tag:theconversation.com,2011:/global/topics/hunter-gatherer-10591/articlesHunter gatherer – The Conversation2023-05-30T12:24:25Ztag:theconversation.com,2011:article/2047722023-05-30T12:24:25Z2023-05-30T12:24:25Z‘Man, the hunter’? Archaeologists’ assumptions about gender roles in past humans ignore an icky but potentially crucial part of original ‘paleo diet’<figure><img src="https://images.theconversation.com/files/528374/original/file-20230525-25-e5g7ll.jpg?ixlib=rb-1.1.0&rect=743%2C0%2C4100%2C2866&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">What if prehistoric men and women joined forces in hunting parties?</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/tribe-of-hunter-gatherers-wearing-animal-skin-royalty-free-image/1194512906">gorodenkoff/iStock via Getty Images Plus</a></span></figcaption></figure><p>One of the most common stereotypes about the human past is that <a href="https://doi.org/10.1093/oxfordhb/9780199551224.013.032">men did the hunting while women did the gathering</a>. That gendered division of labor, the story goes, would have provided the meat and plant foods people needed to survive.</p>
<p>That characterization of our time as a species exclusively reliant on wild foods – before people <a href="https://doi.org/10.1073/pnas.1501711112">started domesticating plants and animals</a> more than 10,000 years ago – matches the pattern anthropologists observed among hunter-gatherers during the 19th and early 20th centuries. Virtually all of the large-game hunting they documented was performed by men.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/528430/original/file-20230525-27-1kn0er.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="stone points with centimeter ruler" src="https://images.theconversation.com/files/528430/original/file-20230525-27-1kn0er.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/528430/original/file-20230525-27-1kn0er.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/528430/original/file-20230525-27-1kn0er.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/528430/original/file-20230525-27-1kn0er.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/528430/original/file-20230525-27-1kn0er.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/528430/original/file-20230525-27-1kn0er.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/528430/original/file-20230525-27-1kn0er.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">Stone Folsom points, which date to between 11,000 and 10,000 years ago, are associated with the prehistoric hunting of bison.</span>
<span class="attribution"><span class="source">UMMAA 27673, 39802, 30442 and 37737, Courtesy of the University of Michigan Museum of Anthropological Archaeology</span></span>
</figcaption>
</figure>
<p>It’s an open question whether these ethnographic accounts of labor are truly representative of recent hunter-gatherers’ subsistence behaviors. Regardless, they definitely fueled assumptions that a gendered division of labor arose early in our species’ evolution. Current employment statistics do little to <a href="https://doi.org/10.1002/9781118900772.etrds0300">disrupt that thinking</a>; in a recent analysis, <a href="https://data.bls.gov">just 13% of hunters, fishers and trappers</a> in the U.S. were women.</p>
<p>Still, <a href="https://scholar.google.com/citations?hl=en&user=ph0ZKGEAAAAJ">as an archaeologist</a>, I’ve spent much of my career studying how people of the past got their food. <a href="https://doi.org/10.1002/evan.21979">I can’t always square my observations</a> with the “man the hunter” stereotype.</p>
<h2>A long-standing anthropological assumption</h2>
<p>First, I want to note that this article uses “women” to describe people biologically equipped to experience pregnancy, while recognizing that not all people who identify as women are so equipped, and not all people so equipped identify as women.</p>
<p>I am using this definition here because reproduction is at the heart of many hypotheses about when and why subsistence labor became a gendered activity. As the thinking goes, women gathered because it was a low-risk way to provide dependent children with a reliable stream of nutrients. Men hunted either to <a href="https://doi.org/10.1007/s12110-013-9173-0">round out the household diet</a> or to use difficult-to-acquire meat as a <a href="https://doi.org/10.1002/evan.20005">way to attract potential mates</a>.</p>
<p>One of the things that has come to trouble me about attempts to test related hypotheses using archaeological data – some of my own attempts included – is that they assume plants and animals are mutually exclusive food categories. Everything rests on the idea that plants and animals differ completely in how risky they are to obtain, their nutrient profiles and their abundance on a landscape.</p>
<p>It is true that highly mobile large-game species such as bison, caribou and guanaco (a deer-sized South American herbivore) were sometimes concentrated in places or seasons where plants edible to humans were scarce. But what if people could get the plant portion of their diets from the animals themselves? </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/528375/original/file-20230525-25-zpqjbl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="caribou grazing among lichen" src="https://images.theconversation.com/files/528375/original/file-20230525-25-zpqjbl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/528375/original/file-20230525-25-zpqjbl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=480&fit=crop&dpr=1 600w, https://images.theconversation.com/files/528375/original/file-20230525-25-zpqjbl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=480&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/528375/original/file-20230525-25-zpqjbl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=480&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/528375/original/file-20230525-25-zpqjbl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=603&fit=crop&dpr=1 754w, https://images.theconversation.com/files/528375/original/file-20230525-25-zpqjbl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=603&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/528375/original/file-20230525-25-zpqjbl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=603&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Herbivores can consume and digest some plant material that humans usually can’t.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/reindeer-caribou-close-up-of-a-male-animal-royalty-free-image/1352155127">pchoui/iStock via Getty Images Plus</a></span>
</figcaption>
</figure>
<h2>Animal prey as a source of plant-based food</h2>
<p>The plant material undergoing digestion in the stomachs and intestines of large ruminant herbivores is a not-so-appetizing substance called digesta. This <a href="http://www.twincitiesnaturalist.com/2009/10/secret-insides-of-deer-stomach.html">partially digested matter</a> is edible to humans and rich in carbohydrates, which are pretty much absent from animal tissues.</p>
<p>Conversely, animal tissues are rich in protein and, in some seasons, fats – nutrients unavailable in many plants or that occur in such small amounts that a person would need to eat impractically large quantities to meet daily nutritional requirements from plants alone.</p>
<p>If past peoples ate digesta, a big herbivore with a full belly would, in essence, be one-stop shopping for total nutrition.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/528432/original/file-20230525-23265-otdlhz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="two bison skulls facing camera" src="https://images.theconversation.com/files/528432/original/file-20230525-23265-otdlhz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/528432/original/file-20230525-23265-otdlhz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=246&fit=crop&dpr=1 600w, https://images.theconversation.com/files/528432/original/file-20230525-23265-otdlhz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=246&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/528432/original/file-20230525-23265-otdlhz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=246&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/528432/original/file-20230525-23265-otdlhz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=309&fit=crop&dpr=1 754w, https://images.theconversation.com/files/528432/original/file-20230525-23265-otdlhz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=309&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/528432/original/file-20230525-23265-otdlhz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=309&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Killing a bison could provide a source of both protein and carbs, if you consider the digesta.</span>
<span class="attribution"><span class="source">UMMAA 83209 a and b, Courtesy of the University of Michigan Museum of Anthropological Archaeology</span></span>
</figcaption>
</figure>
<p>To explore the <a href="https://doi.org/10.1002/evan.21979">potential and implications of digesta</a> as a source of carbohydrates, I recently compared institutional dietary guidelines to person-days of nutrition per animal using a 1,000-pound (450-kilogram) bison as a model. First I compiled available estimates for protein in a bison’s own tissues and for carbohydrates in digesta. <a href="https://doi.org/10.1002/evan.21979">Using that data, I found</a> that a group of 25 adults could meet the U.S. Department of Agriculture’s recommended daily averages for protein and carbohydrates for three full days eating only bison meat and digesta from one animal.</p>
<p>Among past peoples, consuming digesta would have relaxed the demand for fresh plant foods, perhaps changing the dynamics of subsistence labor. </p>
<h2>Recalibrating the risk if everyone hunts</h2>
<p>One of the risks typically associated with large-game hunting is that of failure. According to the evolutionary hypotheses around <a href="https://doi.org/10.1002/9781118900772.etrds0300">gendered division of labor</a>, when risk of hunting failure is high – that is, the likelihood of bagging an animal on any given hunting trip is low – women should choose more reliable resources to provision children, even if it means <a href="https://www.taylorfrancis.com/chapters/oa-edit/10.4324/9780203974131-26/foraging-differences-men-women">long hours of gathering</a>. The cost of failure is simply too high to do otherwise.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/528376/original/file-20230525-27-h86n7i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Circa 1850 artist's rendition of hunters under wolfskins approaching buffalo" src="https://images.theconversation.com/files/528376/original/file-20230525-27-h86n7i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/528376/original/file-20230525-27-h86n7i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=412&fit=crop&dpr=1 600w, https://images.theconversation.com/files/528376/original/file-20230525-27-h86n7i.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=412&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/528376/original/file-20230525-27-h86n7i.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=412&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/528376/original/file-20230525-27-h86n7i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=517&fit=crop&dpr=1 754w, https://images.theconversation.com/files/528376/original/file-20230525-27-h86n7i.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=517&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/528376/original/file-20230525-27-h86n7i.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=517&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">What 19th-century ethnographers recorded might not be a good representation of prehistoric conditions.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/hunters-hiding-under-white-wolf-skins-while-stalking-news-photo/3089698">MPI/Archive Photos via Getty Images</a></span>
</figcaption>
</figure>
<p>However, there is evidence to suggest that <a href="https://giscenter.isu.edu/Research/Projects/BisonPaper.pdf">large game was much more abundant</a> in North America, for example, before the 19th- and 20th-century ethnographers observed foraging behaviors. If high-yield resources like bison could have been acquired with low risk, and the animals’ digesta was also consumed, women may have been more likely to participate in hunting. Under those circumstances, hunting could have provided total nutrition, eliminating the need to obtain protein and carbohydrates from separate sources that might have been widely spread across a landscape.</p>
