tag:theconversation.com,2011:/global/topics/neolithic-revolution-2913/articlesNeolithic revolution – The Conversation2015-11-11T05:04:21Ztag:theconversation.com,2011:article/503192015-11-11T05:04:21Z2015-11-11T05:04:21ZWhy we think the very first farmers were small groups with property rights<figure><img src="https://images.theconversation.com/files/101098/original/image-20151106-16239-qaghwj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A neolithic farm in Scotland that may be the oldest in northern Europe.
</span> <span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Neolithic_Revolution#/media/File:Knapp_of_Howar_2.jpg">Drewcorser/wikimedia</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>For 95% of the history of modern humans we were exclusively hunter gatherers. Then suddenly about 12,000 years ago, something happened that revolutionised the way humans lived and enabled the complex societies we have today: farming. </p>
<p>But what triggered this revolution? Understanding this is incredibly challenging – because this occurred so far in the past, there are many factors to consider. However, by <a href="https://simulatingcomplexity.wordpress.com/2015/09/01/the-hypes-and-downs-of-simulation/">simulating the past</a> using a complex computational model, <a href="http://www.pnas.org/content/early/2015/10/28/1511870112.abstract">we found</a> that the switch from foraging to farming most likely began with very small groups of people that were using the concept of property rights.</p>
<h2>Farming: an unlikely choice</h2>
<p>It may seem obvious why we switched from foraging to farming: it made it possible to stay in one place, feed larger populations, have greater food security and build increasingly complex societies, political structures, economies and technologies. However, these advantages took time to develop and our early farmer ancestors would not have seen these coming. </p>
<p>Indeed, archaeological research suggests that when farming began it was <a href="http://www.nature.com/nature/journal/v418/n6898/abs/nature01019.html">not a particularly attractive lifestyle</a>. It involved more work, a decrease in the quality of nutrition and health, an increase in disease and infection, and greater challenges in defending resources. For a hunter-gatherer at the cusp of the “agricultural revolution”, a switch to farming wasn’t the obvious choice. </p>
<p>So why then did early farmers choose this lifestyle? We know that farming started around the beginning of the <a href="http://www.ucmp.berkeley.edu/quaternary/holocene.php">Holocene</a>, the unusually warm and stable climate phase we find ourselves in today. This <a href="http://www.jstor.org/stable/1154126?seq=1#page_scan_tab_contents">may have lead to changes</a> in population sizes, mobility and resource quality and predictability – and in turn changes to social organisation. We decided to examine the issue using a new method to analyze a computational model on the origins of our farming past. </p>
<p>A couple of years ago, <a href="http://www.pnas.org/content/110/22/8830.abstract">a well-regarded model</a> of the origins of agriculture considered a population of people divided into groups who first gained food by foraging or farming, and then either tried to share or steal each other’s food. Whether they decided to share or steal was determined by their behavioural strategy: sharer, civic or bourgeois. Sharers always share, of course; civics are sharer-enforcers – where they will punish someone who tries to not share; and if the agent is a bourgeois then they will never try to steal farmed food, so they could be considered as having farming-friendly property rights.</p>
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<img alt="" src="https://images.theconversation.com/files/101240/original/image-20151109-7521-pzrf77.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/101240/original/image-20151109-7521-pzrf77.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/101240/original/image-20151109-7521-pzrf77.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/101240/original/image-20151109-7521-pzrf77.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/101240/original/image-20151109-7521-pzrf77.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/101240/original/image-20151109-7521-pzrf77.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/101240/original/image-20151109-7521-pzrf77.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Plough Horn used in agriculture about 4800-3000BC in Eastern Europe.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:CucuteniAgriculture.JPG">CristianChirita/wikimedia</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
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<p>According to the model, the agents occasionally changed their behaviour and also sometimes migrated to a different group. For each cycle the amount of food gained from farming changed according to climate volatility, which was estimated using <a href="http://www.gfy.ku.dk/%7Ewww-glac/ngrip/index_eng.htm">ice core data</a> given in intervals of 20 years. </p>
<p>These simulations showed that farming and farming-friendly property rights evolved together around the same time as farming is observed in the archaeological record. However, it included many factors (parameters) other than property rights that may have influenced the emergence of farming.</p>
<h2>Millions of possibilities</h2>
<p>In our study we explored the effects of other parameters in more detail. Knowing values for parameters that shaped something that occurred so long ago is very difficult. For example, how can you know what proportion of ancient people migrated from group to group in each generation? You may find in ethnographic or archaeological data (if you are very lucky) that this is approximately a fifth of the population at a certain time. But what if it was a sixth? Would this lead to a different outcome? </p>
<p>And what about the simultaneous effects of another parameter, for example the amount of food gained by foraging, for which you don’t know the exact value either. You would need to check all the different combinations of reasonable values for these two parameters on the outcome of the model. This is complicated enough, but at least you can visualise the results. Now try adding a third unknown parameter – or ten. Things can get very complicated very quickly.</p>
