tag:theconversation.com,2011:/africa/topics/pyramids-26137/articlesPyramids – The Conversation2023-02-16T14:36:33Ztag:theconversation.com,2011:article/1991932023-02-16T14:36:33Z2023-02-16T14:36:33ZFour ways that fossils are part of everyday life<figure><img src="https://images.theconversation.com/files/508852/original/file-20230208-25-fiytrr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The building blocks of the Giza pyramids contain trillions of fossilised remains of an ocean-dwelling organism called foraminifera.</span> <span class="attribution"><span class="source">Sui Xiankai/Xinhua via Getty Images</span></span></figcaption></figure><p>South Africa boasts some of the best fossil records on Earth. Fossils are found in strata and rocks in many parts of the country. Some are billions of years old. </p>
<p>There are microfossils <a href="https://www.sciencedirect.com/science/article/pii/S0923250803002018">dating back to the Archaean epoch</a>, between 3.5 billion and 3.3 billion years ago, in the Barberton Greenstone Belt in the Mpumalanga province. The fossils of now extinct invertebrates that lived around 444 million years ago <a href="https://pubs.geoscienceworld.org/jgs/article/174/1/1/317725/The-late-Ordovician-Soom-Shale-Lagerstatte-an">have been found</a> in the Western Cape province. So, too, have fossils of large animals like sivatheres (giraffids) and <a href="https://theconversation.com/sabretooth-cats-hunted-on-south-africas-coast-5-million-years-ago-this-old-one-was-in-pain-192200">sabretooth cats</a>, 5 million years old. The country’s fossils also contain an <a href="https://www.livescience.com/south-african-fossils-human-evolution">exceptional record of human ancestry</a>, mapping our evolutionary history through time.</p>
<p>But fossils aren’t just pieces of the past that allow scientists to look backwards. They also provide geologists with important information about what future environments may look like, play a role in policy decision-making and have become a part of our daily lives – often without us realising it.</p>
<h2>Fossils in man-made structures</h2>
<p>Fossils have provided humans with building blocks in architectural structures for centuries. The pyramids of Giza in Egypt are around 4,500 years old; the stones they are built from are millions of years old – 56 million to 34 million years, to be more precise. The building blocks of the pyramids contain trillions of fossilised remains of an ocean-dwelling organism called <a href="https://ucmp.berkeley.edu/science/fieldnotes/casazza_0711.php">foraminifera</a>.</p>
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Read more:
<a href="https://theconversation.com/phosphorites-mineral-rich-rocks-offer-insight-into-ancient-namibian-ecosystems-169773">Phosphorites: mineral-rich rocks offer insight into ancient Namibian ecosystems</a>
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<p>These organisms are still found in the oceans today. When they die, their shells become preserved and fossilise in sediment; this hardens into rock over a very long period of time. The stone from which the pyramids are constructed is called nummulitic limestone – a name derived from the foraminifera species it’s made of, <em>Nummulites gizehensis</em>. </p>
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<img alt="" src="https://images.theconversation.com/files/509880/original/file-20230213-27-1x0dxi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/509880/original/file-20230213-27-1x0dxi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=477&fit=crop&dpr=1 600w, https://images.theconversation.com/files/509880/original/file-20230213-27-1x0dxi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=477&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/509880/original/file-20230213-27-1x0dxi.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=477&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/509880/original/file-20230213-27-1x0dxi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=599&fit=crop&dpr=1 754w, https://images.theconversation.com/files/509880/original/file-20230213-27-1x0dxi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=599&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/509880/original/file-20230213-27-1x0dxi.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=599&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Close-up of an ammonite fossil preserved in marble paving in Urbino, Italy.</span>
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<p>And it’s not just ancient civilisations that used fossils for building. Many modern buildings and structures in North America and Europe are made from building or paving stones containing fossils. These building stones were quarried from fossiliferous rock layers dated to the Jurassic or Cretaceous periods when dinosaurs still roamed the Earth. </p>
<p>Even in South Africa, some imported building stones contain fossils. The Bishop Gray Monument on St George’s Square in Cape Town, for instance, contains marble with <a href="https://artefacts.co.za/main/Buildings/bldgframes_mob.php?bldgid=3286">Mesozoic-aged cephalopod fossils</a> that date back more than 65 million years. </p>
<h2>Fossils as indicators of economic resources</h2>
<p>We use minerals, petroleum, oil and natural gas daily. These geologic resources need to be discovered and evaluated before extraction. In regions where fossils occur, geologists use them to date rocks and sediments to find and evaluate these resources. </p>
<p>Certain fossils are useful in that they provide an age to sediments or rocks; the organisms or animals that formed the fossils lived only during a narrow time period in Earth’s history. Some rock strata house fossils that lived during an age and in an environment that can be linked to modern economic resources. </p>
<p>This is important in finding where certain rock units are that can point to economic reserves. Fossils, particularly microfossils – the remains of very small to microscopic-sized animals or organisms – have been used in mineral, petroleum and oil exploration globally. In South Africa, microfossils found in the Karoo Basin in the centre of the country, the <a href="https://journals.co.za/doi/pdf/10.10520/AJA00382353_3806">south coast</a> and offshore of the <a href="http://etd.uwc.ac.za/xmlui/handle/11394/7594">west coast</a> have all been used in oil, mineral and petroleum exploration. </p>
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Read more:
<a href="https://theconversation.com/the-study-of-tiny-fossils-reminds-us-that-museums-are-key-to-advancing-science-146121">The study of tiny fossils reminds us that museums are key to advancing science</a>
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<h2>Fossil fuels</h2>
<p>When animals, organisms and plants die in certain environments and become buried under thick layers of sediment, heat and pressure transform their remains in such a way that they become part of petroleum, natural gas or coal.</p>
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<img alt="" src="https://images.theconversation.com/files/509887/original/file-20230213-5048-6fmtik.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/509887/original/file-20230213-5048-6fmtik.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=293&fit=crop&dpr=1 600w, https://images.theconversation.com/files/509887/original/file-20230213-5048-6fmtik.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=293&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/509887/original/file-20230213-5048-6fmtik.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=293&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/509887/original/file-20230213-5048-6fmtik.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=368&fit=crop&dpr=1 754w, https://images.theconversation.com/files/509887/original/file-20230213-5048-6fmtik.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=368&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/509887/original/file-20230213-5048-6fmtik.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=368&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Pieces of coal (North-West University Geology Collection)</span>
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<p>For the past 150 years vast amounts of these reserves have been extracted to provide a major source of the world’s energy needs. Fossil fuels have played an immeasurable role in powering <a href="https://www.oecd.org/newsroom/support-for-fossil-fuels-almost-doubled-in-2021-slowing-progress-toward-international-climate-goals-according-to-new-analysis-from-oecd-and-iea.htm">the global economy</a>. They generate electricity, keep vehicles moving and keep industry running. Today it is estimated that <a href="https://www.energy.gov.za/files/coal_frame.html">nearly 80%</a> of South Africa’s energy needs are met by fossil fuels, particularly coal.</p>
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<a href="https://theconversation.com/why-south-africa-cant-make-a-massive-shift-to-renewables-yet-104734">Why South Africa can't make a massive shift to renewables - yet</a>
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<p>However, fossil fuels are a non-renewable energy source. Burning them contributes to both <a href="https://www.researchgate.net/profile/Athanasios-Drigas/publication/332029427_Climate_Change_101_How_Everyday_Activities_Contribute_to_the_Ever-Growing_Issue/links/5c9b9997a6fdccd4603f1910/Climate-Change-101-How-Everyday-Activities-Contribute-to-the-Ever-Growing-Issue.pdf">climate change</a> and <a href="https://www.nrdc.org/stories/fossil-fuel-air-pollution-kills-one-five-people">health issues</a>. There is an ongoing debate in South Africa, as in most other parts of the world, about how to use more renewable energy rather than relying so heavily on fossil fuels.</p>
<h2>Estimating future environmental changes</h2>
<p>Burning fossil fuels causes environmental harm – but studying fossils helps geologists to <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0054443">reconstruct past environments</a>, offering insights into likely future environmental change. </p>
<p>Geologists or palaeontologists study rocks that contain fossils to understand the environments they once inhabited. They then use this information to estimate how environments, sea levels or the oceans will change with time. An example of this is the <a href="https://www.britannica.com/science/Pliocene-Epoch">Pliocene period</a> (5.3 million to 2.6 million years ago). It is often described as comparable to modern climate change: during the Pliocene, several global geologic events occurred which led to <a href="https://ucmp.berkeley.edu/tertiary/pliocene.php">today’s oceanic configurations</a>.</p>
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<img alt="" src="https://images.theconversation.com/files/509888/original/file-20230213-14-zu6qc3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/509888/original/file-20230213-14-zu6qc3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/509888/original/file-20230213-14-zu6qc3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/509888/original/file-20230213-14-zu6qc3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/509888/original/file-20230213-14-zu6qc3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/509888/original/file-20230213-14-zu6qc3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/509888/original/file-20230213-14-zu6qc3.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">
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<span class="caption">Strata such as this Miocene-Pliocene outcrop containing fossils are studied to determine past environmental and climate conditions.</span>
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<p>But something was missing during the Pliocene – humans. Nonetheless, scientists attempt to model what Earth’s natural responses are to rising carbon dioxide in the atmosphere, in addition to the effects of humans, by studying the Pliocene when carbon dioxide levels were at <a href="https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2019PA003835">similar levels to today</a>.</p><img src="https://counter.theconversation.com/content/199193/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Eugene Bergh receives funding from the National Research Foundation South Africa</span></em></p>Fossils aren’t just pieces of the past that allow scientists to look backwards. They can play a role in modern policy decision-making, too.Eugene Bergh, Senior lecturer, North-West UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1595962021-06-14T15:49:49Z2021-06-14T15:49:49ZSudan’s ‘forgotten’ pyramids risk being buried by shifting sand dunes<figure><img src="https://images.theconversation.com/files/406165/original/file-20210614-47555-wwdvzo.jpg?ixlib=rb-1.1.0&rect=6%2C0%2C4354%2C2197&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Martchan / shutterstock</span></span></figcaption></figure><p>The word “pyramid” is synonymous with Egypt, but it is actually neighbouring Sudan that is home to the world’s largest collection of these spectacular ancient structures.</p>
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<iframe id="noa-web-audio-player" style="border: none" src="https://embed-player.newsoveraudio.com/v4?key=x84olp&id=https://theconversation.com/sudans-forgotten-pyramids-risk-being-buried-by-shifting-sand-dunes-159596&bgColor=F5F5F5&color=D8352A&playColor=D8352A" width="100%" height="110px"></iframe>
<p><em>You can listen to more articles from The Conversation, narrated by Noa, <a href="https://theconversation.com/uk/topics/audio-narrated-99682">here</a>.</em></p>
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<p>Beginning around 2500BC, Sudan’s ancient Nubian civilisation left behind more than 200 pyramids that rise out of the desert across three <a href="http://www.sudarchrs.org.uk">archaeological</a> sites: El Kurru, Jebel Barkal and Meroe, in addition to temples, tombs and royal burial chambers.</p>
