not changing the phenotype noticeably until environmental or genetic conditions unmask them. I’ve seen little research (not that I don’t expect there to be plenty) on the theoretical implications of the influence of evolutionary capacitance on language change – in other words, how likely a language is to make small variations which don’t affect language understanding before a new language emerges (not that the term language isn’t arbitrary based on the speaking community, anyway). Are some languages more robust than others? Is robustness a quality which makes a language more likely to be used in multilingual settings – for instance, in New Guinea, if seven languages are mutually indistinguishable, is it likely the that local lingua franca is forced by its environment to be more robust in order to maximise comprehension?

The article goes on about the cost of robustness: stasis. This can be seen clearly in Late Latin, which was more robust than the daughter languages as it was needed to communicate in different environments where the language had branched off into the Romance languages, and an older form was necessary in order for communication to ensue. Thus, Latin retained usage well after the rest of it had evolved into other languages. Another example would be Homeric Greek, which retained many features lost in Attic, Doric, Koine, and other dialects, as it was used in only a certain environment and was therefore resistant to change. This has all been studied before better than I can sum it up here. But the point I am making is that analogues can be clearly drawn here, and some interesting theories regarding language become apparent only when seen in this light.

A good example, also covered, would be exploratory processes, as Kirschner and Gerhart call them. These are processes which allow for variation to occur in environments where other variables are forced to change. The example given is the growth of bone length, which requires corresponding muscular, circulatory, and other dependant systems to also change. The exploratory processes allow for future change to occur in the other systems. That is, they expedite plasticity. So, for instance, an ad hoc linguistic example would be the loss of a fixed word order, which would require that morphology step in to fill the gap. In such a case, particles or affixes or the like would have to have already paved the way for case markers to evolve, and would have had to have been present to some extent in the original word order system. (This may not be the best example, but I hope my point comes across.)

Naturally, much of this will have seemed intuitive. But, as Miko stated, these are useful concepts for thinking about evolution; and, in my own case especially, the basics ought to be brought back into scrutiny fairly frequently. Which is justification enough for this post. As always, comments appreciated and accepted. And a possible future post: clade selection as a nonsensical way to approach phylogenic variation.

References:

Caldwell, M. (2002). From fins to limbs to fins: Limb evolution in fossil marine reptiles American Journal of Medical Genetics, 112 (3), 236-249 DOI: 10.1002/ajmg.10773

Gerhart, J., & Kirschner, M. (2007). Colloquium Papers: The theory of facilitated variation Proceedings of the National Academy of Sciences, 104 (suppl_1), 8582-8589 DOI: 10.1073/pnas.0701035104

Mapping Linguistic Phylogeny to Politics

In a recent article covered in NatureNews in Societes Evolve in Steps, Tom Currie of UCL, and others, like Russell Gray of Auckland, use quantitative analysis of the Polynesian language group to plot socioanthropological movement and power hierarchies in Polynesia. This is based off of previous work, available here, which I saw presented at the Language as an Evolutionary Systemconference last July. The article claims that the means of change for political complexity can be determined using linguistic evidence in Polynesia, along with various migration theories and archaeological evidence.

I have my doubts.

Note: Most of the content in this post is refuted wonderfully in the comment section by one of the original authors of the paper. I highly recommend reading the comments, if you’re going to read this at all – that’s where the real meat lies. I’m keeping this post up, finally, because it’s good to make mistakes and learn from them. -Richard

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I had posted this already on the Edinburgh Language Society blog. I’ve edited it a bit for this blog. I should also state that this is my inaugural post on Replicated Typo; thanks to Wintz’ invitation, I’ll be posting here every now and again. It’s good to be here. Thanks for reading – and thanks for pointing out errors, problems, corrections, and commenting, if you do. Research blogging is relatively new to me, and I relish this unexpected chance to hone my skills and learn from my mistakes. (Who am I, anyway?) But without further ado:

I have my doubts. The talk that was given by Russell Gray suggested that there were still various theories about the migratory patterns of the Polynesians – in particular, where they started from. What his work did was to use massive supercomputers to narrow down all of the possibilities, by using lexicons and charting their similarities. The most probable were then recorded, and their statistical probability indicated what was probably the course of action. This, however, is where the ability for guessing ends. Remember, this is massive quantificational statistics. If one has a 70% probability chance of one language being the root of another, that isn’t to say that that language is the root, much less that the organisation of one determines the organisation of another. But statistics are normally unassailable – I only bring up this disclaimer because there isn’t always clear mapping between language usage and migration.

Continue reading “Mapping Linguistic Phylogeny to Politics”