<p>We implemented a method that explores the effects of 11 parameters: the number of groups; the migration rate; the amount of behavioural experimentation; the cost of a conflict within the group; the cost and probability of a conflict between groups; the foraging productivity; the intensities of farming and foraging property rights; the amount of farming investment; and the level of conformism. This method randomly picked 12m different combinations of these parameter values from realistic ranges. We then ran the model for each of these combinations and asked how “good” the result found was; this was defined as how many of the people in the model were farmers by 9,000 years ago (when farming became established). </p>
<p>We then looked back at the combinations of parameters that made these “good” results. From our results we could predict that for farming to develop it would have been beneficial for groups to be small, around four to six people, and that property rights were indeed an important factor. We also found that it is possible for farming to have begun even if the amount of food gained by farming was less than that of foraging.</p>
<p>Statistician George Box once said that “<a href="http://www.tandfonline.com/doi/abs/10.1080/01621459.1976.10480949">all models are wrong</a>”. But when we try to understand processes that are shaped by many factors our intuitions will usually fail us. All models maybe wrong, but they can guide and sharpen those intuitions.</p><img src="https://counter.theconversation.com/content/50319/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Elizabeth Gallagher receives funding from the Engineering and Physical Sciences Research Council (EPSRC) . </span></em></p>Switching from foraging to farming would not have been an obvious choice for our ancestors. But they seem to have done it nonetheless.Elizabeth Gallagher, PhD student mathematical biology, UCLLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/462172015-08-17T20:04:40Z2015-08-17T20:04:40ZMass grave reveals organised violence among Europe’s first farmers<figure><img src="https://images.theconversation.com/files/92162/original/image-20150817-5121-1gt41tw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The owner of this skull had a nasty run in with an axe.</span> <span class="attribution"><a class="source" href="http://www.pnas.org/cgi/doi/10.1073/pnas.1504365112">Christian Meyer</a></span></figcaption></figure><p>The discovery of 26 bodies with lethal injuries in a 7,000 year old mass grave in Germany provides more evidence of organised large-scale violence in Neolithic Europe. The findings, reported in <a href="http://www.pnas.org/cgi/doi/10.1073/pnas.1504365112">the journal PNAS</a>, also help us understand the sudden and perhaps brutal ending of central Europe’s first farming culture.</p>
<p>The Linear Pottery (<em>Linienbandkeramik</em>, or LBK) culture which dominated central Europe between 5600 and 4900 BC was once depicted as peaceful and pioneering – farmers who cleared land and carved new communities out of the heavily-forested “wilderness”.</p>
<p>This view began to crumble with the discovery in the late 1980s of a <a href="http://oxfordindex.oup.com/view/10.1093/acprof:osobl/9780199573066.003.0005">mass grave at Talheim</a> in southern Germany, containing the remains of 34 men, women and children, many of whom showed evidence of lethal injuries caused by stone axes. </p>
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<a href="https://images.theconversation.com/files/92133/original/image-20150817-5110-ypu877.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/92133/original/image-20150817-5110-ypu877.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/92133/original/image-20150817-5110-ypu877.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=514&fit=crop&dpr=1 600w, https://images.theconversation.com/files/92133/original/image-20150817-5110-ypu877.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=514&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/92133/original/image-20150817-5110-ypu877.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=514&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/92133/original/image-20150817-5110-ypu877.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=646&fit=crop&dpr=1 754w, https://images.theconversation.com/files/92133/original/image-20150817-5110-ypu877.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=646&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/92133/original/image-20150817-5110-ypu877.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=646&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Linear Pottery (yellow and bright green) dominated much of Neolithic Europe.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:European-middle-neolithic-en.svg">Joostik</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
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<p>This was followed not long after by the findings from an enclosure (a precursor to fortified Roman army camps) at <a href="http://www.inrap.fr/preventive-archaeology/Events/The-archaeology-of-violence-wartime-violence-mass-violence/p-19065-lg1-Conference-Maria-Teschler-Nicola.htm">Asparn/Schletz</a> in Austria. Here, the remains of 67 people were found lying in haphazard positions in the bottom of just one section of the enclosure ditch, the implication being that many more individuals are represented across the site as a whole. It is clear that they too died violently, with many skulls showing signs of multiple blows. </p>
<p>That fact both of these massacres – no other word can be applied – fell near the end of the Linear Pottery culture, around 5000 BC, raised the possibility that things ended less than peacefully.</p>
<h2>Third massacre</h2>
<p>In the <a href="http://www.pnas.org/cgi/doi/10.1073/pnas.1504365112">latest paper</a>, a German team led by Christian Meyer present the recently discovered third instalment in this story. A long trench at the site of Schöneck-Kilianstädten, central Germany, held the remains of at least 26 individuals, found commingled in a mass grave, again with evidence of multiple injuries showing no signs of healing. Most were caused by stone axes, but there were also arrowhead wounds. This was almost certainly a single event, again dating to around 5000 BC. </p>