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<a href="https://images.theconversation.com/files/406147/original/file-20210614-65156-43ifun.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Map of Sudan with dots" src="https://images.theconversation.com/files/406147/original/file-20210614-65156-43ifun.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/406147/original/file-20210614-65156-43ifun.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=710&fit=crop&dpr=1 600w, https://images.theconversation.com/files/406147/original/file-20210614-65156-43ifun.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=710&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/406147/original/file-20210614-65156-43ifun.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=710&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/406147/original/file-20210614-65156-43ifun.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=892&fit=crop&dpr=1 754w, https://images.theconversation.com/files/406147/original/file-20210614-65156-43ifun.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=892&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/406147/original/file-20210614-65156-43ifun.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=892&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Nubian archaeological sites in modern-day Sudan and Egypt.</span>
<span class="attribution"><a class="source" href="https://www.google.com/maps/d/u/0/viewer?ie=UTF8&hl=en&msa=0&t=h&ll=21.58867450404889%2C35.418475937499984&spn=8.386687%2C5.141599&source=embed&mid=1tzaCtXWcus01krv982rpD6CcMyA&z=5">Google Maps</a></span>
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<p>Despite being smaller than the famous Egyptian pyramids of Giza, <a href="http://www.sudarchrs.org.uk/wp-content/uploads/2019/03/SARS_SN04_Hinkel_opt.pdf">Nubian pyramids</a> are just as magnificent and culturally valuable. They even offer a crowd-free experience for intrepid tourists.</p>
<p>Built of sandstone and granite, the steeply-sloping pyramids contain chapels and burial chambers decorated with illustrations and inscriptions carved in hieroglyphs and Meroitic script celebrating the rulers’ lives in Meroe – a wealthy Nile city and the seat of power of Kush, an ancient kingdom and rival to Egypt.</p>
<p>Located about 220km north of the capital Khartoum, the cultural gem of Meroe is now one of Sudan’s most significant <a href="https://whc.unesco.org/en/list/1336/">Unesco world heritage sites</a>. However a lack of preservation, severe weather conditions and negligent visitors have all taken their toll on its monuments. Back in the 1880s, for instance, the Italian explorer Giuseppe Ferlini <a href="https://www.nytimes.com/2010/05/22/arts/22iht-melik22.html">blew up several pyramids</a> in his search for Kushite treasure, leaving many of the tombs missing their pointy tops. Many more of Sudan’s other pyramids were subsequently plundered and destroyed by looters.</p>
<h2>Shifting sands</h2>
<p>These days sandstorms and shifting sand dunes pose the biggest threat to Sudan’s ancient heritage sites. This phenomenon is nothing new, and was even chronicled thousands of years ago. An inscription found in a temple from the 5th century BC describes a Kushite king giving an order to <a href="http://www.sudarchrs.org.uk/wp-content/uploads/2019/03/SARS_SN16_Munro_opt.pdf">clear out sand from the pathway</a>: </p>
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<p>His Majesty brought a multitude of hands, to wit, men and women as well as royal children and chiefs to carry away the sand; and his Majesty was carrying away sand with his hand(s) himself, at the forefront of the multitude for many days.</p>
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<p>But today the threat has been exacerbated by climate change, which has made the land more arid and sandstorms more frequent. Moving sands can engulf entire houses in rural Sudan, and cover <a href="https://www.tandfonline.com/doi/abs/10.1080/13504509409469874">fields, irrigation canals and riverbanks</a>. </p>
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<a href="https://images.theconversation.com/files/406171/original/file-20210614-102836-1vnwmgk.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Pyramids covered by sand" src="https://images.theconversation.com/files/406171/original/file-20210614-102836-1vnwmgk.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/406171/original/file-20210614-102836-1vnwmgk.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=397&fit=crop&dpr=1 600w, https://images.theconversation.com/files/406171/original/file-20210614-102836-1vnwmgk.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=397&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/406171/original/file-20210614-102836-1vnwmgk.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=397&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/406171/original/file-20210614-102836-1vnwmgk.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=499&fit=crop&dpr=1 754w, https://images.theconversation.com/files/406171/original/file-20210614-102836-1vnwmgk.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=499&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/406171/original/file-20210614-102836-1vnwmgk.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=499&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Sand creeps over a pyramid at the northern royal cemetery of Meroe.</span>
<span class="attribution"><span class="source">Ahmed Mahmoud</span>, <span class="license">Author provided</span></span>
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<p>While some archaeologists believe sand movement helps to <a href="https://thearabweekly.com/egyptologists-uncover-lost-golden-city-buried-under-sand">preserve ancient artefacts from thieves</a>, it is known to be detrimental to excavated sites, reburying them beneath the desert. Sand blown by the wind also <a href="https://research-repository.st-andrews.ac.uk/handle/10023/17889">erodes delicate stonework and sculptures</a>.</p>
<h2>Fighting back against desertification</h2>
<p>The best way to combat sand movement and desertification is to increase the vegetation cover, and one ambitious African-led reforestation project is leading the way.</p>
<p>Bringing together more than 20 nations, the <a href="https://www.greatgreenwall.org/about-great-green-wall">Great Green Wall</a> is a multi-billion dollar movement to stop the spread of the Sahara Desert by restoring 100 million hectares of land across the continent from Senegal in west Africa to Djibouti in the east. The intention is to cultivate the largest living barrier of trees and plants on the planet, with Sudan having the longest stretch of the “wall”.</p>
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<a href="https://images.theconversation.com/files/398749/original/file-20210504-13-1g7ruou.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Map of Africa with green line and shaded orange bit." src="https://images.theconversation.com/files/398749/original/file-20210504-13-1g7ruou.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/398749/original/file-20210504-13-1g7ruou.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=366&fit=crop&dpr=1 600w, https://images.theconversation.com/files/398749/original/file-20210504-13-1g7ruou.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=366&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/398749/original/file-20210504-13-1g7ruou.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=366&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/398749/original/file-20210504-13-1g7ruou.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=460&fit=crop&dpr=1 754w, https://images.theconversation.com/files/398749/original/file-20210504-13-1g7ruou.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=460&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/398749/original/file-20210504-13-1g7ruou.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=460&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">The great green wall will run through the Sahel region to the south of the Sahara.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/File:Great_green_wall_map.svg">sevgart / wiki</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>Only <a href="https://www.theguardian.com/environment/2020/sep/07/africa-great-green-wall-just-4-complete-over-halfway-through-schedule">4% of the target area</a> has been covered so far, with big variations from country to country. When it is more complete, this experimental project will hopefully limit the frequency of dust storms and slow the movement of sand onto fertile lands and Unesco sites in northern Sudan. It will also contribute to tackling the extreme heatwaves in semi-arid areas such as the capital Khartoum, where the temperature goes well above 40°C during summer. </p>
<p>However, monitoring the impact of the project, which spans 5,000 miles across Africa, requires “big picture” data. This comes from the latest satellites and remote sensing technologies.</p>
<h2>Sand-tracking satellites</h2>
<p>Satellite imagery can provide valuable information about sand movement. For instance satellites are used to monitor the dust storms that transport sand from the Sahara across the Atlantic Ocean to supply the <a href="https://iopscience.iop.org/article/10.1088/1748-9326/1/1/014005#:%7E:text=Here%2520we%2520show%2520that%2520about,or%25200.2%2525%2520of%2520the%2520Sahara.">Amazon rainforest</a> with essential <a href="https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2015GL063040">fertilising nutrients</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/406158/original/file-20210614-73475-1xk1j1f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Satellite image of Sudan with large dust clouds" src="https://images.theconversation.com/files/406158/original/file-20210614-73475-1xk1j1f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/406158/original/file-20210614-73475-1xk1j1f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=474&fit=crop&dpr=1 600w, https://images.theconversation.com/files/406158/original/file-20210614-73475-1xk1j1f.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=474&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/406158/original/file-20210614-73475-1xk1j1f.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=474&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/406158/original/file-20210614-73475-1xk1j1f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=596&fit=crop&dpr=1 754w, https://images.theconversation.com/files/406158/original/file-20210614-73475-1xk1j1f.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=596&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/406158/original/file-20210614-73475-1xk1j1f.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=596&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Dust storm over Sudan, August 2017.</span>
<span class="attribution"><span class="source">NASA MODIS</span></span>
</figcaption>
</figure>
<p>But what about on a smaller scale? How do you predict if and when sand will submerge a field, a watering hole – or a pyramid?</p>
<p>In my own research I have previously used multiple overlapping images taken from aeroplanes to generate digital elevation models for sand dunes in northern Sudan. That led to my current PhD research which focuses on monitoring the movement of sand dunes using satellite optical and radar <a href="https://www.mdpi.com/2072-4292/12/20/3410">images</a>, airborne laser imagery and other techniques. My research also investigates the influence of factors such as wind speed and direction, presence of vegetation and topography.</p>
<p>Colleagues and I ultimately want to develop our understanding of how sand dunes grow in size and how they migrate across the desert. This will enable us to monitor the effectiveness of interventions such as vegetation barriers, helping to combat desertification and climate change and to ensure people in Sudan are able to grow enough food. And we may even be able to predict when and where those pyramids will be buried – and what we can do to prevent it.</p><img src="https://counter.theconversation.com/content/159596/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Ahmed Mahmoud receives funding from the Ministry of Higher Education and Scientific Research-Sudan/ University of Nottingham and the British Geological Survey University Funding Initiative (BUFI). He is affiliated with the University of Nottingham and the British Geological Survey. </span></em></p>Desertification and climate change are threatening ancient sites in the Sahara.Ahmed Mutasim Abdalla Mahmoud, PhD Researcher, Sand Movement in Sudan, University of NottinghamLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1513762020-12-04T22:01:42Z2020-12-04T22:01:42ZMystery monoliths: why conspiracists are ‘meh’ about the phenomenon — and how you can start a better conspiracy<p>The three recent appearances (and two <a href="https://www.cnet.com/news/another-mysterious-monolith-disappeared-in-romania/">subsequent</a> <a href="https://ksltv.com/449486/dps-crew-discovers-mysterious-monolith-from-air-in-remote-utah-wilderness/">removals</a>) of “<a href="https://www.guardian-series.co.uk/news/national-news/18919395.california-monolith-emerges-utah-romania-works-disappear/">monoliths</a>” in Romania, Utah and California are intriguing examples of what can capture the public’s imagination. </p>
<p>These constructions are metallic-looking structures about three or four metres tall, with a simple geometric design and reflective surface. </p>
<p>They’ll look familiar to fans of Arthur C. Clarke’s Space Odyssey novels, sharing an uncanny resemblance to a monolithic structure pivotal to the story. </p>