<p>And, statistically speaking, women’s participation in hunting would also have helped reduce the risk of failure. My models show that, if all 25 of the people in a hypothetical group participated in the hunt, rather than just the men, and all agreed to share when successful, each hunter would <a href="https://doi.org/10.1002/evan.21979">have had to be successful only about five times a year</a> for the group to subsist entirely on bison and digesta. Of course, real life is more complicated than the model suggests, but the exercise illustrates potential benefits of both digesta and female hunting.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/528377/original/file-20230525-27-dduale.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="black and white 1924 photo of two Inuit hunters with caribou carcass" src="https://images.theconversation.com/files/528377/original/file-20230525-27-dduale.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/528377/original/file-20230525-27-dduale.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=446&fit=crop&dpr=1 600w, https://images.theconversation.com/files/528377/original/file-20230525-27-dduale.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=446&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/528377/original/file-20230525-27-dduale.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=446&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/528377/original/file-20230525-27-dduale.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=560&fit=crop&dpr=1 754w, https://images.theconversation.com/files/528377/original/file-20230525-27-dduale.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=560&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/528377/original/file-20230525-27-dduale.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=560&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Winter in the Arctic offers Indigenous hunters more chances to kill herbivores than to find edible plants.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/two-inuit-hunters-in-canada-strip-the-meat-from-a-pair-of-news-photo/50851064">Topical Press Agency/Hulton Archive via Getty Images</a></span>
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<p>Ethnographically documented foragers did routinely eat digesta, especially where herbivores were plentiful but plants edible to humans were scarce, <a href="https://www2.dmu.dk/1_viden/2_publikationer/3_fagrapporter/rapporter/fr528.pdf">as in the Arctic</a>, where prey’s stomach contents was an important source of carbohydrates. </p>
<p>I believe eating digesta may have been a more common practice in the past, but direct evidence is frustratingly hard to come by. In at least one instance, plant species present in the mineralized plaque of a Neanderthal individual’s teeth <a href="https://doi.org/10.1016/j.quascirev.2013.09.003">point to digesta as a source of nutrients</a>. To systematically study past digesta consumption and its knock-on effects, <a href="https://doi.org/10.1086/507197">including female hunting</a>, researchers will need to draw on <a href="https://doi.org/10.1126/sciadv.abd0310">multiple lines of archaeological evidence</a> and insights gained from models like the ones I developed.</p><img src="https://counter.theconversation.com/content/204772/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Raven Garvey does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>If hunter-gatherers went beyond nose-to-tail eating to include the undigested plant matter in a prey animal’s stomach, assumptions about gendered division of labor start to fall apart.Raven Garvey, Associate Professor of Anthropology; Curator of High Latitude and Western North American Archaeology, Museum of Anthropological Archaeology; Faculty Affiliate, Research Center for Group Dynamics, University of MichiganLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1586022021-05-19T20:15:21Z2021-05-19T20:15:21ZEvolutionary medicine looks to our early human ancestors for insight into conditions like diabetes<figure><img src="https://images.theconversation.com/files/401702/original/file-20210519-23-iftf0.jpg?ixlib=rb-1.1.0&rect=1477%2C0%2C3514%2C1970&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Our ancestors' environment and diets, and the limits of our biology, have led to adaptations that have improved human survival through natural selection. But we remain prone to illness and disease anyway.</span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><p>Like all living things, humans are the product of a complex evolutionary history. Our ancestors’ environment and diets, and the limits of human biology, have led to adaptations that have improved our survival through natural selection. Despite these adaptations, our bodies remain prone to illness and disease. If we have evolved and adapted to our environment, why do we still get sick? </p>
<p>While remarkable at understanding the mechanisms of illness and disease, modern medicine can often overlook the underlying reasons for their emergence. <a href="https://evmed.asu.edu/blog/evolutionary-medicine-top-ten-questions">Evolutionary medicine</a> argues that understanding our ancestral history and the evolutionary reasons for illness can explain disease prevalence and provide insight for clinical care. </p>
<p>This evolutionary perspective counters the “bio-ethnocentrism” of modern medicine — the idea that what is “healthy” or “normal” is largely based on those of northern or western European descent. Our global population is incredibly diverse, so having one definition of “normal” just doesn’t make sense. </p>
<p>For example, the inability to digest lactose, resistance to malaria and the human affinity for high-fat and sugary foods are all products of evolution. Examining these conditions through an evolutionary lens can provide unique insight into how we understand disease, and how we can redefine “normal.” </p>
<h2>Lactose intolerance</h2>
<figure class="align-right ">
<img alt="Glass of milk" src="https://images.theconversation.com/files/401188/original/file-20210518-17-7a43j6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/401188/original/file-20210518-17-7a43j6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=896&fit=crop&dpr=1 600w, https://images.theconversation.com/files/401188/original/file-20210518-17-7a43j6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=896&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/401188/original/file-20210518-17-7a43j6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=896&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/401188/original/file-20210518-17-7a43j6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1126&fit=crop&dpr=1 754w, https://images.theconversation.com/files/401188/original/file-20210518-17-7a43j6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1126&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/401188/original/file-20210518-17-7a43j6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1126&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Adult lactose intolerance is a global norm, not an exception or an illness.</span>
<span class="attribution"><span class="source">(Piqsels)</span></span>
</figcaption>
</figure>
<p><a href="https://www.mayoclinic.org/diseases-conditions/lactose-intolerance/symptoms-causes/syc-20374232">Lactose intolerance</a> occurs when we can’t digest milk sugars (lactose) in adulthood. This can cause nausea, cramping, gas and diarrhea, and is considered a medical condition. </p>
<p>Lactose is broken down by the enzyme lactase. Adult production of lactase evolved in human populations that domesticated animals about 10,000 years ago. These populations were found in northern and central Europe, and in pastoral communities in Africa. Milk is a calorie- and nutrient-dense food, meaning that people who could digest lactose would be better nourished, giving them a better chance at survival and reproduction. </p>
<p>Mutations allowing for adult digestion of lactose gradually spread over generations within these populations. However, those with ancestors from populations that did not regularly herd and milk domesticated animals, such as Indigenous populations in North and South America and most Asian populations, do not possess this ability. In fact, roughly <a href="https://doi.org/10.1098/rstb.2010.0268">65 per cent of adults worldwide remain lactose intolerant</a>. </p>
<p>If 65 per cent of the global population cannot digest lactose, why is it treated as an illness? There is nothing “wrong” with someone who is lactose intolerant; no intervention is needed other than to avoid or limit dairy consumption. Evolution tells us that lactose intolerance is perfectly normal. We simply need to redefine illness. </p>
<h2>Sickle cell disease</h2>
<p>Humans share a <a href="https://www.nature.com/scitable/topicpage/natural-selection-uncovering-mechanisms-of-evolutionary-adaptation-34539/">long evolutionary history with the parasite that causes malaria</a> (Plasmodium). Malaria infects and kills millions of people each year. Over time, humans have evolved adaptations to counter the parasite. One of these adaptations is a mutation in the beta hemoglobin gene.</p>
<p>There are two versions of the beta haemoglobin gene. One is normal, while the other is a mutation that causes sickle-shaped red blood cells. Carrying a copy of the mutated gene confers resistance to malaria, but those carrying two copies of the mutated gene also suffer from <a href="https://www.cdc.gov/ncbddd/sicklecell/facts.html">sickle cell disease</a> (SCD). </p>
<p>SCD is a heritable condition that causes dominant crescent-shaped red blood cells that cannot transport oxygen effectively. People with SCD can experience anemia, acute pain, organ damage and other life-threatening symptoms. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/399111/original/file-20210506-15-i4j34a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Four round red blood cells and one sickle-shaped red blood cell" src="https://images.theconversation.com/files/399111/original/file-20210506-15-i4j34a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/399111/original/file-20210506-15-i4j34a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=678&fit=crop&dpr=1 600w, https://images.theconversation.com/files/399111/original/file-20210506-15-i4j34a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=678&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/399111/original/file-20210506-15-i4j34a.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=678&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/399111/original/file-20210506-15-i4j34a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=852&fit=crop&dpr=1 754w, https://images.theconversation.com/files/399111/original/file-20210506-15-i4j34a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=852&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/399111/original/file-20210506-15-i4j34a.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=852&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Microscopic image of several normal red blood cells and a sickle cell.</span>
<span class="attribution"><span class="source">(Janice Haney Carr/CDC/ Sickle Cell Foundation of Georgia)</span></span>
</figcaption>
</figure>
<p>If natural selection removes mutations that negatively affect reproduction and survival, then genes like the mutated beta hemoglobin should have disappeared or become exceedingly rare. Yet sickle cell disease is relatively common, especially among people who descended from some regions of Africa. </p>
<p>The advantage of being resistant to malaria comes at the cost of having high rates of SCD in the population. Selection for malaria resistance is so strong that several mutations causing SCD have occurred independently in different regions of Africa. </p>
<p>The prevalence of malaria in these regions means that sickle cell disease predominately strikes those with African ancestry. The <a href="http://doi.org/10.1056/NEJMp2022125">societal implications</a> of this evolutionary history are profound. Lack of awareness of racial differences in SCD combined with generalized symptoms mean that the disease is easily missed by Western practitioners. </p>
<p>Understanding the evolutionary origins of this condition should be used to both educate health-care practitioners and to dismantle the bio-ethnocentrism of medicine.</p>