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<span class="caption">A section of the mass grave.</span>
<span class="attribution"><a class="source" href="http://www.eurekalert.org/jrnls/pnas/15-04365.htm">Meyer et al / PNAS</a></span>
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<p>Intriguingly, as at Asparn/Schletz, the graves contained no children aged 9-16 or young women. This suggests the capture of children and young women may have been one of the motivations for conflict, as it has been in more recently recorded societies around the world.</p>
<p>These events were devastating not only to those involved, but to the entire society. While we have only the vaguest idea of the total population of Neolithic Europe at any particular point, we do have some sense of the size of local villages – usually around 50 to 100 inhabitants. Thus, the deaths of even 26 or 34 people represents an event that, scaled up for an appropriate comparison with modern population levels, would entail killing on a scale seen today only in the most war-torn countries.</p>
<h2>Cycle of conflict</h2>
<p>Archaeology deals with fragments of the past, and there is always the possibility of bias in what survives and what does not, as well as in what is found and what remains hidden. Add to this the fact that radio-carbon estimates provide a date range rather than a specific year and the discovery of one massacre falling at approximately the same time as the disappearance of Linear Pottery may be no more than a coincidence. </p>
<p>The finding of a second example begins to suggest a pattern, however tentatively. The discovery of a third case looks very suspicious indeed. The question that naturally arises is why this particular point in time should see such a widespread outbreak of conflict, involving the killing of what could easily be the entire populations of small hamlets.</p>
<p>While there is certainly evidence of conflict both before (including among the hunter-gatherers that preceded the Neolithic) and after 5000 BC, this usually takes the form of isolated incidents involving relatively few individuals. These mass graves were the result of something larger and more organised.</p>
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<a href="https://images.theconversation.com/files/92136/original/image-20150817-5121-1i7p5d7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/92136/original/image-20150817-5121-1i7p5d7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/92136/original/image-20150817-5121-1i7p5d7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=362&fit=crop&dpr=1 600w, https://images.theconversation.com/files/92136/original/image-20150817-5121-1i7p5d7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=362&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/92136/original/image-20150817-5121-1i7p5d7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=362&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/92136/original/image-20150817-5121-1i7p5d7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=454&fit=crop&dpr=1 754w, https://images.theconversation.com/files/92136/original/image-20150817-5121-1i7p5d7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=454&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/92136/original/image-20150817-5121-1i7p5d7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=454&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">This child’s skull was found with a large fracture.</span>
<span class="attribution"><span class="source">Christian Meyer</span></span>
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<p>One theory <a href="http://www.sciencedirect.com/science/article/pii/S0305440313001052">blames the environment</a>. A period of climatic instability led to increased competition for resources and eventually to conflict – including the extermination of some entire communities. This interpretation very much divides the room. Many researchers take exception to what they see as an overly simplistic, environmentally deterministic explanation, and favour <a href="http://www.sciencedirect.com/science/article/pii/S0305440314002982">internal causes</a> for conflict. Other strategies could have been employed to cope with shortages, emphasising greater cooperation rather than competition. </p>
<p>There is also the problem of precisely correlating climatic records and archaeological events. While there is some evidence of a climatic downturn at the end of the 6th millennium BC, there is still considerable leeway in the dating of both this downturn, and in the massacres discussed here, making it very difficult to link them in a causal way.</p>
<p>The findings at Schöneck-Kilianstädten will no doubt fuel this debate, and rightly so, since it is an important one that is not without implications for our own future. Some studies have suggested that global warming is likely to lead to a massive <a href="http://www.sciencemag.org/content/341/6151/1235367.abstract">increase in levels of conflict</a> worldwide. If such a link does turn out to have been the case in Neolithic Europe, it would be depressing if we have not learned anything in the intervening millennia that would enable us to avoid a similar fate.</p><img src="https://counter.theconversation.com/content/46217/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Rick Schulting does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>These massacres entail killing on a relative scale seen today only in the most war-torn countries.Rick Schulting, Lecturer in Scientific and Prehistoric Archaeology, University of OxfordLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/387252015-04-20T20:03:50Z2015-04-20T20:03:50ZThere was a decline of male diversity when humans took to agriculture<figure><img src="https://images.theconversation.com/files/78187/original/image-20150416-5631-h3k0kv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The move to cultivating the land for food has dramatic impact on the male population.</span> <span class="attribution"><span class="source">Shutterstock/hiroshi teshigawara </span></span></figcaption></figure><p>When people abandoned a hunter-gatherer lifestyle and became agriculturalists, initially some 10,000 years ago, they gave up a lot of things.</p>