<p>Adding to the mystery, the Utah monolith was reportedly in place long before it came to light <a href="https://www.cnet.com/news/mysterious-metal-monolith-discovered-in-remote-utah-desert/">on November 18</a>. While its location wasn’t announced, members of the public <a href="https://edition.cnn.com/style/article/utah-monolith-found-trnd/index.html">found Google Earth images</a> of the object dating back to 2016.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1333207303852613632"}"></div></p>
<p>So far, no credible source has suggested the structures are a product of alien technology or supernatural influence. And unlike with UFO sightings and <a href="https://www.popularmechanics.com/military/research/a24152/area-51-history/">Area 51</a> news, governments have not been accused of a <a href="https://www.theguardian.com/film/2014/aug/14/men-in-black-ufo-sightings-mirage-makers-movie">cover-up</a>.</p>
<p>So even though <a href="https://trends.google.com/trends/explore?q=monolith">Google Trends data</a> shows global search interest in “monolith” has shot up since the structures were found, they’re not yet the subject of widespread conspiracy. And a reflection of past similar phenomena suggests they won’t be.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1333828686584324096"}"></div></p>
<h2>Intriguing artefacts</h2>
<p>The maker (or makers) of the curious objects are likely still around, but they’re not talking. In the meantime, the structures call to mind some major oddities and artefacts from the past, all of which gained considerable fame.</p>
<p>Peru’s <a href="https://www.nationalgeographic.com/history/archaeology/nasca-lines/">Nazca lines</a> are one example. These shallow depressions in rock from around 500 BCE form colossal shapes of animals and plants which, intriguingly, are best observed from the air. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/372787/original/file-20201203-13-1o5xfnf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/372787/original/file-20201203-13-1o5xfnf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=398&fit=crop&dpr=1 600w, https://images.theconversation.com/files/372787/original/file-20201203-13-1o5xfnf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=398&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/372787/original/file-20201203-13-1o5xfnf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=398&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/372787/original/file-20201203-13-1o5xfnf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/372787/original/file-20201203-13-1o5xfnf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/372787/original/file-20201203-13-1o5xfnf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The ancient Nazca lines in Peru cover almost 1,000 square kilometres, and form about about 300 different figures.</span>
<span class="attribution"><span class="source">Flickr</span></span>
</figcaption>
</figure>
<p>The <a href="https://www.smithsonianmag.com/arts-culture/crop-circles-the-art-of-the-hoax-2524283/">crop circle</a> phenomenon may also strike a chord. These complex geometric patterns which apparently form overnight in fields across the world have captured imaginations <a href="https://www.livescience.com/26540-crop-circles.html">for decades</a>. </p>
<p>Both these phenomena have produced exotic accounts claiming to explain them. Some <a href="https://www.history.com/shows/ancient-aliens/season-5/episode-8">have said</a> the Nazca lines were created to communicate with space travellers. Crop circles, <a href="https://www.npr.org/sections/13.7/2011/06/15/137188796/mysterious-crop-circles-alien-messages-or-hoax">others say</a>, are the product of alien labour meant to send us a message.</p>
<p>No one knows why the ancient Peruvians made their lines. Their motivations may be hidden forever. Crop circles, however, are a modern occurrence. </p>
<p>And despite claims they couldn’t possibly be made by humans, humans make them all the time, <a href="https://www.nytimes.com/1991/09/10/world/2-jovial-con-men-demystify-those-crop-circles-in-britain.html">often for</a> the enjoyment of their effect on others. Crop circles also <a href="https://www.nationalgeographic.com/travel/destinations/europe/united-kingdom/pictures-crop-circles-tourism-wiltshire-england/">drive</a> <a href="https://stonehengetours.com/weird-wiltshire-stonehenge-crop-circle-tour.htm">tourism</a> in certain parts of the world.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/372786/original/file-20201203-19-13dwm90.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/372786/original/file-20201203-19-13dwm90.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=428&fit=crop&dpr=1 600w, https://images.theconversation.com/files/372786/original/file-20201203-19-13dwm90.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=428&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/372786/original/file-20201203-19-13dwm90.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=428&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/372786/original/file-20201203-19-13dwm90.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=538&fit=crop&dpr=1 754w, https://images.theconversation.com/files/372786/original/file-20201203-19-13dwm90.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=538&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/372786/original/file-20201203-19-13dwm90.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=538&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Crop circles in fields tend to be heavily geometric and often display concentric circles.</span>
<span class="attribution"><span class="source">Flickr</span></span>
</figcaption>
</figure>
<p>But why are we so easily grabbed by such peculiarities anyway? After all, our lives aren’t impacted by them.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/neverending-stories-why-we-still-love-unsolved-mysteries-141046">Neverending stories – why we still love Unsolved Mysteries</a>
</strong>
</em>
</p>
<hr>
<h2>When things don’t make sense</h2>
<p>There are many possible reasons people fix their attention on potential oddities, and even start <a href="https://us.macmillan.com/books/9781429996761">believing</a> strange things about them.
One is that they short-circuit our sense of how the world works — injecting novelty into an otherwise routine and coherent existence. </p>
<p>As the physicist and Nobel Laureate <a href="https://www.nobelprize.org/prizes/physics/1965/feynman/biographical/">Richard Feynman</a> <a href="https://press.princeton.edu/books/hardcover/9780691153032/the-quotable-feynman">said</a>:</p>
<blockquote>
<p>…the thing that doesn’t fit is the most interesting.</p>
</blockquote>
<p>The tendency to imagine alternatives and to entertain a “what if?” scenario is the same reason we love reading speculative fiction.</p>
<p>If the Nazca lines really were etched to communicate with aliens — and if crop circles really represent alien messages targeted at us — the model of the world in our heads would be flipped. </p>
<p>But of course, as the great science communicator Carl Sagan points out, <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3114207/">paraphrasing</a> prominent polymath <a href="https://mathshistory.st-andrews.ac.uk/Biographies/Laplace/">Pierre-Simon Laplace</a>:</p>
<blockquote>
<p>…extraordinary claims require extraordinary evidence.</p>
</blockquote>
<p>There’s nothing to suggest the above phenomena are evidence of anything extraordinary. </p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/372940/original/file-20201203-17-usqili.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/372940/original/file-20201203-17-usqili.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=612&fit=crop&dpr=1 600w, https://images.theconversation.com/files/372940/original/file-20201203-17-usqili.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=612&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/372940/original/file-20201203-17-usqili.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=612&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/372940/original/file-20201203-17-usqili.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=769&fit=crop&dpr=1 754w, https://images.theconversation.com/files/372940/original/file-20201203-17-usqili.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=769&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/372940/original/file-20201203-17-usqili.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=769&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The Antikythera Mechanism is an out-of-place artefact. These are artefacts of historical, archaeological, or paleontological interest which challenge widely accepted historical chronology.</span>
<span class="attribution"><span class="source">Flickr</span></span>
</figcaption>
</figure>
<p>Another interesting “<a href="http://www.badarchaeology.com/out-of-place-artefacts/">out-of-place</a>” artefact is the ancient <a href="https://www.smithsonianmag.com/history/decoding-antikythera-mechanism-first-computer-180953979/">Antikythera mechanism</a>. This is seemingly an analog computer once used to predict astronomical positions and events.</p>
<p>But perhaps most notorious are the old favourites: Egypt’s <a href="https://www.nationalgeographic.com/history/archaeology/giza-pyramids/">Great Pyramid of Giza</a> (and the widespread conjecture surrounding its construction), <a href="https://www.english-heritage.org.uk/visit/places/stonehenge/history-and-stories/history/">Stonehenge</a> in England, and the enigmatic <a href="https://www.easterisland.travel/easter-island-facts-and-info/moai-statues/">Easter Island</a> statues. All have been connected to aliens, lost wisdom or extinct civilisations.</p>
<h2>In case you need a summer project</h2>
<p>When it comes to creating a spectacle worthy of the public’s attention, there are some key lessons to be learned from past successes in making artefacts, including:</p>
<p><strong>Go big</strong></p>
<p>It pays to do something on a large scale, either by making a big artefact, or having small ones appear over a very large area.</p>
<p><strong>Stay obscure</strong> </p>
<p>The meaning of the artefact should remain unclear, or at least allow room for interpretation. It’s in these situations of uncertainty that the human imagination can run wild. </p>
<p>While the monoliths’ intent is unclear, they could be explained as art. <a href="https://www.nytimes.com/2020/11/27/arts/design/john-mccracken-utah-monolith.html">Reports</a> <a href="https://www.theartnewspaper.com/analysis/destructive-sensationalised-and-maybe-not-even-art-the-short-and-shadowy-legacy-of-the-utah-monolith">have pointed</a> to their similarity with artwork by minimalist sculptor John McCracken.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1331627451001282567"}"></div></p>
<p><strong>Aesthetics matter</strong> </p>
<p>It’s nice if the artefact is aesthetically pleasing or interesting. The geometric precision of pyramids and crop circles speaks to significant care and perhaps mathematical sophistication. The monoliths are comparatively <a href="https://globalnews.ca/news/7493097/utah-monolith-romania/">basic</a>.</p>
<p><strong>Be original</strong> </p>
<p>A display that has never been seen before is far more newsworthy. The monoliths are highly derivative of those appearing in Stanley Kubrick’s <a href="https://www.newyorker.com/magazine/2018/04/23/2001-a-space-odyssey-what-it-means-and-how-it-was-made">2001: A Space Odyssey</a>. </p>
<p><strong>Be difficult to copy</strong></p>
<p>The monoliths could have been knocked up in a workshop. The “wow” factor for artefacts usually comes through an appreciation of their complexity, or seeming impossibility of their manufacture. The scale of the Nazca lines speak to this, as do potential efforts to construct Giza and Stonehenge.</p>
<h2>Humans can do amazing things</h2>
<p>Whatever the true explanations, most phenomena can be attributed to human ingenuity and a willingness to persevere. Simply, we must ask: </p>
<ol>
<li>is it likely the means of construction were accessible to humans?</li>
<li>is it likely it served a meaningful purpose for the maker? </li>
</ol>
<p>In most cases, the former is true. Although the time and resources required must have been momentous, it was clearly not <em>impossible</em> to <a href="https://www.history.com/news/ancient-egypt-pyramid-ramp-discovery">build Giza</a>. We’ll probably have to face the fact humans are just very clever and industrious. </p>
<p>It’s harder to be sure the second point is true, although that doesn’t mean it isn’t. </p>
<p>But every now and then we also like to have fun with artefacts and generate something unique and novel, even if it is for entertainment value alone.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-the-ancient-egyptian-economy-laid-the-groundwork-for-building-the-pyramids-107026">How the Ancient Egyptian economy laid the groundwork for building the pyramids</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/151376/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Peter Ellerton is a fellow of the Rationalist Society of Australia</span></em></p>It’s no surprise the unexplained structures have the internet buzzing. But they haven’t entered the ranks of other great conspiracy material — and history helps explain why they probably won’t.Peter Ellerton, Senior Lecturer in Critical Thinking; Curriculum Director, UQ Critical Thinking Project, The University of QueenslandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1224322019-09-04T12:45:29Z2019-09-04T12:45:29ZTemple graffiti reveals stories from ancient Sudan<figure><img src="https://images.theconversation.com/files/289447/original/file-20190826-8845-1qajh9j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Graffiti bullheads carved on the temple walls.