<h2>Mismatch diseases</h2>
<p>One of the fundamental concepts of evolutionary medicine is the idea that our bodies are adapted for a pre-industrial lifestyle, resulting in a “mismatch” to our current environment. Diseases stemming from this are appropriately referred to as <a href="https://doi.org/10.1093/emph/eoy023">mismatch diseases</a>. </p>
<figure class="align-left ">
<img alt="Illustration of stone age hunters" src="https://images.theconversation.com/files/401187/original/file-20210518-15-3whnxy.jpg?ixlib=rb-1.1.0&rect=224%2C274%2C16416%2C12399&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/401187/original/file-20210518-15-3whnxy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/401187/original/file-20210518-15-3whnxy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/401187/original/file-20210518-15-3whnxy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/401187/original/file-20210518-15-3whnxy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/401187/original/file-20210518-15-3whnxy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/401187/original/file-20210518-15-3whnxy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Our hunter-gatherer ancestors adapted to crave energy-dense foods and conserve physical energy. However, these traits are no longer advantageous in a post-industrial world, and are linked with conditions such as obesity and Type 2 diabetes.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<p>Underlying many of these mismatch diseases is the energy imbalance that post-industrial life affords; eating too much and moving too little. Humans are adapted to avoid negative energy balance (burning more calories than we eat) because it reduces reproductive success and survival. </p>
<p>This requires a reduction in physical activity or an increase in the consumption of food. Because of this, <a href="https://news.harvard.edu/gazette/story/2021/01/daniel-lieberman-busts-exercising-myths/">humans have adapted to be fairly lazy</a>, and <a href="http://darwinian-medicine.com/the-reasons-you-crave-sugar-part-1/">crave energy-dense foods</a>.</p>
<p>These adaptations were not a problem when food was less abundant, and required significant effort to acquire. Fundamentally, obesity is the result of this positive energy imbalance. <a href="https://www.npr.org/transcripts/227777434">Type 2 diabetes is also the result of an energy imbalance</a>, often caused by chronic consumption of high-sugar and high-fat diets. </p>
<p>The <a href="https://dx.doi.org/10.1016%2Fj.psc.2011.08.005">difficulty associated with reducing diabetes and obesity</a> is the result of the modern environment. The most abundant foods are high in fat and sugars, and low in fibre. The wild meats and plant-based foods <a href="https://doi.org/10.1038/sj.ejcn.1601353">consumed by hunter-gatherer communities</a> have now been replaced by ultra-processed and refined foods. </p>
<p>On top of this, modern activity levels are relatively low. Elevators, escalators and cars have reduced the need to expend energy. And while activity levels are not as high as you might predict for hunter-gatherers, it’s more than today’s sedentary lifestyle.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/401704/original/file-20210519-19-1q0skki.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A reconstructed skull in the foreground and the head and shoulders of a skeleton in the background" src="https://images.theconversation.com/files/401704/original/file-20210519-19-1q0skki.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/401704/original/file-20210519-19-1q0skki.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=447&fit=crop&dpr=1 600w, https://images.theconversation.com/files/401704/original/file-20210519-19-1q0skki.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=447&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/401704/original/file-20210519-19-1q0skki.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=447&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/401704/original/file-20210519-19-1q0skki.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=562&fit=crop&dpr=1 754w, https://images.theconversation.com/files/401704/original/file-20210519-19-1q0skki.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=562&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/401704/original/file-20210519-19-1q0skki.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=562&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A reconstructed Neanderthal skeleton, right, and a model of a modern human skeleton, left, on display at the Museum of Natural History in New York.</span>
<span class="attribution"><span class="source">(AP Photo/Frank Franklin II)</span></span>
</figcaption>
</figure>
<p>Our preferences for high-fat, high-sugar and salty foods are a consequence of adaptations for avoiding a negative energy balance. It’s important to imagine that in a landscape where food was scarce, those who carried a genetically determined preference for energy-rich foods would have had an evolutionary advantage. </p>
<p>These mismatch diseases emphasize how quickly human cultural development has outpaced human evolution, and the negative consequences of easy living.</p>
<h2>Why does it matter?</h2>
<p>Understanding the evolution of humans and disease lays the foundation for developing treatments that address the underlying basis for illness and assesses differences in disease vulnerability stemming from ancestral diversity. </p>
<p>A more profound understanding of our evolution is necessary to offer better health care to our entire community. Before medicine can move forward, we must understand where we came from.</p><img src="https://counter.theconversation.com/content/158602/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Albrecht Schulte-Hostedde receives funding from the Natural Sciences and Engineering Research Council and the Ontario Ministry of Natural Resources and Forestry. </span></em></p><p class="fine-print"><em><span>Eric Boivin and Meghan McCue do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Evolutionary medicine uses our ancestral history to explain disease prevalence and inform care for conditions like Type 2 diabetes. It also challenges the bio-ethnocentrism of western medicine.Albrecht Schulte-Hostedde, Professor - Applied Evolutionary Ecology, Laurentian UniversityEric Boivin, Graduate Student - Department of Psychology, Laurentian UniversityMeghan McCue, PhD Candidate, Biomolecular Sciences, Laurentian UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1494772020-11-04T21:08:19Z2020-11-04T21:08:19ZDid prehistoric women hunt? New research suggests so<figure><img src="https://images.theconversation.com/files/367451/original/file-20201104-13-zrxzcx.jpg?ixlib=rb-1.1.0&rect=0%2C38%2C1024%2C882&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Artist impression of a prehistoric woman hunting.</span> <span class="attribution"><span class="source">Matthew Verdolivo (UC Davis IET Academic Technology Services)</span></span></figcaption></figure><p>For a long time, it was assumed that hunting in prehistoric societies was primarily <a href="https://www.jstor.org/stable/10.1086/595620?seq=1">carried out by men</a>. Now <a href="https://advances.sciencemag.org/lookup/doi/10.1126/sciadv.abd0310">a new study</a> adds to a body of evidence challenging this idea. The research reports the discovery of a female body, buried alongside hunting tools, in the Americas some 9,000 years ago.</p>
<p>The woman, discovered in the Andean highlands, was dubbed Wilamaya Patjxa individual 6, or “WPI6”. She was found with her legs in a semi-flexed position, with the collection of stone tools placed carefully next to them. These included projectile points – tools that were likely used to tip lightweight spears thrown with an <a href="https://www.britishmuseum.org/collection/object/E_Am1954-05-2657">atlatl</a>(also called a spear thrower). The authors argue that such projectile points were used for hunting large animals.</p>
<p>WPI6 was between 17 and 19 years old at time of death. It was an analysis of substances known as “peptides” in her teeth – which are <a href="https://www.pnas.org/content/114/52/13649">markers for biological sex</a> - that showed that she was female. There were also large mammal bones in the burial fill, demonstrating the significance of hunting in her society. </p>
<figure class="align-center ">
<img alt="Picture of the excavations at Wilamaya Patjxa." src="https://images.theconversation.com/files/367453/original/file-20201104-17-1ge9wd4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/367453/original/file-20201104-17-1ge9wd4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/367453/original/file-20201104-17-1ge9wd4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/367453/original/file-20201104-17-1ge9wd4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/367453/original/file-20201104-17-1ge9wd4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/367453/original/file-20201104-17-1ge9wd4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/367453/original/file-20201104-17-1ge9wd4.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">Excavations at Wilamaya Patjxa.</span>
<span class="attribution"><span class="source">Randall Haas</span></span>
</figcaption>
</figure>
<p>The authors of the study, published in Science Advances, also reviewed evidence of other skeletons buried around the same period in the Americas, looking specifically at graves containing similar tools associated with big-game hunting. They found that of the 27 skeletons for which sex could be determined, 41% were likely female. </p>
<p>The authors propose that this may mean that big-game hunting was indeed carried out by both men and women in hunter-gatherer groups at that time in the Americas. </p>
<h2>Competing hypotheses</h2>
<p>This idea goes against a hypothesis, dating back to the 1960s, known as the “<a href="https://www.oxfordhandbooks.com/view/10.1093/oxfordhb/9780199551224.001.0001/oxfordhb-9780199551224-e-032?rskey=PyMNIZ&result=1">Man-The-Hunter model</a>”, which is increasingly being debunked. It suggests that hunting, and especially big game hunting, was primarily, if not exclusively, undertaken by male members of past hunter-gatherer societies. </p>
<p>The hypothesis is based on a few different lines of evidence. Probably most significantly, it considers recent and present-day hunter-gatherer societies to try to understand how those in the deeper past may have been organised. </p>
<p>The stereotypical view of hunter-gatherer groups is that they involve a gendered division of labour, with men hunting and women being more likely to stay nearer home with young children, or fish and forage, though even then <a href="https://srcd.onlinelibrary.wiley.com/doi/abs/10.1111/cdev.13306">there is some variation</a>. For example, among <a href="https://www.culturalsurvival.org/publications/cultural-survival-quarterly/agta-forager-women-philippines">Agta foragers in the Philippines</a> women are primary hunters rather than assistants.</p>
<p>Some present day hunter-gatherers still use atlatls today, and some people also <a href="https://worldatlatl.org/">enjoy using atlatls</a> in competitive throwing events, with women and children regularly taking part. Archaeologists studying <a href="https://www.tandfonline.com/doi/abs/10.1179/pan.2006.016">data from these events</a> suggest that atlatls may well have been equalisers – facilitating hunting by both women and men, possibly because they reduce the importance of body size and strength.</p>
<p>The new study further debunks the hypothesis, adding to a few previous archaeological findings. For example, at the 34,000-year-old site of Sunghir in Russia, archaeologists <a href="https://www.sapiens.org/archaeology/paleolithic-burial-sunghir/">discovered the burial of two youngsters</a> – one of whom was likely a girl of around nine to 11 years old. Both individuals had physical abnormalities, and were buried with 16 mammoth ivory spears – an incredible offering of what were probably valuable hunting tools.</p>
<figure class="align-center ">