<p>This significant shift in the way they obtained their food was probably not something they elected to do. Instead, population pressure and diminishing resources forced people into developing new intensified forms of subsistence. This meant people became more sedentary. </p>
<p>Not only did these new arrangements result in the emergence of new social structures and new technological innovations, but it also had some very negative outcomes.</p>
<p>As people intensified their subsistence strategies and became sedentary there was an increase in population size.</p>
<p>New diseases evolved through the closer association with animals and coupled with large population sizes this enabled the emergence of epidemic scale disease patterns. This list probably included diseases such as measles, influenza, whooping cough, smallpox and tuberculosis.</p>
<p>A lot happened when humanity turned to agriculture.</p>
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<a href="https://images.theconversation.com/files/75637/original/image-20150323-26701-e6htje.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/75637/original/image-20150323-26701-e6htje.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/75637/original/image-20150323-26701-e6htje.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/75637/original/image-20150323-26701-e6htje.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/75637/original/image-20150323-26701-e6htje.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/75637/original/image-20150323-26701-e6htje.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/75637/original/image-20150323-26701-e6htje.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/75637/original/image-20150323-26701-e6htje.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Excavation of 10,500 year old mud brick house, providing some of the earliest evidence for village life associated with agriculture, Boncuklu, Turkey.</span>
<span class="attribution"><a class="source" href="http://boncuklu.org/">Dr Andrew Fairburn</a>, <span class="license">Author provided</span></span>
</figcaption>
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<h2>The genome tells the story</h2>
<p>We were involved in a study, <a href="http://genome.cshlp.org/content/early/2015/03/13/gr.186684.114.abstract">published recently</a>, which looked at specific parts of modern genomes of people from around the globe. It also appears that there were significant changes in population structure as well, and not just population size.</p>
<p>The study focused on the Y chromosome that is only inherited through the paternal line from fathers to sons. This tells us about origins and migrations of males in the population, but it can also reveal patterns in population changes. </p>
<p>These results were compared to those from the mitochondrial DNA, that is the DNA inherited through the maternal line in humans.</p>
<p>This provided a very different picture of the regional male and female effective population size. In general terms, the effective population size is the number of individuals in a population who contribute offspring to the next generation.</p>
<p>So the study suggests that there was a global collapse in genetic diversity of the males in contrast to that of females. Essentially this means there was an extreme reduction in the number of males who reproduced, but not a reduction in the number of females.</p>
<p>This appears to correlate with the timing of this major shift in subsistence, referred to by archaeologists as the <a href="http://ancienthistory.about.com/od/artarchaeologyarchitect/g/neolithic.htm">Neolithic.</a></p>
<p>In fact, Y chromosome genetic data suggests this reduction at around 8,000 to 4,000 years ago. Essentially there was a genetic bottleneck in male genetic diversity at that time which cannot be easily explained through natural selection. </p>
<h2>So what happened?</h2>
<p>Could the development of agriculture and a shift in social patterns explain this change?</p>
<p>If male reproductive success was being controlled by a smaller number of males of high social order, for example a smaller ruling elite, then we would see a situation where male population (genetic) diversity was reduced.</p>
<p>An example of such an event from much later times is <a href="http://www.history.com/topics/genghis-khan">Genghis Khan</a>. He was reputed to have sired hundreds of children, resulting in millions of Asian men today who bear a <a href="http://news.nationalgeographic.com.au/news/2003/02/0214_030214_genghis.html">very similar Y chromosome lineage</a>. Identifying such social changes within the archaeological record, however, is easier said than done.</p>
<p>The Neolithic introduced a new system of economic production and increased social stratification. The rise of a social elite and followers and the development of hierarchies in a society, independently emerged in several global regions, and later spread across much of the world. </p>
<p>The studied 110 populations were grouped according to seven global regions and the decrease of male genetic diversity emerges in all of them (with the exception of Siberia).</p>
<p>It is important to note that the Neolithic took many different forms as it spread across the globe. It was not a prehistoric corporate global takeover, but it did set humanity on a course that it could not turn back from. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/75630/original/image-20150323-26691-j3s01q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/75630/original/image-20150323-26691-j3s01q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=402&fit=crop&dpr=1 600w, https://images.theconversation.com/files/75630/original/image-20150323-26691-j3s01q.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=402&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/75630/original/image-20150323-26691-j3s01q.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=402&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/75630/original/image-20150323-26691-j3s01q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=505&fit=crop&dpr=1 754w, https://images.theconversation.com/files/75630/original/image-20150323-26691-j3s01q.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=505&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/75630/original/image-20150323-26691-j3s01q.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=505&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">An early burial from the archaeological site of Caleta Vitor, Chile. Agriculture mixed with a marine economy provided the basis for village life at this 7,000 year old site.</span>