</span> <span class="attribution"><span class="source">RTI: Suzanne Davis and Janelle Batkin-Hall/IKAP, 2016</span></span></figcaption></figure><p>Today the northern region of Sudan that borders with Egypt is mostly desert. But this part of the Nile’s valley was once home to a powerful African civilisation called <a href="https://www.nationalgeographic.com/archaeology-and-history/magazine/2016/11-12/ancient-egypt-nubian-kingdom-pyramids-sudan/">Kush</a>. It traded gold and the products of inner Africa to Egypt and the Mediterranean world beyond. Kush was a major power in this region for over 2000 years, reaching its largest extent when it conquered Egypt and ruled as its 25th Dynasty from about 725-653 BCE. </p>
<p>In the years 300 BCE to 300 CE, Kush was ruled from the capital of <a href="https://whc.unesco.org/en/list/1336/">Meroe</a>. The city, which is today a UNESCO World Heritage Site, was located along the Nile about 100 miles north of modern-day Khartoum, the capital of Sudan. Other regions of Kush remained important, however. These included the older capital region of Napata, which centred on the “holy mountain” of Jebel Barkal and included the nearby pyramid cemetery of El-Kurru.</p>
<p>There were a number of temples and other sacred sites in Kush. And, as our ongoing <a href="https://ikap.us/">research in El-Kurru</a> <a href="https://www.tandfonline.com/eprint/xuVf7XA75mfBRKFTb7xK/full">has documented</a>, visitors to these sites had one particular religious ritual that may strike some as strange: they carved graffiti in important and sacred places.</p>
<p>These graffiti can still be seen today at several sacred sites in what was the kingdom of Kush – on a pyramid and in a temple at El-Kurru, at a seasonal pilgrimage centre called <a href="http://musawwaratgraffiti.mpiwg-berlin.mpg.de/">Musawwarat es-Sufra</a>, and in the <a href="https://www.britannica.com/place/Philae-island-Egypt">Temple of Isis at Philae</a>, at the border with Egypt.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/289449/original/file-20190826-8868-11stkuu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/289449/original/file-20190826-8868-11stkuu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=472&fit=crop&dpr=1 600w, https://images.theconversation.com/files/289449/original/file-20190826-8868-11stkuu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=472&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/289449/original/file-20190826-8868-11stkuu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=472&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/289449/original/file-20190826-8868-11stkuu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=593&fit=crop&dpr=1 754w, https://images.theconversation.com/files/289449/original/file-20190826-8868-11stkuu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=593&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/289449/original/file-20190826-8868-11stkuu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=593&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">El Kurru temple. Geoff Emberling/IKAP, 2014.</span>
</figcaption>
</figure>
<p>We’re the curators of an <a href="http://exhibitions.kelsey.lsa.umich.edu/graffiti-el-kurru/">exhibition</a> detailing the recently discovered graffiti from El-Kurru. The exhibition is on view at the <a href="https://lsa.umich.edu/kelsey">Kelsey Museum of Archaeology</a> at the University of Michigan until March 2020. It features photographs, text, and interactive media presentations that unpack the practice and its importance in Kushite society. <a href="https://lsa.umich.edu/content/dam/kelsey-assets/kelsey-publications/pdfs/Graffiti-as-Devotion.pdf">A catalogue</a> written in conjunction with the exhibition presents selected examples of graffiti from the Nile valley and beyond, including the ancient Roman city of Pompeii.</p>
<p>We are all accustomed to understanding ancient cultures almost entirely through the activities of the powerful elite and the art they left behind in their palaces, temples, and tombs. But that creates a distorted a picture of ancient life – as distorted as such a picture would be today. The graffiti featured in this exhibition allow a glimpse into some of the activities of non-elite people and their religious devotion to particular places. It’s a reminder that society is more than the elite and powerful.</p>
<h2>Marking place and time</h2>
<p>The graffiti at El-Kurru were discovered by a Kelsey Museum archaeological excavation, on a pyramid and in an underground temple at the site. El-Kurru was a royal cemetery for the kings of the Napatan dynasty, who ruled Egypt as the 25th dynasty. But the graffiti date to several hundred years after the kings’ rule. By this time the pyramids and funerary temple were partially abandoned, yet people were visiting the site and carving graffiti. </p>
<p>The graffiti include <a href="http://exhibitions.kelsey.lsa.umich.edu/graffiti-el-kurru/pdf/handout.pdf">clear symbols</a> of ancient Kush, like the ram that represented the local form of the god <a href="https://www.ancient.eu/amun/">Amun</a>, and a long-legged archer who symbolised Kushite prowess in archery. There are also intricate textile designs as well as animals – beautiful horses, birds, and giraffes. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/289450/original/file-20190826-8868-1jzzdhm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/289450/original/file-20190826-8868-1jzzdhm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=210&fit=crop&dpr=1 600w, https://images.theconversation.com/files/289450/original/file-20190826-8868-1jzzdhm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=210&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/289450/original/file-20190826-8868-1jzzdhm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=210&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/289450/original/file-20190826-8868-1jzzdhm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=265&fit=crop&dpr=1 754w, https://images.theconversation.com/files/289450/original/file-20190826-8868-1jzzdhm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=265&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/289450/original/file-20190826-8868-1jzzdhm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=265&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Graffiti horses. RTI: Suzanne Davis and Janelle Batkin-Hall / IKAP, 2016.</span>
</figcaption>
</figure>
<p>The most common marks are small round holes gouged in the stone. By analogy with modern practices, these are probably areas where temple visitors scraped the wall of the holy place to collect powdered stone that they would ingest to promote fertility and healing.</p>
<h2>Preserving heritage</h2>
<p>Another part of the exhibition focuses on the work we’re doing to preserve the graffiti. The graffiti are carved into soft sandstone that is slowly being eroded. El-Kurru is a windy, desert site prone to sandstorms; it also receives periodic heavy rainstorms that are strong enough to cause flooding. As the surface of the stone wears away from these climatic conditions, so do the graffiti. </p>
<p>It is always difficult to adequately protect archaeological sites like El-Kurru: preservation activities can be expensive, and there are ongoing risks not only from severe weather but also from modern visitors who often like to carve their names into ancient monuments. But preservation work is even harder in a country like Sudan, which has a fragile economy and is undergoing great <a href="https://theconversation.com/why-al-bashirs-fall-is-only-the-start-of-a-new-sudan-115389">social and political upheaval</a>. </p>
<p>We’ve worked with the local community and taken multiple steps to help preserve the graffiti for the future, including physical conservation of the structures into which they are carved. This kind of work has included things like grouting cracks in the stone’s surface with a lime-based mortar. This keeps water from penetrating the cracks and causing the carved surface to detach. But in the exhibition we focus primarily on digital documentation and preservation of the graffiti. </p>
<p>Our goal for this part of the project was to create a very good record of the graffiti as they are now. We used a method called <a href="http://culturalheritageimaging.org/Technologies/RTI/">reflectance transformation imaging</a>. This is a simple photographic technique in which the camera remains perfectly still, focused on a graffito, while about 50 digital photographs are taken. The photographer positions a bright light so that it shines across the surface from a different angle in each photo. Then, software is used to merge all the photographs. The resulting file allows the user, or viewer, to play light across the image from any angle. </p>
<p>There are two big benefits to this type of documentation. First, it is a form of virtual preservation: if the graffiti are lost or damaged in the future there will still be a good record. Second, the digital files allow people to study and enjoy the graffiti, even if they cannot visit the site. The ability to manipulate the lighting direction also means that the graffito can be studied in a way that is not possible with natural light. </p>
<p>This careful documentation of El-Kurru’s graffiti has enabled us to study and understand them in new ways. It has also made it possible to share them with others, including other scholars, to explore their history and meaning. Although many of the graffiti remain mysterious, our ongoing work provides insight on life beyond the elite in ancient Kush: on their religious beliefs, their mobility, and on the importance of certain cultural symbols – even if we don’t yet know what they all mean.</p><img src="https://counter.theconversation.com/content/122432/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Suzanne Davis is the Associate Curator of Conservation at the University of Michigan's Kelsey Museum of Archaeology, and the Director of Conservation for the International Kurru Archaeological Project (IKAP). This story is related to an exhibition, focused on the archaeological site of El-Kurru, which is being held at the Kelsey Museum. Publicity and news stories about the museum and its archaeological excavations are generally beneficial, since they help a larger audience learn about the work. IKAP has received funding from a variety of sources, including the National Geographic Society, the Qatar-Sudan Archaeological Project, and private donors. Conservation work at El-Kurru has also been supported by the Kelsey Museum. In addition to her work for the Kelsey Museum and IKAP, Suzanne Davis is the Vice President of the American Institute of Conservation and serves on the board of directors for the Foundation for Advancement in Conservation. </span></em></p><p class="fine-print"><em><span>Geoff Emberling is the Director of the El-Kurru archaeological project, based at the University of Michigan. The project an an exhibit related to it are the focus of this article and the publicity is generally beneficial to the reputation of the project. The project receives funding from a variety of sources including private donors, private foundations (including recently the National Geographic Society), and government grants (including recently the Qatar Museums Authority). He is also the President of the International Kurru Archaeological Project, Inc., a not-for-profit based in the United States that works to support archaeological research in northern Sudan.</span></em></p>Visitors to these sites had one particular religious ritual that may strike some as strange: they carved graffiti in important and sacred places.Suzanne Davis, Assoc. Curator of Conservation, Kelsey Museum of Archaeology; Director of Conservation for the International Kurru Archaeological Project, University of MichiganGeoff Emberling, Associate Research Scientist in Archaeology, University of MichiganLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1070262018-11-27T15:54:28Z2018-11-27T15:54:28ZHow the Ancient Egyptian economy laid the groundwork for building the pyramids<figure><img src="https://images.theconversation.com/files/247551/original/file-20181127-76749-1jaib9i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Great_Pyramid_of_Giza_(Khufu%E2%80%99s_pyramid),_Pyramid_of_Khafre,_Pyramid_of_Menkaure_(right_to_left)._Giza,_Cairo,_Egypt,_North_Africa.jpg">Mstyslav Chernov</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>In the shadow of the pyramids of Giza, lie the tombs of the courtiers and officials of the kings buried in the far greater structures. These men and women were the ones responsible for building the pyramids: the architects, military men, priests, and high-ranking state administrators. The latter were the ones who ran the country and were in charge of making sure that its finances were healthy enough to construct these monumental royal tombs that would, they hoped, outlast eternity. </p>