<img alt="Randall Haas" src="https://images.theconversation.com/files/367458/original/file-20201104-19-lph8du.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/367458/original/file-20201104-19-lph8du.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/367458/original/file-20201104-19-lph8du.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/367458/original/file-20201104-19-lph8du.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/367458/original/file-20201104-19-lph8du.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/367458/original/file-20201104-19-lph8du.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/367458/original/file-20201104-19-lph8du.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">
<figcaption>
<span class="caption">The Andes Mountains.</span>
<span class="attribution"><span class="source">Picture of the Andes Mountains.</span></span>
</figcaption>
</figure>
<p>In 2017, a famous burial of a Viking warrior from Sweden, discovered early in the 20th century and long assumed to be male, <a href="https://onlinelibrary.wiley.com/doi/full/10.1002/ajpa.23308">was discovered to be biologically female</a>. This finding caused a significant and somewhat surprising amount of debate, and points to how our own modern ideas of gender roles can affect interpretations of more recent history too. </p>
<p>It has been argued that distinguishing between “boys jobs and girls jobs”, as one former British prime minister <a href="https://www.independent.co.uk/news/uk/politics/theresa-may-philip-may-husband-boy-jobs-girls-one-show-take-bins-out-bbc-prime-minister-marriage-a7727481.html">put it</a>, could have evolutionary advantages. For example, it can allow pregnant and lactating mothers to stay near to a home base, keeping themselves and youngsters protected from harm. But we are increasingly learning that this model is far too simplistic. </p>
<p>With hunting being a keystone to survival for many highly mobile hunter-gatherer groups, community-wide participation also makes good evolutionary sense. The past, as some say, is a foreign country, and the more evidence we have, the more variable human behaviour looks to have been.</p><img src="https://counter.theconversation.com/content/149477/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Annemieke Milks has previously received research funding from the Arts and Humanities Research Council, The Leakey Foundation, and The Wenner-Gren Foundation. </span></em></p>New research is challenging the hypothesis that men did the hunting in prehistoric societies.Annemieke Milks, Honorary Research Fellow, UCLLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/919342018-02-16T10:57:29Z2018-02-16T10:57:29ZFive surprising things DNA has revealed about our ancestors<figure><img src="https://images.theconversation.com/files/206616/original/file-20180215-131010-86ag3v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Cheddar man.</span> <span class="attribution"><span class="source">Channel 4</span></span></figcaption></figure><p>Researchers recently used DNA from the 10,000-year-old “Cheddar Man”, one of Britain’s oldest skeletons, to unveil what the first inhabitants of what now is Britain actually looked like. But this isn’t the first time DNA from old skeletons has provided intriguing findings about our ancestors. Rapid advances in genetic sequencing over the past few decades have opened up a whole new window into the past.</p>
<h2>1. Our ancestors had sex with Neanderthals</h2>
<p>Archaeologists have known for some time that modern humans and Neanderthals lived together in Europe and Asia, but until recently the nature of their cohabitation was unknown.</p>
<p>In fact, after the first <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2602844/">full Neanderthal mitochondrial genome</a> (DNA located in the cell’s mitochondria) was sequenced in 2008, there was still uncertainty among both archaeologists and <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2374707/">geneticists</a> as to whether humans interbred with our closest relative.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/206618/original/file-20180215-131013-1imhpbp.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/206618/original/file-20180215-131013-1imhpbp.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=312&fit=crop&dpr=1 600w, https://images.theconversation.com/files/206618/original/file-20180215-131013-1imhpbp.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=312&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/206618/original/file-20180215-131013-1imhpbp.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=312&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/206618/original/file-20180215-131013-1imhpbp.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=392&fit=crop&dpr=1 754w, https://images.theconversation.com/files/206618/original/file-20180215-131013-1imhpbp.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=392&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/206618/original/file-20180215-131013-1imhpbp.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=392&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The look of love. Human and Neanderthal skulls.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Sapiens_neanderthal_comparison_en_blackbackground.png">DrMikeBaxter/wikimedia</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>When the <a href="http://science.sciencemag.org/content/328/5979/710.full">full genome of a Neanderthal</a> was sequenced in 2010, comparisons with modern human DNA showed that all non-African people have pieces of Neanderthal DNA in their genomes. This could have occurred if humans and Neanderthal had interbred around just 50,000 years ago, <a href="https://www.nature.com/articles/nature14558">a result that was confirmed</a> a few years later.</p>
<h2>2. Interbreeding enabled Tibetans to live in mountains</h2>
<p>Amazingly, it wasn’t just trysts with Neanderthals that kept our ancestors busy. When DNA was sequenced from a fossilised finger from a cave in the Altai mountains of Siberia, which was thought to be Neanderthal, genetic analysis showed that it was actually a <a href="https://www.nature.com/articles/nature08976">new species of human</a>, distinct from but closely related to Neanderthals. Analysis of <a href="http://science.sciencemag.org/content/338/6104/222">its full genome </a> showed that these “<a href="http://discovermagazine.com/2016/dec/meet-the-denisovans">Denisovans</a>” also had sex with our ancestors.</p>
<p>Tibetans, who live among some of the highest mountains in the world, are able to survive at altitudes where most people are encumbered by the lack of oxygen. Genetic analysis has shown that Tibetans, along with Ethiopian and Andean mountain dwellers, have special genetic adaptations that allow them to process oxygen in this rarefied mountain air.</p>
<p>We now know that these genetic adaptations to altitude in Tibetans – they have a specific variant of a gene called EPAS1 - were in fact <a href="https://www.nature.com/articles/nature13408">inherited through ancestral mating with Denisovans</a>. </p>
<p>It turns out that improvements in <a href="https://www.nature.com/articles/nrg3936">immunity, metabolism and diet</a> among modern humans are also due to beneficial genetic variants inherited through this interbreeding with both Neanderthals and Denisovans.</p>
<h2>3. Our ancestors evolved surprisingly quickly</h2>
<p>Interbreeding accounts only for a tiny amount of human adaptation around the world. Analyses of DNA are showing us that, as our ancestors moved around the world, they evolved to different environments and diets far more quickly than was originally thought.</p>
<p>For example, the textbook example of a human adaptation is the evolution of lactose tolerance. The ability to digest milk past the age of three is not universal – and was previously assumed to have spread into Europe with agriculture from the Middle East starting some 10,000 years ago.</p>
<p>But when we look at the DNA of people over the past 10,000 years, this adaptation – which is now commonplace in northern Europe – was not present until around <a href="https://www.nature.com/articles/nature16152">around 4,000 years ago</a>, and even then <a href="http://www.annualreviews.org/doi/full/10.1146/annurev-genom-091416-035340">it was still quite rare</a>. This means that the spread of lactose tolerance across Europe must have occurred incredibly quickly.</p>
<h2>4. The first British people were black</h2>
<p>DNA from one of Britain’s fist people, Cheddar Man, shows that he was very likely to have dark brown skin and blue eyes. And, despite his eponym, we also know from his DNA that he couldn’t digest milk.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/206619/original/file-20180215-131016-hqie7g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/206619/original/file-20180215-131016-hqie7g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=391&fit=crop&dpr=1 600w, https://images.theconversation.com/files/206619/original/file-20180215-131016-hqie7g.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=391&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/206619/original/file-20180215-131016-hqie7g.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=391&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/206619/original/file-20180215-131016-hqie7g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=491&fit=crop&dpr=1 754w, https://images.theconversation.com/files/206619/original/file-20180215-131016-hqie7g.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=491&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/206619/original/file-20180215-131016-hqie7g.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=491&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Cheddar man skeleton.</span>
<span class="attribution"><span class="source">Channel 4</span></span>
</figcaption>
</figure>
<p>While it’s fascinating, and perhaps surprising, to learn that some of the first people to inhabit the island that is now known as Britain had dark skin and blue eyes, this striking combination is not altogether unpredictable given what we’ve learnt about Paleolithic Europe from ancient DNA. <a href="https://www.nature.com/articles/nature12960">Dark skin</a> was actually <a href="https://www.nature.com/articles/nature14507">quite common</a> in hunter gatherers such as Cheddar Man who were living in Europe in the millenia after he was alive – and blue eyes have been around <a href="https://www.nature.com/articles/nature17993">since the Ice Age</a>.</p>
<h2>5. Immigrants from the East brought white skin to Europe</h2>
<p>So, if dark skin was common in Europe 10,000 years ago, how did Europeans get their white skin? There are no hunter gatherers left in Europe, and very few remaining around the world. Agriculture has replaced hunting as a way of life, and in Europe we know that farming <a href="https://theconversation.com/neolithic-bling-provides-clues-to-spread-of-farming-in-europe-39848">spread from the Middle East</a>. Genetics has taught us that this change also involved significant <a href="https://www.nature.com/articles/nature13673">movement of people</a>.</p>
<p>We also now know that there was also a large influx of people from the Russian and Ukrainian Steppe around <a href="https://www.nature.com/articles/nature14317">5,000 years ago</a>. As well as DNA, the <a href="https://theconversation.com/ancient-dna-reveals-how-europeans-developed-light-skin-and-lactose-tolerance-43078">Yamnaya</a> people brought domesticated horses and the wheel into Europe – and maybe even proto-Indo-European, the language from which almost all modern European languages originate. </p>
<p>A good bet for where white skin came from is that is was introduced by either the Yamnaya or Middle Eastern immigrant groups. It will have then become ubiquitous as a result of its benefit as an adaptation to low levels of sunlight – light skin pigmentation is thought to help people better absorb sunlight and synthesise vitamin D from it.</p><img src="https://counter.theconversation.com/content/91934/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>George Busby receives funding from the Wellcome Trust and the Medical Research Council. </span></em></p>The first British people were black – and other interesting findings made possible by genomic sequencing.George Busby, Scientific Product Manager, University of OxfordLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/897032018-01-10T10:19:00Z2018-01-10T10:19:00ZAncient DNA sheds light on the mysterious origins of the first Scandinavians<figure><img src="https://images.theconversation.com/files/200941/original/file-20180105-26157-1rs4xib.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption"> Skeletal fragments from Hummervikholmen, one of sites featured in this study.