<span class="attribution"><span class="source">Chris Carter, ANU</span></span>
</figcaption>
</figure>
<h2>Unravelling the history</h2>
<p>Archaeology can be very effective for reconstructing past social change in societies, ranging from the study of artefacts which may reveal new innovations to the changing frequencies in trauma and disease patterns in skeletons.</p>
<p>It can reveal the development of new forms of structures, such as fortifications, irrigation systems and enlarged settlements. It can also show the impact of people on their environments such as domestication of plants and animals, and the deforestation and increased salinisation of landscapes. </p>
<p>But competition through male-driven conquest represents a signature that archaeologists would find exceedingly difficult to identify from the material archaeological record alone.</p>
<p>Studies looking at ancient genomes are starting to detect patterns in population change that would otherwise remain hidden if we relied solely on standard archaeological investigations. </p>
<p>Research into genetic changes in populations therefore can serve as a catalyst for archaeologists to revisit the material record with such hypotheses in mind.</p>
<p>The opportunity now exists to test the global hypothesis proposed by this study from modern and ancient genomes. By working much more closely with archaeologists and palaeo-environmental scientists we can reconstruct the social and environmental contexts that may have driven changes in ancient populations.</p>
<p>The techniques now exist to build far more sophisticated models for understanding the global past of humanity through targeting specific geographic regions. It will be of great interest to develop a clearer understanding of past societies that did not endure the many hardships of agriculture. Aboriginal Australia is one such place.</p>
<p>Modern and ancient genomics is playing the key role in generating this revision of our shared past. Approaches that identify culturally driven sex-specific changes in our ancient human history provide yet another insight into the impact of the world changing Neolithic revolution.</p><img src="https://counter.theconversation.com/content/38725/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Michael Westaway receives funding from the Australian Research Council and Griffith University.</span></em></p><p class="fine-print"><em><span>David Lambert receives funding from the Australian Research Council and Human Frontier Science.</span></em></p><p class="fine-print"><em><span>Monika Karmin receives funding from EU European Regional Development Fund and Estonian Research Council.</span></em></p>The change of lifestyle from 10,000 years ago had a dramatic impact on the male divefrsity revealed in DNA.Michael Westaway, Senior Research Fellow, Environmental Futures Research Institute, Griffith UniversityDavid Lambert, Dean Research Griffith Sciences and Professor of Evolutionary Biology, Griffith UniversityMonika Karmin, Researcher in Evolutionary BiologyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/301882014-08-06T13:57:55Z2014-08-06T13:57:55ZFarming left us better fed but not necessarily better led – how despots arose with agriculture<figure><img src="https://images.theconversation.com/files/55865/original/247s7kd4-1407321635.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Give a man a ploughshare, and he'll turn it into a sword.</span> <span class="attribution"><a class="source" href="http://commons.wikimedia.org/wiki/File:Maler_der_Grabkammer_des_Sennudem_001.jpg">Zenodot Verlagsgesellschaft mbH</a></span></figcaption></figure><p>For hundreds of thousands of years humans lived in hunter-gatherer societies, eating wild plants and animals. Inequality in these groups is thought to have been very low, with evidence suggesting food and other resources were shared equally between all individuals. In fact, in the <a href="http://hunter-gatherers.org/introd.html">hunter-gatherer societies</a> that still exist today we see that all individuals have a say in group decision making. Although some individuals may act as leaders in the sense of guiding discussions, they cannot force others to follow them.</p>
<p>But it seems that with the beginning of agriculture around 10,000 years ago, this changed. An elite class began to monopolise resources and were able to command the labour of others to do things, such as build monuments in their honour. So how was it that egalitarian societies, where all men were equal, transitioned into hierarchical societies where despots reigned?</p>
<p>In recent years archaeologists have tended to focus on the means by which would-be leaders could coerce other individuals into following them (so-called <a href="http://www.slideshare.net/MohamedLaidSakhri/agency-theory-in-archaeologypresentation">theories of agency</a>). But while leaders probably did coerce their followers once they were in power, it is difficult to see how they could do so at the outset. After all, if all individuals started out with equal resources and equal status, how could one individual force 30 others to do their bidding? This problem forces us to examine the benefits that would-be leaders could provide to their followers – and this is where agriculture comes in.</p>
<p>While hunting wild game did not involve much co-ordination beyond placing traps and positioning hunters, agriculture presented an opportunity to massively increase the amount of food that could be produced. A classic example is the development of irrigation systems, which allowed crops to be grown further away from rivers and water sources. Although the role of irrigation systems in creating despotic states has been <a href="http://www.britannica.com/EBchecked/topic/278180/hydraulic-civilization">overstated in the past</a>, they certainly would have created an opportunity for would-be leaders to behave entrepreneurially by managing their construction. Those that chose to follow their agricultural-technologist leader would then benefit from access to irrigation. This would provide the benefit of increased food production, enhancing both their quality of life and the number of surviving offspring they could produce.</p>