<p>In the Old Kingdom, a period that stretches over roughly 500 years (2686–2181 BC), the economy was primarily agrarian and so heavily reliant on the Nile. The river inundated the fields along its banks and provided fertile silt. It also enabled the transport of commodities across the country. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/247745/original/file-20181128-32214-5zogve.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/247745/original/file-20181128-32214-5zogve.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=429&fit=crop&dpr=1 600w, https://images.theconversation.com/files/247745/original/file-20181128-32214-5zogve.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=429&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/247745/original/file-20181128-32214-5zogve.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=429&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/247745/original/file-20181128-32214-5zogve.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=539&fit=crop&dpr=1 754w, https://images.theconversation.com/files/247745/original/file-20181128-32214-5zogve.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=539&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/247745/original/file-20181128-32214-5zogve.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=539&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The tomb of an Old Kingdom official shows agricultural offerings for the tomb owner.</span>
<span class="attribution"><a class="source" href="https://images.metmuseum.org/CRDImages/eg/original/13.183.3_EGDP015505.jpg">Met Museum</a></span>
</figcaption>
</figure>
<p><a href="https://www.researchgate.net/publication/235412579_Estates_Old_Kingdom">Research</a> suggests that the majority of the cultivated soils were part of large estates that were under the control of the crown, various temples, and wealthy estate owners, who were usually royal officials. </p>
<p>Such estates should not be regarded as entirely separate units but as intertwined. They were often part of the same redistribution network, ultimately responded to the king, and were, to a certain extent, reliant on the central state administration. This system may have also involved both formal and informal networks of redistribution and favours. The society of this period has been likened to a feudal system, such as that found in medieval Europe. </p>
<h2>A complex tax system</h2>
<p>In general, the estates, together with towns, were the basic units of economic and societal organisation. The sources suggest that the crown did not tax individuals, such as farmers, since the administration does not seem to have been able to handle the detail of such a task on a countrywide basis. Instead, it burdened the heads of these estates, who were personally liable to deliver revenues to the coffers of the crown, and to ensure that the domain, which they oversaw, delivered the expected surplus. Failure to do so could result in physical punishment. </p>
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Read more:
<a href="https://theconversation.com/great-pyramid-how-my-research-on-ancient-egyptian-poetry-led-to-an-amazing-discovery-106561">Great Pyramid: how my research on ancient Egyptian poetry led to an amazing discovery</a>
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<p>In order to calculate the revenues and thus how much tax would be paid to the royal administration, the crown conducted periodic censuses. Individuals were not counted but rather taxable goods, such as cattle, sheep and goats. It is also clear that other products were collected, such as fabrics and other types of handiwork. </p>
<p>The taxes that the state levied were amassed in granaries and treasuries and then redistributed back to estates or to building projects of various sorts. This could be the construction of a royal tomb and the upkeep of its mortuary cult. Evidence for how such a royal mortuary cult was run has been found at Abusir, just outside modern Cairo. These texts enlighten historians about the daily doings and dealings of the priests, and how the worship of the deceased king was connected to the royal administration and various other temples estates. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/247253/original/file-20181126-140528-1j1djoi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/247253/original/file-20181126-140528-1j1djoi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/247253/original/file-20181126-140528-1j1djoi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/247253/original/file-20181126-140528-1j1djoi.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/247253/original/file-20181126-140528-1j1djoi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/247253/original/file-20181126-140528-1j1djoi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/247253/original/file-20181126-140528-1j1djoi.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">The Abusir pyramids and necropolis remains.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Abusir#/media/File:Pyramids_of_Nyuserre_Ini_and_Neferirkare.jpg">Chanel Wheeler / wikipedia</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<h2>Smooth operation</h2>
<p>The estate chiefs were wealthy, but they did work for it. They were responsible for ensuring that their estates ran smoothly and that their corvée workforce was fed, dressed, and provided shelter. In the pyramid towns at Giza, they were even fed prime beef, fish and beer. This may have been one of the perks of the corvée workforce, which was summoned from various estates across the country for royal monumental constructions.</p>
<p>From Abydos in Upper Egypt, an inscription belonging to Weni, a judge and military commander, indicates that soldiers were conscripted from the same pool of people as the corvée workers. They would take part in various state-sponsored expeditions to mineral-rich lands bordering ancient Egypt. Raw materials like copper and hard wood (which was needed for the larger construction projects) would be brought back to Egypt. Luxury items were also brought to the Nile Valley, including exotic animals, plants, and people for the amusement of the court. The latter were certainly slaves. </p>
<p>At Wadi al Jarf by the Red Sea coast, which functioned as a port during the Old Kingdom, papyri documents from the reign of Khufu have been found. These texts contain a log of a skipper called Merer, and his activity transporting men and goods in and out of Egypt. The papers also tell us how he and his 40 men participated in the construction work of the pyramid by shipping stone from quarries to the construction site of the Great Pyramid at Giza. </p>
<p>It is hypothesised that these projects refined the administrative apparatus and <a href="http://www2.rz.hu-berlin.de/nilus/net-publications/ibaes7/summary.html#Andrassy">fuelled the Egyptian economy</a>. Merer, as well as the estate officials, were working for the royal construction department that was responsible for all major building work in the country and probably also for erecting the large pyramids at Giza and Sakkara to the South. </p>
<p>The workforce – whether a royal administrator or a manual labourer dragging stone at the construction site – provided services to the crown. In turn, the crown reciprocated the labour by redistributing food and other commodities to the work-leaders, who themselves circulated it further down the social ladder. But it was only the people higher up in the hierarchies that could also be rewarded with a state-sponsored mortuary cult next to the king’s tomb.</p><img src="https://counter.theconversation.com/content/107026/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Andreas Winkler 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>In the shadow of the pyramids of Giza, lie the tombs of the courtiers and officials who built these vast structures.Andreas Winkler, Departmental Lecturer in Egyptology and Coptic, University of OxfordLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1065612018-11-08T13:09:28Z2018-11-08T13:09:28ZGreat Pyramid: how my research on ancient Egyptian poetry led to an amazing discovery<figure><img src="https://images.theconversation.com/files/244366/original/file-20181107-74757-1nzaxpf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/ancient-egyptian-pyramid-against-blue-sky-7867366">Shutterstock</a></span></figcaption></figure><p>What began as an expedition to record the inscriptions of ancient Egyptian quarry workers produced a remarkable discovery about the Great Pyramid at Giza. My colleagues and I in the Anglo-French <a href="https://www.liverpool.ac.uk/archaeology-classics-and-egyptology/blog/2018/hatnub/">joint archaeological mission</a> to the ancient quarry site of Hatnub recently revealed the existence of a well-preserved haulage ramp dating to the time of the Great Pyramid, roughly 4,500 years ago.</p>
<p>We think this could significantly change the theories about how the workers who built the monument were able to transport such large blocks of stone to great heights. It could even provide evidence that pulleys were invented hundreds of years earlier than previously documented.</p>
<p>The rock-cut ramp is flanked by two flights of rock-cut stairs, into which are cut post holes that would originally have held wooden posts, now long perished. The pattern of post holes is well enough preserved that we can begin to reconstruct a pulley system that would have been used to lift large blocks of alabaster out of the open-cast quarry.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/244358/original/file-20181107-74751-cvb5yv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/244358/original/file-20181107-74751-cvb5yv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/244358/original/file-20181107-74751-cvb5yv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/244358/original/file-20181107-74751-cvb5yv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/244358/original/file-20181107-74751-cvb5yv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/244358/original/file-20181107-74751-cvb5yv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/244358/original/file-20181107-74751-cvb5yv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The ancient ramp.</span>
<span class="attribution"><span class="source">Roland Enmarch</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>While some quarrymen would have been stationed above the blocks, hauling them upwards directly, others would have stood below the blocks, pulling downwards. Their ropes would have been lashed round the post holes and attached to the alabaster blocks, so that both groups were exerting force to pull the blocks up out of the quarry.</p>