</span> <span class="attribution"><span class="source">Beate Kjørslevik</span></span></figcaption></figure><p>Tracking the migration of humans <a href="https://theconversation.com/heres-how-genetics-helped-crack-the-history-of-human-migration-52918">isn’t easy</a>, but genetics is helping us uncover new information at breathtaking speed. We know that our species originated in Africa and likely reached Europe from the southeast no later than 42,000 years ago. During the last ice age some 33,000-20,000 years ago, when a permanent ice sheet covered northern and parts of central Europe, modern humans in southwest Europe were isolated from groups further to the east. </p>
<p>When the ice sheet retreated, some of these hunter gatherers eventually colonised Scandinavia from the south about 11,700 years ago, making it one of the last areas of Europe to be inhabited. But exactly who these individuals were and how they got there has remained a puzzle for researchers. Now we have sequenced the genomes of seven hunter gatherers, dated to be 9,500-6,000 years old, to find out.</p>
<p>One of the reasons the origins of the first Scandinavians is so enigmatic is a major shift in stone tool technology that appeared soon after they got there. This new technology seemed to have had an origin in eastern Europe and <a href="http://dx.doi.org/10.1016/j.quaint.2014.02.023">it has been an open question</a> how it reached Scandinavia.</p>
<h2>Early migration</h2>
<p>Our interdisciplinary research team combined genetic and archaeological data with reconstructions of the ice sheets to investigate the earliest people of the Scandinavian peninsula. We extracted DNA for sequencing from bones and teeth of the seven individuals from the Norwegian Atlantic coast and the Baltic islands of Gotland and Stora Karlsö. </p>
<p>We then compared the genomic data with the genetic variation of contemporary hunter gatherers from other parts of Europe. To our surprise, hunter gatherers from the Norwegian Atlantic coast were genetically more similar to contemporaneous populations from east of the Baltic Sea, while hunter gatherers from what is Sweden today were genetically more similar to those from central and western Europe. One could say that – in Scandinavia at that time – the geographic west was the genetic east and vice versa. </p>
<p>This contradiction between genetics and geography can only be explained by two main migrations into Scandinavia. It would have started with an initial pulse from the south – modern day Denmark and Germany – that took place just after 11,700 years ago. Then there would have been an additional migration from the northeast, following the Atlantic coast in northern Finland and Norway becoming free of ice.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/201036/original/file-20180106-26151-14ho100.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/201036/original/file-20180106-26151-14ho100.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/201036/original/file-20180106-26151-14ho100.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/201036/original/file-20180106-26151-14ho100.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/201036/original/file-20180106-26151-14ho100.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/201036/original/file-20180106-26151-14ho100.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/201036/original/file-20180106-26151-14ho100.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Artist’s impression of the last ice age.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Last_glacial_period#/media/File:IceAgeEarth.jpg">wikipedia</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>These results, <a href="http://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2003703">published in the PLOS Biology</a>, agree with archaeological observations that the earliest occurrences of the new stone tool technology in Scandinavia were recorded in Finland, northwest Russia and Norway – dating to about 10,300 years ago. This kind of technology only appeared in southern Sweden and Denmark later on.</p>
<h2>Blue eyes, blonde hair</h2>
<p>Knowing the genomes of these hunter gatherer groups also allowed us to look deeper into the population dynamics in stone age Scandinavia. One consequence of the two groups mixing was a surprisingly large number of genetic variants in Scandinavian hunter gatherers. These groups were genetically more diverse than the groups that lived in central, western and southern Europe at the same time. That is in stark contrast to the pattern we see today where more genetic variation is found in southern Europe and less in the north.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/201325/original/file-20180109-36016-1igvk0b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/201325/original/file-20180109-36016-1igvk0b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=456&fit=crop&dpr=1 600w, https://images.theconversation.com/files/201325/original/file-20180109-36016-1igvk0b.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=456&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/201325/original/file-20180109-36016-1igvk0b.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=456&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/201325/original/file-20180109-36016-1igvk0b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=573&fit=crop&dpr=1 754w, https://images.theconversation.com/files/201325/original/file-20180109-36016-1igvk0b.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=573&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/201325/original/file-20180109-36016-1igvk0b.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=573&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Axe, fish hook and other stone tools from the earliest Scandinavians, found in a cave on Gotland.</span>
<span class="attribution"><span class="source">Jan Apel</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The two groups that came to Scandinavia were originally genetically quite different, and displayed distinct physical appearances. The people from the south had blue eyes and relatively dark skin. The people from the northeast, on the other hand, had a variation of eye colours and pale skin.</p>
<p>Originally, humans are a species from warmer climates closer to the equator and we mainly cope with challenging environments with specific behaviour and technology. This includes making fires, clothes and specialised hunting equipment. However, in the long term there is also potential for adaptation through genetic changes. </p>
<p>For example, we found that genetic variants associated with light skin and eye pigmentation were carried, on average, in greater frequency among Scandinavian hunter gatherers than their ancestors from other parts of Europe. Scientists believe that light skin pigmentation <a href="https://www.livescience.com/7863-people-white.html">helps people better absorb sunlight</a> and synthesise vitamin D from it. </p>
<p>That suggests that local adaptation to the high-latitude climate associated with low levels of sunlight and low temperatures took place in Scandinavia after these groups arrived. In fact, this is in agreement with the worldwide pattern of pigmentation <a href="https://www.ncbi.nlm.nih.gov/books/NBK210015/">decreasing with distance to the equator</a>.</p>
<p>Modern people of northern Europe trace relatively little genetic ancestry back to the early Scandinavians studied by us. That’s because several later migrations have changed the Scandinavian gene pool over time. We know that migrations during the later stone age, the bronze age and historical times have brought new genetic material as well as novel technologies, cultures and languages. </p>
<p>The picture is similarly complex in other parts of the world. Hopefully it won’t be long before genetics helps us work out the detailed picture of exactly how humans have spread across the world since we first emerged.</p><img src="https://counter.theconversation.com/content/89703/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jan Apel receives funding from Swedish Research Council, Berit Wallenberg Foundation and Palmska fonden</span></em></p>Scandinavia was populated by two main migrations, making its first inhabitants more genetically diverse and adapted to harsh climates than those in the rest of Europe.Jan Apel, Senior Lecturer of Archaeology, Lund UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/793032017-06-19T20:12:28Z2017-06-19T20:12:28ZAfrican court’s landmark ruling gives hope to rural people across the continent<figure><img src="https://images.theconversation.com/files/173791/original/file-20170614-27725-knesjx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Ogiek leaders wait to hear the African Court's ruling</span> <span class="attribution"><span class="source">Daniel Kobei</span></span></figcaption></figure><p>The still new <a href="http://en.african-court.org/">African Court on Human and Peoples’ Rights</a> has issued a landmark judgement for marginalised communities across Africa. It <a href="http://en.african-court.org/images/Cases/Judgment/Application%20006-2012%20-%20African%20Commission%20on%20Human%20and%20Peoples%E2%80%99%20Rights%20v.%20the%20Republic%20of%20Kenya..pdf">ruled</a> that the Kenyan government violated the rights of the Mau Ogiek people by evicting them from their ancestral land in the <a href="http://www.awf.org/landscape/mau-forest-complex">Mau Forest complex</a>.</p>
<p>Before taking their case to the African court, the Mau Ogiek had waged a long battle in a national court against routine evictions which the government has justified <a href="http://www.ogiek.org/">on the grounds</a> of concerns about the environment. </p>
<p>The court for human and people’s rights rejected these claims. It concluded that eviction from their ancestral forest territories violated the <a href="http://www.achpr.org/instruments/achpr/">African Charter on Human and Peoples’ Rights</a>, the founding continental law to which all members of the African Union are party. </p>
<p>The court was <a href="http://en.african-court.org/">established</a> by African states in 2006 to ensure the protection of human and peoples’ rights in Africa. It has so far finalised 32 cases. Its work compliments that of the <a href="http://www.achpr.org/">African Commission on Human and Peoples Rights</a> – which acted on behalf of the Ogiek. The Ogiek case is the <a href="http://minorityrights.org/2017/05/26/huge-victory-kenyas-ogiek-african-court-sets-major-precedent-indigenous-peoples-land-rights/">first time</a> the court has ruled on an indigenous peoples’ rights case or in a case with mass human rights violations indicated.</p>
<p>This is why the decision <a href="https://www.amnesty.org/en/latest/news/2017/05/kenya-ruling-in-ogiek-case-gives-hope-to-indigenous-peoples-everywhere/">matters</a> a great deal. Not only for Africans who define themselves as indigenous people but for all rural dwellers who own land on the basis of <a href="https://books.google.co.ke/books?id=k6nfDQAAQBAJ&pg=PA475&lpg=PA475&dq=Liz+alden+wily+in+graziadei+and+smith+eds+comparative+property+law&source=bl&ots=XtJ_lJnjkV&sig=RBAK7gjF2h9WprGVuWIeG6Tq0LM&hl=en&sa=X&redir_esc=y#v=onepage&q=Liz%20alden%20wily%20in%20graziadei%20and%20smith%20eds%20comparative%20property%20law&f=false">customary law</a>. Their numbers are expected to rise to <a href="https://esa.un.org/unpd/wpp/publications/files/key_findings_wpp_2015.pdf">around</a> one billion by 2050. Around two-thirds of their lands <a href="http://www.landmarkmap.org/map/#x=-102.46&y=13.47&l=3&a=percentLands">are not</a> farms but forests and rangelands critical to their livelihoods.</p>
<p>Unfortunately, while the ruling is legally binding, the court will have to work hard to ensure compliance. The Kenyan Government is <a href="https://www.standardmedia.co.ke/article/2000037356/cheers-turn-to-tears-for-endorois-waiting-for-land/?pageNo=2">yet to</a> implement a 2009 quasi-judicial ruling by the African Commission on a similar issue. No doubt this non-compliance encouraged the commission to forward the case to the African Court.</p>
<h2>Linking land rights and conservation</h2>
<p>The court made some <a href="http://en.african-court.org/images/Cases/Judgment/Application%20006-2012%20-%20African%20Commission%20on%20Human%20and%20Peoples%E2%80%99%20Rights%20v.%20the%20Republic%20of%20Kenya..pdf">key observations in its ruling</a>. These included:</p>
<ul>