<p>In this way, social hierarchy could initially arise voluntarily – because individuals that chose to follow the leader were materially better off than those that did not. But under what conditions does this voluntary leadership, where everybody benefits, turn into despotism? I tried to answer this question with <a href="http://rspb.royalsocietypublishing.org/content/281/1791/20141349">a new computational model</a>, which has highlighted two key linked factors.</p>
<p>The first is population growth. When populations are small it’s relatively easy for individuals to go back to a leaderless way of life, for example by moving to a new patch of land. This seems to happen in modern hunter-gatherer groups, where people may simply <a href="http://www.jstor.org/stable/2743665">walk away from a bullying leader</a> in the middle of the night. But as population density increases, it becomes harder and harder to find free land to move to that is not controlled by the leader and their followers. Model simulations demonstrate that positive feedback between leaders increasing resource production and population growth can create an obligatory hierarchy, destroying the viability of leaderless life in the area. And empirically, hierarchy formation most often co-occurs with an increase in food production that drives <a href="http://www.psu.edu/dept/liberalarts/sites/kennett/djkennett/pdf/Kennett_Winterhalder2008_Demographic_expansion_despotism_colonisation_East_South_Polynesia.pdf">population growth</a>. </p>
<p>The second factor is the cost of changing the leader. Even if individuals are locked into a hierarchy, despotism is not inevitable if individuals can readily choose to follow a different leader. For example, by moving to a different group with a different leader. Group membership in hunter-gatherer societies is quite fluid, so this is relatively easy. But with agriculture, individuals would have become tied to a plot of land in which they had invested, making leaving the group very costly. This would become even more extreme with irrigation farming, where farmers would be tied to the system. Indeed, the most despotic early states arose in locations such as <a href="http://www.anciv.info/ancient-egypt/society-and-social-hierarchy-in-acient-egypt.html">Egypt</a>, where agriculture had to happen in a narrow valley along the Nile, making dispersal very difficult.</p>
<p>So the use of agriculture established human societies and provided for them in some ways that improved over hunter-gathering. But it shattered the social norm and facilitated the rise of despotism by attracting followers to entrepreneurial leaders that could provide them with benefits, by increasing population density which reduced the ability for others to survive outside the hierarchical group and by making it so costly to leave the group that to do so was unattractive even when faced with despotic leaders. Even in ancient times at the dawn of agriculture there was, it seems, no such thing as a free lunch.</p><img src="https://counter.theconversation.com/content/30188/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Simon Powers receives funding from Swiss NSF grant PP00P3-123344.</span></em></p>For hundreds of thousands of years humans lived in hunter-gatherer societies, eating wild plants and animals. Inequality in these groups is thought to have been very low, with evidence suggesting food…Simon Powers, Post-doctoral Researcher, Université de LausanneLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/49282012-05-06T20:49:02Z2012-05-06T20:49:02ZEverything you need to know about coeliac disease (and whether you really have it)<figure><img src="https://images.theconversation.com/files/10100/original/t33f2bp8-1335761395.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Thinking of jumping on the gluten-free bandwagon? Better think again.</span> <span class="attribution"><span class="source">GlutenFreeChops/Flickr</span></span></figcaption></figure><p>The <a href="http://history-world.org/neolithic.htm">Neolithic Revolution</a> introduced a whole range of new foods and proteins into the human digestive tract. But this phenomenal change created the perfect conditions for the rise of coeliac disease. </p>
<p>While most proteins were readily consumed, some people’s immune systems struggled to tolerate others. Wheat was the first cereal to be widely domesticated, and in the case of the gluten protein from wheat, the result of this struggle was coeliac disease. </p>
<p>When people with coeliac disease consume gluten, an abnormal immune reaction occurs causing inflammation and damage to the small bowel lining. This impairs absorption of nutrients and can lead to a wide range of symptoms and medical complications.</p>
<h2>Ancient condition, 20th century treatment</h2>
<p>The second century Greek physician Arateus is credited with coining the term coeliac disease, or “koiliakos”, after the Greek word koelia (abdomen), to describe patients suffering typical symptoms of diarrhoea, weight loss and anaemia. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/10092/original/nw4mrfhq-1335759356.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/10092/original/nw4mrfhq-1335759356.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/10092/original/nw4mrfhq-1335759356.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/10092/original/nw4mrfhq-1335759356.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/10092/original/nw4mrfhq-1335759356.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/10092/original/nw4mrfhq-1335759356.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/10092/original/nw4mrfhq-1335759356.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Wheat was finally identified as the culprit of the reoccurring health problems.</span>
<span class="attribution"><span class="source">Joana Hard</span></span>
</figcaption>
</figure>
<p>Reports from the 19th and 20th century reveal considerable suffering and mortality associated with coeliac disease, particularly in infants. An effective treatment didn’t arise until the middle of the 20th century, when gluten was identified as the culprit. </p>