<p>This stone haulage system makes efficient use of the limited available space on the ramp, and it is reasonable to speculate that this same pulley technology would also have been used in the construction of the Great Pyramid. While pulley systems are well known from Greek civilisation in the <a href="https://www.cambridge.org/core/journals/journal-of-hellenic-studies/article/lifting-in-early-greek-architecture/83AECC23A4CFF572B9B01B204832F222">first millennium BC</a>, the evidence from Hatnub pushes their use much further back in time, as it pre-dates the Greek evidence by some 2,000 years.</p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/244360/original/file-20181107-74766-1gsk6l0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/244360/original/file-20181107-74766-1gsk6l0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=902&fit=crop&dpr=1 600w, https://images.theconversation.com/files/244360/original/file-20181107-74766-1gsk6l0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=902&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/244360/original/file-20181107-74766-1gsk6l0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=902&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/244360/original/file-20181107-74766-1gsk6l0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1133&fit=crop&dpr=1 754w, https://images.theconversation.com/files/244360/original/file-20181107-74766-1gsk6l0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1133&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/244360/original/file-20181107-74766-1gsk6l0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1133&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Steep incline.</span>
<span class="attribution"><span class="source">Roland Enmarch</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The Hatnub haulage ramp is also <a href="https://www.jstor.org/stable/27801624?seq=1#page_scan_tab_contents">much steeper</a> than most previous reconstructions of Egyptian haulage ramps. This is significant because one of the long-standing <a href="https://vdocuments.mx/on-pyramid-building-ii.html">objections to the theory</a> that the Great Pyramid was build using a single large ramp was the enormous volume of such a ramp (which would have had a greater volume than the Great Pyramid itself). With a much steeper gradient, the length and volume of such a haulage ramp would be much smaller, suggesting that this old theory needs to be re-evaluated more seriously.</p>
<p>Many <a href="https://www.jstor.org/stable/25148110">other theories</a> have previously been proposed for how the Great Pyramid was constructed. For example, a ramp might have coiled around the sides of the pyramid. There are also many suggestions <a href="http://plaza.ufl.edu/pailos/R_Hussey%20MA%20Thesis%202005.pdf">involving levers</a> and similar mechanisms. (And, of course, there are always those lacking in imagination who cannot accept a human explanation, and instead groundlessly <a href="https://www.express.co.uk/news/weird/940347/Time-travel-speed-of-light-prof-aliens-built-pyramids-UFO/amp">evoke aliens</a> or Atlanteans). The merit of our recent discoveries is that they give us solid archaeological evidence we can use to test previous theories. </p>
<h2>Ancient graffiti</h2>
<p>These discoveries have emerged from the work of the University of Liverpool’s joint expedition with the French Institute for Oriental Archaeology in Cairo to Hatnub, which is some 20km from the Nile in the eastern desert of Middle Egypt. This quarry was the most prestigious ancient source of Egyptian alabaster, the milky white banded translucent stone that was used by the Egyptians to make vessels, statues, and architectural items. </p>
<p>Our original aim was purely to record the <a href="https://www.ees.ac.uk/hatnub">surviving inscriptions left by quarrymen</a> 4,500 to 4,000 years ago. I began my career studying Egyptian poetry, but it turns out quarrymen could on occasion get quite poetic when writing their graffiti in the quarry. And so I now study these texts, written in a cursive version of the Egyptian script known as hieratic.</p>
<p>We have so far identified more than 100 <a href="https://livrepository.liverpool.ac.uk/3003807/1/ICE%20XI%20Gourdon%20and%20Enmarch%20contribution.pdf">previously unrecorded texts</a>, offering a wealth of information about the organisation and logistics of the expeditions that came to the quarry to extract alabaster. They mention royal patronage, the hundreds (and, on occasion, thousands) of expedition personnel, the numbers of blocks mined, and the time taken to ferry them to their ultimate destinations.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/244348/original/file-20181107-74763-q2ko6y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/244348/original/file-20181107-74763-q2ko6y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/244348/original/file-20181107-74763-q2ko6y.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/244348/original/file-20181107-74763-q2ko6y.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/244348/original/file-20181107-74763-q2ko6y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/244348/original/file-20181107-74763-q2ko6y.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/244348/original/file-20181107-74763-q2ko6y.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Stone inscriptions.</span>
<span class="attribution"><span class="source">Roland Enmarch</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Some of the inscriptions take a more long-term point of view, and seek to convince future visitors to the quarry that their predecessors were good people, and deserve to be treated with respect (and offerings) after their death. In the 21st century, we are accustomed to talk of “posting” to “walls”. But at Hatnub we have an actual Bronze Age wall whose texts speak across the years, and create a solidarity among those who came to work in the quarry, generation after generation.</p>
<p>More recently we have expanded our work (and our team) to record the wider archaeological features of the extremely well-preserved Bronze Age industrial landscape around the quarry. We are collecting and analysing the stone tools that litter the site, offering insights into the process of extracting blocks from the bedrock. Through experimental archaeology we are learning just how rapidly alabaster needed to be worked before it dried and hardened after extraction.</p>
<p>We are also studying the ancient road connecting the quarry to the Nile Valley, which is flanked by hundreds of simple dry-stone shelters used by workmen for accommodation and stoneworking. We have simple dry-stone religious cairns and other structures of possible ritual function. The recent clearance of debris from the haulage ramp leading out of the quarry has been part of our study of this wider context. </p>
<p>Our ultimate goal is to study all aspects of stone extraction and transport at Hatnub, integrating the rich textual and archaeological evidence to provide a more holistic understanding of quarrying in ancient Egypt. Few sites offer the range and diversity of evidence that survives at Hatnub. We have many years of work ahead of us; the potential for further exciting discoveries is huge.</p><img src="https://counter.theconversation.com/content/106561/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Dr. Roland Enmarch is a Senior Lecturer in Egyptology at the University of Liverpool. His work at Hatnub has been funded by the University of Liverpool, the British Academy, and the Egypt Exploration Society. He wishes to thank the Egyptian Ministry of Antiquities for their support and permission to undertake this work.
</span></em></p>Ancient quarry workers left messages carved on walls like a 4,500-year-old form of social media.Roland Enmarch, Senior Lecturer in Egyptology, University of LiverpoolLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/867832017-11-02T14:11:19Z2017-11-02T14:11:19ZParticle physicists discover mysterious structure in Great Pyramid – here’s how they did it<figure><img src="https://images.theconversation.com/files/192993/original/file-20171102-26438-sdkbqo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Khufu's pyramid is the largest in the Giza pyramid complex.</span> <span class="attribution"><span class="source">Ricardo Liberato/wikipedia</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>Particle physicists have uncovered a large, hidden void in Khufu’s Pyramid, the largest pyramid in Giza, Egypt – built between 2600 and 2500 BC. The discovery, <a href="http://nature.com/articles/doi:10.1038/nature24647">published in Nature</a>, was made using cosmic-ray based imaging and may help scientists work out how the enigmatic pyramid was actually constructed. </p>
<p>The technology works by tracking <a href="https://theconversation.com/explainer-what-are-fundamental-particles-38339">particles called muons</a>. They are very similar to electrons – having the same charge and a quantum property called spin – but are 207 times heavier. This difference in mass is quite important as it turns out it determines how these particles interact when hitting matter. </p>
<p>Highly energetic electrons emit electromagnetic radiation, such as X-rays, when they hit solid matter – making them lose energy and get stuck in the target material. Due to the muon’s much higher mass, this emission of electromagnetic radiation is suppressed by a factor of 207 squared compared to electrons. As a result, muons are not stopped so quickly by any material, they are highly penetrative.</p>
<p>Muons are commonly produced in <a href="https://www.space.com/32644-cosmic-rays.html">cosmic rays</a>. The Earth’s upper atmosphere is constantly bombarded with charged particles from the sun but also from sources outside of our solar system. It is the latter that provide the more energetic cosmic rays that <a href="http://hyperphysics.phy-astr.gsu.edu/hbase/Particles/muonatm.html">can produce muons</a> and other particles in a chain of reactions.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/192999/original/file-20171102-26438-1m1qm55.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/192999/original/file-20171102-26438-1m1qm55.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=337&fit=crop&dpr=1 600w, https://images.theconversation.com/files/192999/original/file-20171102-26438-1m1qm55.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=337&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/192999/original/file-20171102-26438-1m1qm55.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=337&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/192999/original/file-20171102-26438-1m1qm55.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/192999/original/file-20171102-26438-1m1qm55.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/192999/original/file-20171102-26438-1m1qm55.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The known chambers of the pyramid and the newly discovered void.</span>
<span class="attribution"><span class="source">contact@hip.institute</span></span>
</figcaption>
</figure>
<p>As muons have a relatively long lifetime and are pretty stable, they are the most numerous particles seen from cosmic rays at ground level. And although a lot of energy is lost on the way, muons with very high energies do occur. </p>
<h2>Doing science with muons</h2>
<p>The particles are fairly easy to detect. They produce a thin trail of “ionisation” along the path they take – which means that they knock electrons off atoms, leaving the atoms charged. This is quite handy, allowing scientists using several detectors to follow the path of the muon back to its origin. Also, if there’s a lot of material in the way of the muon, it can lose all of its energy and stop in the material and decay (split into other particles) before being detected.</p>
<p>These properties make muons great candidates for taking images of objects that otherwise are impenetrable or impossible to observe. Just like bones produce a shadow on a photographic film exposed to X-rays, a heavy and dense object with a high atomic number will produce a shadow or a reduction in the number of muons being able to pass through that object.</p>
<p>The first time muons were used in this way was in 1955, when E. P. George measured the overburden of rock over a tunnel by comparing the muon flux outside and inside of the said tunnel. The first known attempt to take a deliberate “muogram” <a href="http://lappweb.in2p3.fr/%7Echefdevi/Work_LAPP/Arche/alvarez_70.pdf">happened in 1970</a> when Luis W. Alvarez looked for extended caverns in the second pyramid of Giza, but found none.</p>