<li><p>The profound attachment that Ogiek hunter-gatherers have to their environment and the way in which this shapes every aspect of their society, irrespective of modernising lifestyles.</p></li>
<li><p>Their long history of subjugation and marginalisation, including denial of land rights that have been granted to stronger tribes. The first major forcible evictions of the Mau Ogiek <a href="http://www.forestpeoples.org/sites/fpp/files/publication/2010/10/kenyaeng.pdf">date back</a> to the 1910s under the British colonial government.</p></li>
</ul>
<p>The court also concluded that evicting the Ogiek is neither</p>
<blockquote>
<p>[necessary] nor proportionate to achieve the purported [government] justification of preserving the natural ecosystem of the Mau Forest. </p>
</blockquote>
<p>On the contrary, the court found evidence, that the Kenyan government was responsible for much of the environmental destruction. This included taking land for private settlement (including for politically powerful elites <a href="http://www.nation.co.ke/news/1056-818058-il62ofz/index.html">such as</a> former President Moi) and losses through “ill-advised <a href="https://news.mongabay.com/2016/09/youth-women-indigenous-group-pay-the-price-of-logging-in-kenya/">logging</a> concessions”. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/173396/original/file-20170612-7026-1x1k10a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/173396/original/file-20170612-7026-1x1k10a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/173396/original/file-20170612-7026-1x1k10a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/173396/original/file-20170612-7026-1x1k10a.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/173396/original/file-20170612-7026-1x1k10a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/173396/original/file-20170612-7026-1x1k10a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/173396/original/file-20170612-7026-1x1k10a.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">
<figcaption>
<span class="caption">A man from the Ogiek community harvests honey.</span>
<span class="attribution"><span class="source">Reuters/Katy Migiro</span></span>
</figcaption>
</figure>
<p>The court recognised that the intact forest is infinitely more valuable to forest people than a cleared forest. The Ogiek’s founding traditional beekeeping culture requires complex natural forests to survive, and virtually every ritual and organisational norm is borne from the forest’s existence. “We lose the forest, we lose our society” is a routine refrain among Kenya’s modern forest peoples.</p>
<p>The court’s recognition of this is crucial. The government of Kenya pinned its defence on firstly that Ogiek were no longer solely dependent on hunting and gathering, and secondly that the need to evict them was in the public interest of saving natural forests. </p>
<p>The judges found little to suggest the public interest would be served by this strategy.</p>
<h2>Reaping the ruling’s rewards</h2>
<p>Who will benefit from this judgement? The answer is: a wide-range of people, as well as policies and institutions.</p>
<p>The first is the court itself. It has demonstrated its autonomy in a continent where judicial independence remains shaky in many states.</p>
<p>Secondly, all indigenous forest peoples in Kenya will find it easier to advance their own claims for recognition as owners of presently classified “government” forests. Around 135,000 members of forest peoples are directly affected - these include the Elgon Ogiek and <a href="http://uk.reuters.com/article/uk-kenya-forests-indigenous-feature-idUKKCN0YA023">Sengwer</a> communities. </p>
<p>The case has also given indigenous peoples throughout Africa resounding legal recognition that they exist and are due the support of international law.</p>
<p>And restitution in general will be advanced in Kenya. This is <a href="http://kenyalaw.org/kl/fileadmin/pdfdownloads/AmendmentActs/2016/LandLaws_Amendment_Act_28of2016.pdf">promised in law</a> as one of the remedies for historical land injustices, but it’s never applied.</p>
<p>All <a href="https://books.google.co.ke/books?id=k6nfDQAAQBAJ&pg=PA475&lpg=PA475&dq=Liz+alden+wily+in+graziadei+and+smith+eds+comparative+property+law&source=bl&ots=XtJ_lJnjkV&sig=RBAK7gjF2h9WprGVuWIeG6Tq0LM&hl=en&sa=X&redir_esc=y#v=onepage&q=Liz%20alden%20wily%20in%20graziadei%20and%20smith%20eds%20comparative%20property%20law&f=false">customary landowners</a> around the continent can look to the judgement as a source of support for legal recognition of their tenure as lawful possession. While ten or so states <a href="http://www.landmarkmap.org/map/#x=-102.46&y=5.01&l=3&a=landTenure">have</a> taken this position since the 1990s, it remains weak or absent in 40. </p>
<p>The judgement will also boost conservation strategies that look to communities to conserve vulnerable protected areas. The right to evict traditional owners in the name of conservation has been dealt a body blow.</p>
<h2>Implementing the judgement</h2>
<p>This is a tricky question. The court ruled that reparations will be decided in a separate decision once it has heard additional submissions from both parties. </p>
<p>The Ogiek were clear on their asks; compensation for the hardships and losses they have endured, guarantees of non-repetition of evictions and denial of their land, cultural and development rights without their consent, and most of all, restitution of their lands and the right to occupy and conserve them. </p>
<p>While the government of Kenya can be expected to protest each demand, and compromises will be made, the court has set the bar high on all counts by establishing that violations have occurred in all these areas and must be remedied.</p>
<p>Moreover, Ogiek asks have the support of Kenya’s new constitution which <a href="http://www.klrc.go.ke/index.php/constitution-of-kenya/117-chapter-five-land-and-environment/part-1-land/230-63-community-land">provides</a> for community lands as a lawful category of property. This includes “the ancestral lands and lands traditionally occupied by hunter-gatherer communities”.</p>
<p>Nevertheless, as ever, on the continent, the surest route to compliance will be pressure from citizens. It is in the interests of at least 18 million customary landholders in Kenya to apply this pressure.</p><img src="https://counter.theconversation.com/content/79303/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Liz Alden Wily is a Fellow of the Katiba Institute</span></em></p>The African court has demonstrated its autonomy in a continent where judicial independence remains shaky in many states.Liz Alden Wily, Researcher/Advocate on Customary Land Rights, Fellow at Van Vollenhoven Institute for Law, Governance and Society, Leiden UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/553322016-03-14T09:56:09Z2016-03-14T09:56:09ZIs it possible to get 15% of your calories from sugar and still be healthy?<figure><img src="https://images.theconversation.com/files/113611/original/image-20160302-25891-1j4yhlz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The Hadza get 15% of their calories from honey.</span> <span class="attribution"><a class="source" href="http://www.flickr.com/photos/kiwiexplorer/3224606276/">kiwiexplorer/flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>It would be fair to say that most of us lead a life far removed from our hunter-gatherer days. Consequently, studies into remote tribes, and the effect of their diet and foraging behaviour, have been used to try to understand the effect of our modern lifestyle on conditions such as obesity and type 2 diabetes. </p>
<p>Members of the Hadza, a hunter-gatherer community from Tanzania, obtain <a href="http://www.ncbi.nlm.nih.gov/pubmed/24746602">15% of their calories</a> from honey. They have a relatively long <a href="http://www.ncbi.nlm.nih.gov/pubmed/1443092">life expectancy</a> and little to no incidence of metabolic disease. </p>
<p>Research <a href="https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/470179/Sugar_reduction_The_evidence_for_action.pdf">suggests</a> that people in the UK consume an almost equivalent amount of sugar (<a href="https://publichealthmatters.blog.gov.uk/2015/07/17/expert-interview-new-sugar-recommendations">guidelines</a> recommend no more than 5%) yet there is an obesity epidemic, with a comparable increase in the number of people developing type 2 diabetes. So, are the guidelines wrong? Or are we simply consuming the wrong kind of sugar? If we replaced all table sugar with honey would we see a dramatic decrease in the number of people who develop type 2 diabetes? </p>
<p>Perhaps predictably, it’s not that simple. A hunter-gatherer tribe will spend a large proportion of their time, well, hunting and gathering – a less common urban activity these days. A diet containing such high levels of honey is going to have a very different effect on a population with higher physical activity. We would definitely need to move a lot more to earn that 15%. Although obesity is an <a href="https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/296290/obesity-map-full-hi-res.pdf">incredibly complex</a> condition (as the graphic below shows), the benefits of exercise on physical (and mental) <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3838691/">well-being</a> can’t be argued.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/114646/original/image-20160310-26283-zxzvd2.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/114646/original/image-20160310-26283-zxzvd2.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/114646/original/image-20160310-26283-zxzvd2.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/114646/original/image-20160310-26283-zxzvd2.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/114646/original/image-20160310-26283-zxzvd2.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/114646/original/image-20160310-26283-zxzvd2.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=504&fit=crop&dpr=1 754w, https://images.theconversation.com/files/114646/original/image-20160310-26283-zxzvd2.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=504&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/114646/original/image-20160310-26283-zxzvd2.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=504&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Screen Shot at.</span>
<span class="attribution"><a class="source" href="https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/296290/obesity-map-full-hi-res.pdf">Government Office for Science</a></span>
</figcaption>
</figure>
<h2>Isn’t honey sugar anyway?</h2>
<p>Although honey (largely fructose and glucose) and sugar (sucrose) have a similar calorie content, honey is <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3399220/">reported</a> to have as many as 180 individual components. These include flavonoids, vitamins and organic acids, which may all contribute to the sticky stuff’s alleged beneficial effects. Honey also has antifungal, antimicrobial and anti-inflammatory properties. And it has been proposed to reduce the risk of <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3758027/">heart disease</a> and decrease markers of liver damage. It has even been reported to <a href="http://www.ajol.info/index.php/ajbr/article/view/50706">reduce blood glucose</a> levels. </p>
<p>Evidence of the latter benefit, however, is far from conclusive. Honey seems to reduce blood glucose in <a href="http://www.sciencedirect.com/science/article/pii/S0167527309010699">diabetic animals</a> in the lab, but studies on humans have been less convincing. Some studies have demonstrated a <a href="http://www.ncbi.nlm.nih.gov/pubmed/18454257">glucose lowering</a> effect of honey, others have shown an <a href="http://www.ncbi.nlm.nih.gov/pubmed/19817641">increase</a> in average blood glucose, while others have reported no noticeable effect at all. But this may be down to poor study design, so it may still be worth investigating. A further limitation is that the majority of studies only look at the short-term effects of honey while long-term effects could be more enlightening, particularly in the case of the Hadza tribe. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/114487/original/image-20160309-13704-1kt9hjq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/114487/original/image-20160309-13704-1kt9hjq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=449&fit=crop&dpr=1 600w, https://images.theconversation.com/files/114487/original/image-20160309-13704-1kt9hjq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=449&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/114487/original/image-20160309-13704-1kt9hjq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=449&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/114487/original/image-20160309-13704-1kt9hjq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=564&fit=crop&dpr=1 754w, https://images.theconversation.com/files/114487/original/image-20160309-13704-1kt9hjq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=564&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/114487/original/image-20160309-13704-1kt9hjq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=564&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Honey is mainly fructose and glucose.</span>