<p>The discovery was fortuitous – a wartime bread shortage led Dutch paediatrician Willem Dicke to observe improved health in children with coeliac disease, and note their relapse shortly after food drops of bread returned wheat back into their diet. </p>
<p>The work of Australian physician Charlotte Anderson established it was the gluten component of wheat (and also rye, barley and oats) that caused coeliac disease. It was the 1950s and the age of treatment with a gluten-free diet had begun.</p>
<h2>Prevalence and the reasons why</h2>
<p>Far from being a medical rarity, coeliac disease is very common today, affecting more than one in 100 Australians. And in the last half century, it has become approximately <a href="http://www.ncbi.nlm.nih.gov/pubmed/17944736">twice as common every two decades</a>, similar to the rise in other immune diseases, such as type 1 diabetes. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/10093/original/qqhzzm5n-1335759870.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/10093/original/qqhzzm5n-1335759870.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/10093/original/qqhzzm5n-1335759870.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/10093/original/qqhzzm5n-1335759870.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/10093/original/qqhzzm5n-1335759870.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/10093/original/qqhzzm5n-1335759870.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/10093/original/qqhzzm5n-1335759870.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The increased prevalence of the disease may be due to hyper-conscious hygiene practices.</span>
<span class="attribution"><span class="source">sydeen/Flickr</span></span>
</figcaption>
</figure>
<p>Why the prevalence is increasing remains unknown, but a variety of environmental factors and the “<a href="https://theconversation.com/how-clean-is-too-clean-trust-your-gut-instincts-855">hygiene hypothesis</a>” have been proposed. </p>
<p>Today, people are typically diagnosed in adulthood and are mostly female. Alarmingly, <a href="http://www.ncbi.nlm.nih.gov/pubmed/21426277">80% of Australians with coeliac disease remain undiagnosed</a>. This is because symptoms are wide-ranging and largely non-specific. And coeliac disease still remains “off the radar” for many doctors.</p>
<h2>Many symptoms but simple diagnosis</h2>
<p>In people with coeliac disease, gluten causes widespread inflammation not limited to the bowel. Patients are commonly troubled by gut upset (such as bloating, abdominal pain, diarrhoea and/or constipation), lethargy, anaemia, and nutrient deficiencies, such as low iron. They can also suffer loss of fertility, migraine headaches, abnormal liver function, arthritis and autoimmune diseases, such as type 1 diabetes and autoimmune thyroid disease. </p>
<p>Bones are more likely to be thinned out (osteoporosis) and patients can develop certain cancers, such as lymphoma. The good news is that early diagnosis and treatment can greatly reduce the chances of these complications.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/10094/original/w9jpcx6b-1335760316.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/10094/original/w9jpcx6b-1335760316.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=425&fit=crop&dpr=1 600w, https://images.theconversation.com/files/10094/original/w9jpcx6b-1335760316.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=425&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/10094/original/w9jpcx6b-1335760316.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=425&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/10094/original/w9jpcx6b-1335760316.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=533&fit=crop&dpr=1 754w, https://images.theconversation.com/files/10094/original/w9jpcx6b-1335760316.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=533&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/10094/original/w9jpcx6b-1335760316.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=533&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A blood test is a simple way to indicate whether you may have coeliac disease.</span>
<span class="attribution"><span class="source">Healthcare Experts/Flickr</span></span>
</figcaption>
</figure>
<p>A simple blood test is used to screen for coeliac disease, although making a definite diagnosis requires demonstrating the characteristic small bowel changes of flattened and inflamed lining (“villous atrophy”) under the microscope. Small bowel samples are readily obtained by gastroscopy, a ten-minute procedure performed under sedation that introduces a flexible instrument via the mouth into the small bowel to allow samples to be taken. </p>
<p>It’s vital that a gluten-free diet isn’t started before testing for coeliac disease, as this can cause false negative results.</p>
<h2>Genes and the environment</h2>
<p>Coeliac disease shares certain predisposing genes with autoimmune diseases, such as type 1 diabetes (which explains why these conditions often occur together). These genes control how the immune system “recognises” and responds to foreign proteins and are fundamental for disease to develop. </p>
<p>But genes alone are not enough to cause coeliac disease and environmental factors are thought to play an important role in “triggering” disease in those with genetic susceptibility. Some factors appear to increase coeliac disease risk (such as <a href="http://www.ncbi.nlm.nih.gov/pubmed/17032199">rotavirus infection</a> in infancy) while some may reduce the risk. <a href="http://www.ncbi.nlm.nih.gov/pubmed/11976167">Breastfeeding at the time gluten is introduced</a> to an infant, for instance, may protect against developing disease. </p>
<h2>The challenge of gluten-free diets</h2>
<p>Excluding all dietary sources of gluten from wheat, rye, barley and oats allows the small bowel damage to heal and symptoms to resolve – but it’s far from easy. Wheat flour, the most common and significant source of gluten, is found in many foods, such as bread, breakfast cereals, cakes, biscuits, pasta, pastries and pizzas. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/10096/original/r9h3cp6d-1335760638.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/10096/original/r9h3cp6d-1335760638.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/10096/original/r9h3cp6d-1335760638.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/10096/original/r9h3cp6d-1335760638.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/10096/original/r9h3cp6d-1335760638.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/10096/original/r9h3cp6d-1335760638.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/10096/original/r9h3cp6d-1335760638.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">People with coeliac disease have to learn how to pass up the pastries.</span>