<p>Within the last decade or so, <a href="https://cms.cern/content/muon-tomography">muon tomography</a> has experienced a bit of a fresh boost. In 2007, a Japanese collaboration <a href="http://adsabs.harvard.edu/abs/2007E%26PSL.263..104T">took a muogram of the crater of the volcano Mt Asama</a> to investigate its inside structure. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/ZB-MOGw0RMo?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
</figure>
<p>Muon scans <a href="http://www.world-nuclear-news.org/RS-Muons-suggest-location-of-fuel-in-unit-3-0210174.html">are also being used</a> to investigate the Fukushima reactor remnants. In the UK, the University of Sheffield <a href="https://www.sheffield.ac.uk/news/nr/muon-detector-reduce-carbon-emissions-1.380076">is proposing to use measurements</a> of the muon flux to monitor carbon storage sites. </p>
<h2>Exploring Khufu</h2>
<p>The easiest way to use muons to investigate large objects such as a pyramid is to look for differences in the muon flux coming through it. A solid pyramid would leave a shadow or a reduction in the number of muons in that direction. If there is a large hollow void inside the pyramid the muon flux would be increased in the direction of that void. The bigger the difference between “solid” and “hollow” the easier it becomes. </p>
<p>All you need to do is sit somewhere near the ground, look a bit upwards from the horizon towards the pyramid and count the number of muons coming from every direction. As cosmic muons need to be somewhat energetic to pass through a whole pyramid and as our detector “eyes” are relatively small, we need to sit there and count for quite a while, typically several months in order to count enough muons. In the same way as we have two eyes to get a 3D image of the world in our brains, we want two separate detector “eyes” to get a 3D image of the void inside the pyramid.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/192991/original/file-20171102-26432-1vz8vz1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/192991/original/file-20171102-26432-1vz8vz1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/192991/original/file-20171102-26432-1vz8vz1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/192991/original/file-20171102-26432-1vz8vz1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/192991/original/file-20171102-26432-1vz8vz1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/192991/original/file-20171102-26432-1vz8vz1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/192991/original/file-20171102-26432-1vz8vz1.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">Muon telescope setup in front of Khufus Pyramid.</span>
<span class="attribution"><span class="source">contact@hip.institute</span></span>
</figcaption>
</figure>
<p>The interesting thing about the approach of this team is that they have chosen three different detector technologies to investigate the pyramid. The first one is a bit old fashioned but offers a supreme resolution of the resulting image: <a href="http://www.annalsofgeophysics.eu/index.php/annals/article/view/7384">photographic plates</a> which get blackened by the ionisation. These were left for months inside of one of the known chambers in the pyramid and analysed in Japan after data taking was finished.</p>
<p>For the second method <a href="https://arxiv.org/abs/1106.1238">plastic “scintillators”</a> that produce a light flash when a charged particle passes through them were employed. These kinds of detectors are used in several modern neutrino experiments. </p>
<p>And finally <a href="http://www.sciencedirect.com/science/article/pii/S0168900216308166">chambers</a> filled with gas, where the ionisation caused by the charged particles can be monitored, were used to look directly along the direction of the newly discovered cavern.</p>
<p>The electronic signal of those detectors was directly phoned back to Paris via a 3G data link. Of course a pyramid with three known caverns and a large hollow gallery inside is a bit of a complex object to take a muogram of (it only shows light and dark). So often these pictures need to be compared to a computer simulation of the cosmic muons and the known pyramid, with warts and all. In this case, a careful analysis of the pictures of the three detectors and the computer simulation yielded the discovery of a 30 metre long void, up to now unknown, inside of the Great Pyramid of Giza. What a great success for a new toolkit.</p>
<p>The technique can now help us study the detailed shape of this void. While we don’t know anything about the role of the structure, research projects involving scientists from other backgrounds could build on this study to help us discover more about its function.</p>
<p>It’s great to see how cutting-edge particle physics can help us shed light on the most ancient human culture. Perhaps we are witnessing the beginning of a revolution in science – making it truly interdisciplinary.</p><img src="https://counter.theconversation.com/content/86783/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Harald Fox receives funding from STFC. </span></em></p>Cosmic particles called muons may revolutionise many areas of science.Harald Fox, Senior Lecturer of Particle Physics, Lancaster UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/838982017-09-17T10:43:28Z2017-09-17T10:43:28ZRacism is behind outlandish theories about Africa’s ancient architecture<figure><img src="https://images.theconversation.com/files/185641/original/file-20170912-19562-14y394t.jpg?ixlib=rb-1.1.0&rect=793%2C1491%2C4095%2C2405&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The pyramids of Giza on the outskirts of Cairo, Egypt.</span> <span class="attribution"><span class="source">Mohamed Abd El Ghany/Reuters</span></span></figcaption></figure><p>Some of the most impressive buildings and cities ever made by humans can be found in Africa: the ruined city of <a href="http://whc.unesco.org/en/list/364">Great Zimbabwe</a>, <a href="https://www.sanparks.org/parks/mapungubwe/">Mapungubwe</a> in South Africa, Kenya’s <a href="http://whc.unesco.org/en/tentativelists/5501/">Gedi Ruins</a> and <a href="http://www.ancient.eu/Meroe/">Meroe</a> in Sudan. Perhaps the most awe-inspiring of these are the last remaining of the <a href="http://www.ancient.eu/The_Seven_Wonders/">Seven Wonders of the Ancient World</a>, the <a href="https://www.livescience.com/32616-how-were-the-egyptian-pyramids-built-.html">Great Pyramid of Giza</a>, in Egypt.</p>
<p>This should come as no surprise. Africa has an extensive archaeological record, extending as far back as 3.3 million years ago when the <a href="http://www.nature.com/nature/journal/v521/n7552/full/nature14464.html">first-ever stone tool</a> was made in what is today Kenya. The continent’s cultural complexity and diversity is well established; it is home to the world’s oldest-known <a href="http://science.sciencemag.org/content/334/6053/219">pieces of art</a>. And, of course, it is the birth place of modern humans’ ancient ancestors, <a href="http://www.nature.com/nature/journal/v546/n7657/full/nature22336.html"><em>Homo sapiens</em></a>.</p>
<p>Despite all this evidence, some people still refuse to believe that anyone from Africa (or anywhere in what is today considered the developing world) could possibly have created and constructed the Giza pyramids or other ancient masterpieces. Instead, they credit <a href="http://www.bbc.co.uk/history/ancient/egyptians/pyramidology_01.shtml">ancient astronauts, extraterrestrials or time travellers as the real builders</a>. </p>
<p>Well, you may ask, so what? Who cares if relatively few people don’t believe the ancient Egyptians built the pyramids? What’s the harm? Actually, there <em>is</em> great harm: firstly, these people try to prove their theories by travelling the world and desecrating ancient artefacts. Secondly, they perpetuate and give air to the racist notion that only Europeans – white people – ever were and ever will be capable of such architectural feats. </p>
<h2>A threat to world heritage</h2>
<p><a href="http://www.news.com.au/why-did-two-german-hobbyists-deface-a-cartouche-of-khufu-inside-the-great-pyramid-and-what-does-it-have-to-do-with-atlantis/news-story/7db71b6e1e74976cdbe7736c0e5af4c4">In 2014</a> two German pseudo-scientists set out to “prove” that academics were concealing the Giza pyramids’ “real” origin. To do so, they chiselled off a piece of one of the pyramids – of course, without authorisation, so they could “analyse” it.</p>
<p>And earlier in 2017 scientists from the World Congress on Mummy Studies in South America published a communique on their <a href="https://www.facebook.com/wcoms/posts/804089006431344:0">Facebook page</a> to draw attention to the raiding of Nazca graves for a pseudo-scientific research programme called the <a href="https://www.the-alien-project.com/en/">Alien project</a>. It insists that aliens rather than ancient Peruvians were responsible for the famous geoglyphs called the Nazca Lines, despite <a href="https://www.theatlantic.com/science/archive/2017/08/how-to-fake-an-alien-mummy/535251/">all the evidence</a> to the contrary.</p>
<p>Such incidents exemplify the threats to developing nations’ cultural heritage. Conservation authorities around the world must spend a great deal of money to protect and restore unique pieces of heritage, and to guard them against vandalism. For instance, the most recent overhaul planned for the Giza site – back in 2008 – was estimated at a cost of <a href="http://www.al-monitor.com/pulse/en/originals/2016/03/egypt-pyramid-military-tourism-complaints-project.html">USD$45 million</a>.</p>
<p>These are not wealthy nations, as a rule, and it costs money they often don’t have to repair the damage done by, among others, pseudo-scientists.</p>
<h2>Racism and colonial attitudes</h2>
<p>A series of stone circles in South Africa’s Mpumalanga province provides an excellent example of the other problem with pseudo-archaeologists. Some people genuinely believe that these structures were designed by aliens. They scoff at scientific research that <a href="http://witspress.co.za/catalogue/forgotten-world/">proves</a> the stone circles were made by the Koni people using ropes, sticks and wood. They will not even entertain the notion that ancient African tribes could be responsible.</p>
<p>But the same people have no problem believing that medieval Europeans built the continent’s magnificent cathedrals using only ropes, sticks and wood. They dismiss scientific research that <a href="https://www.livescience.com/32616-how-were-the-egyptian-pyramids-built-.html">overwhelmingly proves</a> ancient Africans’ prowess, but insist the documents which contain evidence of Europeans’ construction processes are beyond reproach.</p>
<p>Why is it <a href="http://www.nationalgeographic.com/travel/travel-interests/arts-and-culture/ancient-sites-built-by-aliens/">so hard</a> for some to acknowledge that ancient non-European civilisations like the Aztecs, people from Easter Island, ancient Egyptians or Bantu-speakers from southern Africa could create intricate structures?</p>
<p>The answer is unfortunately as simple as it seems: it boils down to <a href="https://www.theatlantic.com/science/archive/2017/08/how-to-fake-an-alien-mummy/535251/">profound racism</a> and a feeling of white superiority that emanates from the rotting corpse of colonialism.</p>
<p>Colonial powers saw their “subjects” in Africa, South America and Southeast Asia as exotic, fascinating – but ultimately primitive.</p>
<p>An increasing knowledge and understanding of the archaeological record mostly dispelled these notions. But for some, and until nowadays, it seems unthinkable that ancient non-European societies have been resourceful and creative enough to erect such monuments. So, the thinking went, conventional science must have been missing or hiding something: ancient astronauts, aliens, or the lost civilisation of Atlantis. Even some <a href="https://journals.ub.uni-heidelberg.de/index.php/aegyp/article/view/40164/33823">mainstream scholars</a> have dabbled in this thinking. </p>