<span class="attribution"><a class="source" href="http://www.shutterstock.com/cat.mhtml?lang=en&language=en&ref_site=photo&search_source=search_form&version=llv1&anyorall=all&safesearch=1&use_local_boost=1&autocomplete_id=&search_tracking_id=ti0h2gF-OOWkwe2fCpxyow&searchterm=honey&show_color_wheel=1&orient=&commercial_ok=&media_type=images&search_cat=&searchtermx=&photographer_name=&people_gender=&people_age=&people_ethnicity=&people_number=&color=&page=1&inline=177189773">www.shutterstock.com</a></span>
</figcaption>
</figure>
<h2>Gut feeling?</h2>
<p>As the true effects of honey on blood glucose are still to be determined, it is hard to suggest a potential mechanism of action. That being said, <a href="https://theconversation.com/explainer-what-is-the-gut-microbiota-and-how-does-it-affect-mind-and-body-40536">gut microbiota</a> offer a fascinating angle to explore.</p>
<p>Once overlooked, gut microbiota have now been shown to influence a range of <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4036413/">immunological</a> and <a href="http://diabetes.diabetesjournals.org/content/62/10/3341.full">metabolic</a> disorders. We rely on our gut bacteria to obtain energy from food that would otherwise pass through us – <a href="http://www.nature.com/news/2006/060522/full/news060522-19.html">around 10%</a> of the calories we consume. Researchers have even shown that <a href="http://www.nature.com/nature/journal/v444/n7122/abs/nature05414.html">transplanting gut bacteria</a> from obese mice to lean can cause weight gain in the latter. </p>
<p>In 2013, <a href="http://www.nature.com/ncomms/2014/140415/ncomms4654/pdf/ncomms4654.pdf">researchers identified</a> key differences between the gut microbiota of members of the Hadza tribe, compared with a group of city-living Italian adults. It’s perhaps unsurprising that such different diets and lifestyles are mirrored in the gut flora, however, the specific changes are intriguing. The intestines of the Hadza people tested were almost completely lacking in <em>Bifidobacterium</em>, the probiotic bacteria that we associate with good intestinal health. </p>
<p>Incidentally, honey has been shown to increase <em>Bifidobacterium</em> and subsequently improve glucose tolerance in mice. So, does the lack of <em>Bifidobacterium</em> in the Hadza gut mean the idea of honey lowering blood glucose is complete nonsense? Again, it’s more complicated than that.</p>
<p>When it comes to gut bacteria, numbers aren’t always important. A small population of bacteria can still have a large effect on health. Alternatively, the probiotic role may be carried out by different bacteria, which are thriving on the Hadza diet where <em>Bifidobacterium</em> are not. </p>
<p>Nearly all nutritional research comes with a disclaimer: every body is unique. We respond differently to specific foodstuffs eaten at different times for both genetic and environmental reasons. There are so many variables that it’s hard to determine the effect of one single thing. </p>
<h2>Honey for breakfast, lunch and dinner?</h2>
<p>But should we be cutting back the sugar and eating more honey? Balance is key and honey is not calorie-free. Excessive honey, if not balanced with energy output, will cause weight gain. There may be more benefits in having honey than sugar because of the additional nutrients and enzymes it contains, but that doesn’t mean it should be consumed in excess (and keep an eye out for the effects of “<a href="http://modernfarmer.com/2014/09/strange-history-hallucinogenic-mad-honey/">mad honey</a>”). </p>
<p>When it comes to our diets, we often look for a quick fix and clear-cut advice – so we run the risk of interpreting results of small trials to fit our preconceived beliefs or desires. Honey cake anyone? Uncertainty and scientific research go hand in hand, and nutritional research is definitely not an exception. So I tend to follow my mother’s rule: everything in moderation.</p><img src="https://counter.theconversation.com/content/55332/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Claire Marriott 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>The Hadza hunter-gatherer community get 15% of their calories from honey. If they can live on a high-sugar diet, why can’t we?Claire Marriott, Senior lecturer, University of BrightonLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/533972016-01-20T18:02:45Z2016-01-20T18:02:45ZFinding a hunter-gatherer massacre scene that may change history of human warfare<figure><img src="https://images.theconversation.com/files/108598/original/image-20160119-29754-f3uojn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Skull of a man with multiple lesions on the side, probably caused by a club.</span> <span class="attribution"><span class="source"> Image by Marta Mirazon Lahr, enhanced by Fabio Lahr</span></span></figcaption></figure><p>The area surrounding <a href="http://whc.unesco.org/en/list/801">Lake Turkana in Kenya</a> was lush and fertile 10,000 years ago, with thousands of animals – including elephants, giraffes and zebras – roaming around alongside groups of hunter gatherers. But it also had a dark side. We have discovered the oldest known case of violence between two groups of hunter gatherers took place there, with ten excavated skeletons showing evidence of having been killed with both sharp and blunt weapons. </p>
<p>The findings, <a href="http://nature.com/articles/doi:10.1038/nature16477">published in Nature</a>, are important because they challenge our understanding of the roots of conflict and suggest warfare may have a much older history than many researchers believe.</p>
<h2>Shocking finding</h2>
<p>Our journey started in 2012, when Pedro Ebeya, one of our Turkana field assistants, reported seeing fragments of human bones on the surface at Nataruk. Located just south of Lake Turkana, Nataruk is today a barren desert, but 10,000 years ago was a temporary camp set up by a band of hunter-gatherers next to a lagoon. I led a team of researchers, as part of the <a href="http://in-africa.org/">In-Africa project</a>, which has been working in the area since 2009. We excavated the remains of 27 people – six young children, one teenager and 20 adults. Twelve of these – both men and women – were found as they had died, unburied, and later covered by the shallow water of the lagoon. </p>
<p>Ten of the 12 skeletons show lesions caused by violence to the parts of the body most commonly involved in cases of violence. These include one where the projectile was still embedded in the side of the skull; two cases of sharp-force trauma to the neck; seven cases of blunt and/or sharp-force trauma to the head; two cases of blunt-force trauma to the knees and one to the ribs. There were also two cases of fractures to the hands, possibly caused while parrying a blow.</p>
<p>There must have at least three types of weapons involved in these murders – projectiles (stoned-tipped as well as sharpened arrows), something similar to a club, and something close to a wooden handle with hafted sharp-stone blades that caused deep cuts. Two individuals have no lesions in the preserved parts of the skeleton, but the position of their hands suggests they may have been bound, including a young woman who was heavily pregnant at the time.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/108600/original/image-20160119-29772-k5icgn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/108600/original/image-20160119-29772-k5icgn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=480&fit=crop&dpr=1 600w, https://images.theconversation.com/files/108600/original/image-20160119-29772-k5icgn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=480&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/108600/original/image-20160119-29772-k5icgn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=480&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/108600/original/image-20160119-29772-k5icgn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=604&fit=crop&dpr=1 754w, https://images.theconversation.com/files/108600/original/image-20160119-29772-k5icgn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=604&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/108600/original/image-20160119-29772-k5icgn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=604&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Me and my colleague, Justus Edung, during the excavations.</span>
<span class="attribution"><span class="source">Credit: Robert Foley</span></span>
</figcaption>
</figure>
<p>We dated the remains and the site to between 10,500 and 9,500 years ago, making them the earliest scientifically dated case of a conflict between two groups of hunter-gatherers. Stones in the weapons include obsidian, a rare stone in the Nataruk area, suggesting the attackers came from a different place.</p>
<h2>The (pre)history of warfare</h2>
<p>Today we think of warfare, or inter-group conflict, as something that happens when one group of people wants the territory, resources or power held by another. But prehistoric societies were usually small groups of nomads moving from place to place – meaning they didn’t own land or have significant possessions. They typically <a href="https://theconversation.com/why-our-ancestors-were-more-gender-equal-than-us-41902">didn’t have strong social hierarchies</a> either. Therefore, <a href="https://www.sciencemag.org/content/341/6143/270.full">many scholars have argued</a> that warfare must have emerged <a href="https://theconversation.com/why-we-think-the-very-first-farmers-were-small-groups-with-property-rights-50319">after farming</a> and more complex political systems arose.</p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/108601/original/image-20160119-29762-1wkvphe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/108601/original/image-20160119-29762-1wkvphe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=1465&fit=crop&dpr=1 600w, https://images.theconversation.com/files/108601/original/image-20160119-29762-1wkvphe.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=1465&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/108601/original/image-20160119-29762-1wkvphe.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=1465&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/108601/original/image-20160119-29762-1wkvphe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1841&fit=crop&dpr=1 754w, https://images.theconversation.com/files/108601/original/image-20160119-29762-1wkvphe.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1841&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/108601/original/image-20160119-29762-1wkvphe.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1841&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Man with an obsidian bladelet embedded into the left side of his skull, and a projectile lesion (possibly of a sharpened arrow shaft) on the right side of the skull.</span>
<span class="attribution"><span class="source">Marta Mirazon Lahr</span></span>
</figcaption>
</figure>
<p>Naturuk therefore challenges our views about what the causes of conflict are. It is possible that human prehistoric societies simply responded antagonistically to chance encounters with another group. But this is not what seems to have happened at Nataruk. The group which attacked was carrying weapons that would not normally be carried while hunting and fishing. In addition, the lesions show that clubs of at least two sizes were used, making it likely that more than one of the attackers were carrying them. </p>
