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Signs of Change: Regional and Generational Variants in British Sign Language

British Sign Language chart

British Sign Language chart

As societies change,so too do its languages. In the English-speaking world, we often make note ofchanges in language by recognizing the rise of new words, like “selfie,” and the repurposing of familiar words, such as “because.” It may not be a surprise, then, to learn that this “evolution” isn’t limited to the spoken word: sign languages can also change over time. In a recent PLOS ONE study, scientists examined regional variations within British Sign Language (BSL), and found evidence that the language is evolving and moving away from regional variation.

To assist in this undertaking, the authors used data collected and recorded for the British Sign Language Corpus Project. About 250 participants took part in the project, recruited from eight regions in the UK. In addition to hailing from different parts of the country, participants came from various social, familial, and educational backgrounds.

When the first deaf schools were established across the UK in 1760, there was little standardization in signing conventions. Consequently, depending on the school you were attending, schools sometimes taughtpupils to use different signs to convey the same concepts or words. The authors posit that this lack of standardization may be the basis for today’s regionalism in BSL.

The participants were given visual stimuli, such as colors or numbers, and then asked to provide the corresponding sign, one that they would normally use in conversation. The researchers also recorded participants engaging in unscripted conversations, a more formal interview, and in the delivery of a personal narrative,all of which were incorporated into the authors’ study and analyzed.

Example of the stimuli shown to participants.

Example of the stimuli shown to participants.

In their analysis, researchers focused on four concepts: UK place names, numbers, colors, and countries. The participants’ responses to the visual stimuli were compared to with their recorded conversation to control for any confounding variables, or unforeseen social pressure to sign in a particular way. The responses were also coded as being either “traditional” or “non-traditional” according to the regional signing conventions.

Results indicated that age may play a role in whether a participant uses traditional or non-traditional signs.Particularly when signing for countries, about half the responses given by younger participants were non-traditional signs. In addition, some participants—young and old—explained that they changed the country sign they used as they grew older. The researchers posit that this may be due to changing definitions of political correctness, in which older, more traditional signs are now perceived to be politically incorrect.

The authors also found that age may also play an important role in the participant’s use of color and number signs. As was the case for signing countries, younger participants were more likely to use non-traditional signs, and older participants more likely to use traditional signs. The researchers noted that younger participants using signs non-traditional to their region seemed to be adopting signing conventions from southern parts of the country, such as London, or from multiple regions. In other cases, younger participants responded by signing the first letter of the word, such as ‘p’ for purple. The authors attribute this generational shift to the participants’ increased exposure to different signing conventions, ushered in by technological developments, such as the Internet, and increased opportunities for travel.

Changing social norms, technologies, and opportunities—these are no strangers to us by now. As the world changes, so too do the ways in which we communicate, verbally and physically.


Citation:Stamp R, Schembri A, Fenlon J, Rentelis R, Woll B, et al. (2014) Lexical Variation and Change in British Sign Language. PLoS ONE 9(4): e94053. doi:10.1371/journal.pone.0094053

Image 1: British Sign Language chart by Cowplopmorris, Wikimedia Commons

Image 2: Figure 3 from article

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Plant Roots May Lie Beneath Namibian Fairy Circles

fairy3Circles of barren land, ranging from one to several feet in diameter, appear and disappear spontaneously in Namibian grasslands. The origins of these ‘fairy circles’ remain obscure, and have been attributed to causes ranging from the fantastic (the poisonous breath of a subterranean dragon) to those backed by more evidence, such as the work of a soil termite. A recent PLOS ONE paper suggests another possibility: Patterns that emerge during normal plant growth. Author Michael Cramer elaborates on the results of this study:

How did you become interested in studying the Namibian fairy circles, and are similar circles seen elsewhere?

It would be hard not to be intrigued by these mysterious barren circles on the edge of the spectacular Namibian sand sea! These circles are also reminiscent of soil mounds in other places, for example mima mounds in the US, “heuweltjies” in South Africa and “campos de murundus” in South America that have primarily been ascribed to faunal activity. Like fairy circles, these mounds may, however, represent a distinct product of patterns formed by vegetation. My co-author, Nichole Barger, became intrigued by both these phenomena while I was on sabbatical in her lab.

Many other scientific ideas have been proposed to explain the occurrence of these circles. What’s missing from these explanations? 

Any explanation of fairy circles has to provide a plausible mechanism for regular spacing of these relatively large circles in the landscape. The most common explanation to date has been that termites cause the circles. While it is undoubtedly true that ants, termites and other fauna do occur in the circles and may play a role in maintenance of the circles, we suggest that inter-plant competition is the primary cause that drives circle formation. This places plant competition in focus as a possible mechanism for determining the shape, size and distribution of the circles.

What made you think the patterns could be formed by plant growth patterns themselves?

We stood on the shoulders of giants! Previous studies have alluded to vegetation patterning as a possible cause.  Other researchers have also produced computer models to predict fairy circle occurrence and found plant growth may play a role.  More generally, understanding of spatial patterns formed by plants and the realization that this emergent phenomenon is common in arid landscapes has increased recently. Several groups have produced mathematical models that explain the production of vegetation patterns (gaps, bands and spots) and show that increasing aridity can result in transition from one pattern to another.

fairy2How did you analyze the fairy circles?

We adopted two approaches. We used Google Earth to obtain images of sites across Namibia, analyzed these to determine circle morphological characteristics, and  then combined the images with environmental data to predict the distribution of fairy circles. We performed ground surveys to measure circle morphology and collect soil samples. Soils were sampled at various depths and regular intervals inside and outside the circles and analyzed for water and nutrient contents.

What did you find?

We found that we could predict, with 95% accuracy, the distribution of fairy circles based on just three variables. Rainfall strongly determined their distribution, and differences in rainfall from year to year may thus explain why circles dynamically appear and disappear in this landscape.  The patterns of moisture depletion across the circles are also consistent with plant roots foraging for water in the circle-soil. The size and density of the circles is inversely related to resource availability, indicating that bigger circles occur in drier areas and where soil nitrogen is lower.

Do the data in this study strengthen previous results or disprove any older explanations for the circles?

Our results corroborate previous results and extend them, but we have interpreted the results in a novel manner. Since our study was correlative, i.e: we correlated the occurrence of fairy circles with certain environmental conditions, it does not disprove existing hypotheses. Direct experiments that result in fairy circles being created or closing up are perhaps the only way  to prove or disprove any of these ideas.

fairy1Do these results have implications for other ecosystems? For example, could similar ecological conditions cause fairy circles to form in other grasslands around the world?

Circular grass rings do occur in many contexts. For example, Stipagrostis ciliata in the Negev and Muhlenbergia torreyi (ring muhly) in the US (e.g. New Mexico, Utah) form rings. The distinction is that these are much smaller (ca. < 1 – 2 m diameter) and less regularly spaced than fairy circles. Nevertheless, their origins may have some commonalities with fairy circles. The special circumstance that results in the spectacular Namibian fairy circles may be the fact that the soils are very sandy and homogenous.

More generally, the fairy circles represent an example of how patterns formed by growing plants can create heterogenous spaces in otherwise homogenous grassland. Differences in soil moisture or composition across the span of a fairy circle can provide habitat for both grasses and fauna that would otherwise not thrive in this arid environment.


Citation: Cramer MD, Barger NN (2013) Are Namibian “Fairy Circles” the Consequence of Self-Organizing Spatial Vegetation Patterning? PLoS ONE 8(8): e70876. doi:10.1371/journal.pone.0070876

Images: fairy circles by Vernon Swanepoel (top); images below from 10.1371/journal.pone.0070876