<h2>Telling the truth</h2>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/185797/original/file-20170913-20570-upk24i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/185797/original/file-20170913-20570-upk24i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/185797/original/file-20170913-20570-upk24i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/185797/original/file-20170913-20570-upk24i.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/185797/original/file-20170913-20570-upk24i.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/185797/original/file-20170913-20570-upk24i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/185797/original/file-20170913-20570-upk24i.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/185797/original/file-20170913-20570-upk24i.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">The ancient city of Meroe.</span>
<span class="attribution"><span class="source">Mohamed Nureldin Abdallah/Reuters</span></span>
</figcaption>
</figure>
<p>The internet and social media has given these modern conspiracy junkies a perfect platform to share their theories. They try to make others believe that scientists are hiding “the truth” about ancient monuments. Sometimes they even succeed. </p>
<p>There is a risk that they will drown out quality knowledge and science with their colourful, outlandish theories. When such bizarre theories emerge, it can water down people’s understanding and appreciation of Africa’s architectural and cultural heritage. </p>
<p>At the same time, these theories can prevent awareness about Africa’s rich heritage from developing. The heirs of the real builders may never learn about their ancestors’ remarkable achievements.</p>
<p>Scientists have a crucial role to play in turning the tide on such harmful theories. Those of us who are doing ongoing research around the continent’s architectural and fossil record should be sharing our findings in a way that engages ordinary people. </p>
<p>We must show them just how awe-inspiring structures like Great Zimbabwe, Meroe and the Giza Pyramids are – not because they were created by some alien race, but because they are living proof of ancient societies’ ingenuity.</p><img src="https://counter.theconversation.com/content/83898/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Julien Benoit receives funding from The Claude Leon Foundation; PAST and its Scatterlings projects; the National Research Foundation of South Africa; and the DST-NRF Centre of Excellence in Palaeosciences (CoE in Palaeosciences).</span></em></p>The belief that ancient Egyptians needed help from supernatural beings to built the Giza pyramids relies, unavoidably, on racism and colonial attitudes.Julien Benoit, Postdoc in Vertebrate Palaeontology, University of the WitwatersrandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/569542016-03-31T10:59:19Z2016-03-31T10:59:19ZHow robot explorers are making the finds of the future<figure><img src="https://images.theconversation.com/files/116652/original/image-20160329-13691-am4iop.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Adao/Shutterstock</span></span></figcaption></figure><p>Gone are the days when archaeology was just a whole load of sand, dust and bones. These days the real explorers are all about the robotics. </p>
<p>As technology has progressed, archaeological tools have become more sophisticated, including the potential to undertake <a href="https://theconversation.com/from-stonehenge-to-nefertiti-how-high-tech-archaeology-is-transforming-our-view-of-history-56628">scientific investigation</a> with zero disturbances of the surrounding material.</p>
<p>With the use of “non-invasive archeology” amazing discoveries can be made, such as the recent <a href="http://phys.org/news/2016-03-technology.html">ground penetrating survey</a> that appeared to indicate <a href="http://www.bbc.co.uk/news/uk-england-coventry-warwickshire-35892218">Shakespeare’s skull</a> might not be in his tomb. </p>
<p>While these developments are all very useful, <a href="http://news.nationalgeographic.com/2015/04/150403-noninvasive-archaeology-ammaia-roman-lusitania-portugal-video/">non-invasive technologies</a> cannot, and never will, provide perfect resolution of the features within hidden spaces. Also, in many cases, there is still a need to physically extract samples for further scientific study – to perform <a href="http://science.howstuffworks.com/environmental/earth/geology/carbon-14.htm">carbon dating</a> to determine the age of artefacts for example. </p>
<h2>When less is more</h2>
<p>It may well be that as in the case of Shakespeare’s skull, disturbance of a site is not allowed for cultural or religious reasons. But in situations where further investigation is permissible, the usual next step after a “big find” in archaeology is to create a hole large enough for humans to enter – though this often has enormous impact on the integrity of the site.</p>
<p>An alternative approach is to use “minimally invasive” archaeology enabled through <a href="http://robotics.leeds.ac.uk/research/">robotic technology</a> – just like the one we’ve developed in collaboration with Scoutek UK to explore the <a href="http://robotics.leeds.ac.uk/research/#top">Great Pyramid of Giza in Egypt</a>. </p>
<p>Minimally invasive robotic devices can investigate hidden spaces through small holes, changing shape to move safely and efficiently while collecting valuable scientific information – perhaps even flying to avoid all contact with the archaeology. </p>
<p>Our Egypt robot was designed to climb 50 meters at an angle of 40 degrees within a 200mm square hole and carry a range of tools such as a drill, camera and sensor to measure the thickness of stone. The expedition <a href="http://edition.cnn.com/2011/WORLD/africa/05/28/pyramid.markings/">discovered writing</a> which had been hidden for thousands of years. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/116785/original/image-20160330-28443-js0a85.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/116785/original/image-20160330-28443-js0a85.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/116785/original/image-20160330-28443-js0a85.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/116785/original/image-20160330-28443-js0a85.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/116785/original/image-20160330-28443-js0a85.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/116785/original/image-20160330-28443-js0a85.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/116785/original/image-20160330-28443-js0a85.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">Did someone steal Shakespeare’s skull?</span>
<span class="attribution"><span class="source">udra11/Shutterstock</span></span>
</figcaption>
</figure>
<p>The beauty of robotics is that the technologies deployed can match site configuration. So for example if a visual inspection is required at a distance close to the entrance point, then the use of endoscope technology (a small camera and light within a flexible tube) could be used through a hole as small a millimetre in diameter. </p>
<p>At this scale, very close up images can be obtained, but providing enough light to illuminate the space for a large scale inspection is unlikely to be feasible. As the hole size increases, image quality is improved and tools such as grippers and sample collectors can be used. At a size of 12mm’s diameter a full range of tools can be used on the tip that can reach up to three metres away.</p>
<p>Other techniques such as <a href="http://www.sciencedirect.com/science/article/pii/S0169555X12004217">structure-from-motion</a> – which uses maths to align separate images – can construct 3D models from a collection of images to survey the space. </p>
<p>And as the quality of cameras and software increases, the quality of these visual mapping techniques will also increase – and approach the sub-millimetre accuracy currently achieved by laser scanners, which are presently too large for minimally invasive archaeology requiring a hole at least 40mm in diameter. </p>
<h2>More than meets the eye</h2>
<p>If the area to be explored is some distance from the entry point, then a mobile robotic device is required – we are currently developing <a href="http://www.sciencedirect.com/science/article/pii/S2405896315009726">robots that can enter a space</a> through a small hole and then reconfigure to form a useful “fuller sized” robot. And we have already created a robot that can enter through a 40mm diameter hole and then reconfigure from a straight bar to form a conventional robot. This robot can then explore up to 100 metres from the entrance hole. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/116784/original/image-20160330-28451-wqlq4o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/116784/original/image-20160330-28451-wqlq4o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/116784/original/image-20160330-28451-wqlq4o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=369&fit=crop&dpr=1 600w, https://images.theconversation.com/files/116784/original/image-20160330-28451-wqlq4o.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=369&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/116784/original/image-20160330-28451-wqlq4o.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=369&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/116784/original/image-20160330-28451-wqlq4o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=463&fit=crop&dpr=1 754w, https://images.theconversation.com/files/116784/original/image-20160330-28451-wqlq4o.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=463&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/116784/original/image-20160330-28451-wqlq4o.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=463&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 robot explorer took pictures from inside the pyramid, which revealed painted hieroglyphs and lines that may have been made by stonemasons.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/w/index.php?curid=282496">Nina No/Wikepedia</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Then there are the flying robots – otherwise known as drones. Although these are currently not small enough to fit through the smaller holes, we are investigating reconfigurable drones and <a href="http://www.space.com/8398-robot-blimps-soar-worlds.html">“blimps”</a> that can be inserted into confined spaces and then inflated. </p>
<p>There are large challenges to overcome in using drones in these situations, such as battery power – operation time is typically less than 20 minutes – avoiding a crash and communications, all which make them a risky option. </p>
<p>Some of these limitations might be overcome through advanced control systems and the rapid advance of battery technology. And we are currently investigating these issues as part of a grand challenge to use robotic technology to <a href="http://motherboard.vice.com/read/robots-will-make-leeds-the-first-self-repairing-city">“repair cities”</a> – potholes and gas leaks may not sound sexy, but these are the issues which can make a big difference to the everyday lives of residents.</p>
<p>It’s clear that where the future is concerned, be it in the field of archaeology or on the city streets of Leeds, robotics can offer us new ways of doing things – often where humans have previously fallen short.</p>
<p>So while we don’t need to worry that robots are <a href="https://theconversation.com/machines-on-the-march-threaten-almost-half-of-modern-jobs-18485">taking over our jobs</a> just yet, perhaps sometime in the future, they will be able to tell us for sure, whether Shakespeare’s skull is in its rightful resting place.</p><img src="https://counter.theconversation.com/content/56954/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Robert Richardson receives funding from Engineering and Physical Sciences Research Council, UK.</span></em></p>Robots can explore where humans fear to tread.Robert Richardson, Professor of Robotics, University of LeedsLicensed as Creative Commons – attribution, no derivatives.