<p>The fact that the attack combined long-distance weapons such as arrows and close-proximity weaponry such as clubs suggests they planned the attack. Also, there are other, but isolated, examples of violent trauma in this area from this period in time – one discovered in the 1970s about 20km north of Nataruk, and two discovered by our project at a nearby site. All three involved projectiles, one of the hallmarks of inter-group conflict. Two of the projectiles found embedded in the bones at Nataruk and in two of the other cases were made of obsidian. This tells us that such attacks happened multiple times, and were part of the life of the hunter-gatherer communities at the time.</p>
<p>So why were the people of Nataruk attacked? We have to conclude that they had valuable resources that were worth fighting for – water, meat, fish, nuts, or indeed women and children. This suggests that two of the conditions associated with warfare among settled societies – territory and resources – were probably common among these hunter-gatherers, and that we have underestimated their role so far.</p>
<p>Evolution is about survival, and our species is no different from others in this respect. The injuries suffered by the people of Nataruk are merciless and shocking, but no different from those suffered in wars throughout much of our history – sadly even today. It may be human nature, but we should not forget that <a href="https://www.newscientist.com/article/dn10750-why-altruism-paid-off-for-our-ancestors/">extraordinary acts of altruism</a>, compassion and caring are also unique parts of who we are.</p><img src="https://counter.theconversation.com/content/53397/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Marta Mirazon Lahr receives funding from the European Research Council.</span></em></p>Why hunter gatherers weren’t as peaceful as you may think.Marta Mirazon Lahr, Reader in Human Evolutionary Biology & Director of the Duckworth Collection, University of CambridgeLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/269452014-05-20T14:32:40Z2014-05-20T14:32:40ZCaveman instincts may explain our belief in gods and ghosts<figure><img src="https://images.theconversation.com/files/49000/original/x3xkm622-1400582645.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Does mankind's religious instinct date back to prehistoric times?</span> <span class="attribution"><a class="source" href="http://www.shutterstock.com/pic-110802431/stock-photo-ancient-people-against-the-evening-landscape.html?src=aD1Iiqd1l6yCdOdYkSD9gA-1-70">iurri</a></span></figcaption></figure><p>Notions of gods arise in all human societies, from all powerful and all-knowing deities to simple forest spirits. <a href="http://books.google.co.uk/books/about/The_Naturalness_of_Religious_Ideas.html?id=5jkhjMvYpa4C&redir_esc=y">A recent method</a> of examining religious thought and behaviour links their ubiquity and the similarity of our beliefs to the ways in which human mental processes were adapted for survival in prehistoric times. </p>
<p>It rests on a <a href="http://ruccs.rutgers.edu/%7Ealeslie/images/publications/Leslie%201994b.pdf">couple of observations about human psychology</a>. First, when an event happens, we tend to assume that a living thing caused it. In other words, we assume agency behind that event. If you think of the sorts of events that might have happened in prehistoric times, it’s easy to see why a bias towards agency would be useful. A rustling of a bush or the snapping of a twig could be due to wind. But far better to assume it’s a lion and run away. </p>
<p>The survivors who had this tendency to more readily ascribe agency to an event passed their genes down the generations, increasingly hard-wiring this way of making snap decisions into the brain. This is not something that people need to learn. It occurs quickly and automatically. </p>
<h2>Empathic tendencies</h2>
<p>The second trait is about how we view others. While living together in a tribe would have had many advantages for survival in prehistoric times, getting along with everyone would not always have been easy. Comprehending others’ behaviour requires you to understand their thoughts and beliefs, especially where these may be incorrect due to someone not knowing the full facts of a situation. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/49005/original/r8hnk29y-1400583091.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/49005/original/r8hnk29y-1400583091.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/49005/original/r8hnk29y-1400583091.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=300&fit=crop&dpr=1 600w, https://images.theconversation.com/files/49005/original/r8hnk29y-1400583091.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=300&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/49005/original/r8hnk29y-1400583091.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=300&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/49005/original/r8hnk29y-1400583091.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=377&fit=crop&dpr=1 754w, https://images.theconversation.com/files/49005/original/r8hnk29y-1400583091.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=377&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/49005/original/r8hnk29y-1400583091.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=377&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The prehistoric posse.</span>
<span class="attribution"><a class="source" href="http://www.shutterstock.com/pic-152290322/stock-photo-illustrated-silhouettes-of-cavemen-hunters-on-patrol.html?src=aD1Iiqd1l6yCdOdYkSD9gA-1-75">Robert Adrian Hillman</a></span>
</figcaption>
</figure>
<p>This is known as “theory of mind”. This idea says that we automatically assume that there are reasons behind others’ behaviour which we try to work out in order to better understand why they behave the way they do. Not having this ability <a href="http://autismtruths.org/pdf/3.%20Does%20the%20autistic%20child%20have%20a%20theory%20of%20mind_SBC.pdf">has been proposed</a> to underlie developmental disorders such as autism.</p>
<p>You may be wondering what these two hard-wired processes have to do with belief in gods. Imagine a pebble falling in the back of a cave. Our agency device tells us that someone caused that to happen. With nothing in evidence, could it be an invisible creature or a spirit? If so, why would it be sneaking around? To find out secrets about us or to discover if we are good or bad people? </p>
<p>Another example might be a volcanic eruption. In the absence of geological knowledge, our tribal ancestors’ agency system would have ascribed this event to a person – but one that surely has superhuman ability. And why would they want to cause such destruction? Perhaps the eruption signified a punishment, perhaps because the tribe had not acted in accordance with the being’s wishes. </p>
<h2>Of ghosts and gods</h2>
<p>These two very simplistic examples should help illustrate how these hard-wired mechanisms could lead to the beginnings of a belief in gods, as well as ghosts and other supernatural creatures. Our ancestors would have drawn conclusions about supernatural occurrences by fitting together these instincts towards agency and the theory of mind. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/48925/original/2knn873v-1400518465.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/48925/original/2knn873v-1400518465.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/48925/original/2knn873v-1400518465.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/48925/original/2knn873v-1400518465.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/48925/original/2knn873v-1400518465.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/48925/original/2knn873v-1400518465.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/48925/original/2knn873v-1400518465.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/48925/original/2knn873v-1400518465.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">Are ghosts just part of human survival function?</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/jeffkrause/5772943082/in/photolist-9N8QRq-9BV8JD-4z7WBo-aj81YJ-79UZDg-dZzHu8-8kSEQJ-aCJXQH-reFFA-6deavc-mZSgY5-jqbXHS-6MmBWr-jCD33M-itJbUY-8MzECa-fy3c8J-7gZAG9-igBJMm-334iz8-hRg7nc-4zM8QH-d34hh3-zistE-59MMoQ-adRyKt-7vBhDe-33i3-6hATVa-agKkxD-bqvkAA-7o9w7j-8mQqhr-gTjSMV-jA1oKs-2bY1Vj-fhCPdC-mKEQte-dyzpKp-wUgAp-nzJhAR-8PpEAR-2kxD3w-56LfTG-m5fw-5Fwq5S-d34Dc7-LuNtx-7AfiNW-3hHnhM">Jeff Krause</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>This even applies to the Abrahamic, all-knowing, all powerful god. He may seem very inhuman at first glance, but <a href="http://www.wjh.harvard.edu/%7Elds/readinggroup/barrett1996.pdf">it has been shown</a> that we reason about Him in a very human way. For example we depict Him helping one person before moving to the other side of the world to help someone else. Hard-wired reasoning processes helps explain how religious ideas are so durable, spreading across continents and down through generations. </p>
<p>Both these and other ancient instincts appear to be in evidence from observations of children. Very young children seem to show very accurate understanding of physical laws. For example they know that two solid objects cannot merge into one or that horses do not have metal gears inside them. <a href="http://fitelson.org/woodward/baillargeon.pdf">Developmental psychologists have suggested</a> that children are intuitive biologists, physicists and – using theory of mind – psychologists.</p>
<h2>Sumus rosaceae!</h2>
<p>Concepts which violate these intuitive understandings <a href="http://strathprints.strath.ac.uk/25716/">seem to be</a> more memorable than others. A rose that whispers in Latin violates an intuitive understanding that plants do not have minds or mouths and therefore cannot whisper in an ancient language – or any language for that matter.</p>
<p>It may be that violating an intuitive concept draws special attention and interest and therefore helps embed the idea in memory. Many religious stories contain concepts that seem to violate this special kind of intuition, such as a man walking on water or a burning bush that talks. These tales take advantage of this feature of memory to successfully propagate themselves and resist being forgotten.</p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/48924/original/tpwhp45f-1400518190.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/48924/original/tpwhp45f-1400518190.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=772&fit=crop&dpr=1 600w, https://images.theconversation.com/files/48924/original/tpwhp45f-1400518190.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=772&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/48924/original/tpwhp45f-1400518190.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=772&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/48924/original/tpwhp45f-1400518190.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=971&fit=crop&dpr=1 754w, https://images.theconversation.com/files/48924/original/tpwhp45f-1400518190.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=971&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/48924/original/tpwhp45f-1400518190.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=971&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Got a cup of water?</span>
<span class="attribution"><a class="source" href="http://commons.wikimedia.org/wiki/File:Bourdon,_Sébastien_-_Burning_bush.jpg">Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>Putting these ideas together is one way of explaining religious thought and behaviour. You could go further and suggest that, if these ideas are correct, religion is merely a by-product of mental processes operating in error. </p>
<p>But this assumes that religious/supernatural experiences are not true. If the human mind was to truly experience a god, then the theories of agency and mind and our memory for the counterintuitive would help us make sense of it. If that were to happen, the conclusions would not be in error at all. </p>
<p><em>Dr Kelly will be elaborating on these ideas at a</em> <em><a href="http://www.strath.ac.uk/events/campuscalendar/event_title_798613_en.html">lecture in Glasgow</a></em> <em>on the evening of Thursday May 22.</em></p><img src="https://counter.theconversation.com/content/26945/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Steve Kelly 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>Notions of gods arise in all human societies, from all powerful and all-knowing deities to simple forest spirits. A recent method of examining religious thought and behaviour links their ubiquity and the…Steve Kelly, Senior Lecturer, University of Strathclyde Licensed as Creative Commons – attribution, no derivatives.