<span class="attribution"><span class="source">pastryfusion/Flickr</span></span>
</figcaption>
</figure>
<p>There are also “hidden” sources of gluten found in sauces and processed foods and less obvious items, such as malted foods and beer. While gluten-free alternatives are increasingly available, they’re much more expensive and generally much less palatable – anyone who has ever tried gluten free bread will know how dense and crumbly it is! </p>
<p>Compounding its complexity, cost and poor palatability, the gluten-free diet needs to be very strict to work - even <a href="http://www.ncbi.nlm.nih.gov/pubmed/17209192">small amounts of gluten</a> (about 50 milligrams – less than 1/100th of a slice of bread) can cause bowel damage. </p>
<p>That’s why patients need to be obsessive about excluding gluten – for people with coeliac disease the gluten free diet is not a fad but a serious medical treatment.</p>
<h2>Is gluten free for everyone?</h2>
<p>It’s hard to miss the ever-expanding sections of supermarkets dedicated to selling gluten-free food and many restaurant menus list gluten-free options. The gluten-free food industry is booming, with a global market projected to well exceed US$4 billion over the next three years. </p>
<p>Interestingly, a recent market survey commissioned by <a href="http://www.coeliac.org.au/">Coeliac Australia</a> indicates that approximately 10% of Australians are currently following a strict or significantly reduced gluten diet. This is ten times greater than the total number of Australians thought to have coeliac disease.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/10099/original/qh39m5s9-1335761035.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/10099/original/qh39m5s9-1335761035.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=402&fit=crop&dpr=1 600w, https://images.theconversation.com/files/10099/original/qh39m5s9-1335761035.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=402&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/10099/original/qh39m5s9-1335761035.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=402&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/10099/original/qh39m5s9-1335761035.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=505&fit=crop&dpr=1 754w, https://images.theconversation.com/files/10099/original/qh39m5s9-1335761035.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=505&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/10099/original/qh39m5s9-1335761035.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=505&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A gluten-free diet isn’t all that tasty, and not necessarily the healthiest option.</span>
<span class="attribution"><span class="source">simply..gluten-free/Flickr</span></span>
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</figure>
<p>It’s likely that alternative health practitioners, disease advocacy groups, proliferating internet blogs and forums, and the gluten-free food industry are directly or indirectly fuelling the mounting public perception that a gluten-free diet is intrinsically “healthy” or suitable to treat a variety of symptoms and illnesses. </p>
<p>But medical evidence to support undertaking a strict gluten-free diet outside of coeliac disease is <a href="http://www.ncbi.nlm.nih.gov/pubmed/22237879">minimal</a>. If people do choose to follow a gluten free diet, it’s medically important that coeliac disease is excluded first so that testing isn’t compromised - a missed diagnosis of coeliac disease can be disastrous for long-term health. </p>
<p>While many people feel their symptoms might improve on a gluten-free diet, this doesn’t necessarily mean they have coeliac disease. Nor does it mean a gluten-free diet is the most appropriate treatment for them. </p>
<p>Many cases of perceived wheat or gluten intolerance reported by patients is not due to gluten itself but intolerance to the wheat’s carbohydrate component (fructans). For some, a diet reducing fructans and other fermentable carbohydrates, a <a href="http://www.ncbi.nlm.nih.gov/pubmed/20136989">low FODMAP (fermentable oligo-, di-, mono-saccharides and polyols) diet</a> can be a more effective and appropriate treatment than going gluten free. </p>
<h2>Awareness, diagnosis and management</h2>
<p>Inadequate and delayed diagnosis of coeliac disease remains a major problem in our community so improving awareness and testing is a major goal to reduce the burden of this disease. </p>
<p>Excitingly, there’s been significant progress in understanding the <a href="http://www.ncbi.nlm.nih.gov/pubmed/21219178">genetic and immunological basis</a> for why gluten is toxic in people with coeliac disease. Immune cells called T cells are the key mediators of damage in coeliac disease. These T cells are stimulated to cause damage by <a href="http://www.ncbi.nlm.nih.gov/pubmed/20650871">specific gluten fragments</a>, which have now been identified. </p>
<p>Such insights are allowing a variety of <a href="http://www.ncbi.nlm.nih.gov/pubmed/21401739">potential treatments</a> for coeliac disease to be explored, some of which will supplement and some of which could one day replace the gluten-free diet altogether.</p><img src="https://counter.theconversation.com/content/4928/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jason Tye-Din is affiliated with The Walter and Eliza Hall Institute and The Royal Melbourne Hospital. He receives funding from the NHMRC. He consults for ImmusanT Inc. and is co-inventor of patents related to the use of gluten peptides in diagnostics and therapies for coeliac disease.</span></em></p>The Neolithic Revolution introduced a whole range of new foods and proteins into the human digestive tract. But this phenomenal change created the perfect conditions for the rise of coeliac disease. While…Jason Tye-Din, Postdoctoral Scientist, Walter and Eliza Hall InstituteLicensed as Creative Commons – attribution, no derivatives.