tag:theconversation.com,2011:/us/topics/south-african-karoo-41788/articlesSouth African Karoo – The Conversation2022-07-31T06:44:32Ztag:theconversation.com,2011:article/1854802022-07-31T06:44:32Z2022-07-31T06:44:32ZFootprints take science a step closer to understanding southern Africa’s dinosaurs<figure><img src="https://images.theconversation.com/files/476406/original/file-20220727-1332-rnl1.jpg?ixlib=rb-1.1.0&rect=308%2C232%2C1298%2C783&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A site in Tsiokane (Lesotho) where diverse tridactyl theropod tracks are preserved.
</span> <span class="attribution"><a class="source" href="https://www.tandfonline.com/doi/full/10.1080/08912963.2020.1810681">Author supplied</a></span></figcaption></figure><p>Dinosaurs have captured people’s imaginations more than any other ancient creatures. These reptiles – some large, some small; some carnivores and others herbivores – rose and dominated the world’s landscapes for more than 135 million years during a period known as the <a href="https://www.britannica.com/science/Mesozoic-Era">Mesozoic</a>.</p>
<p>Today, dinosaur fossils can be found in many parts of the world, contained in rock successions. These are a series of strata or rock units in chronological order. South Africa and Lesotho’s main Karoo Basin, for example, contains plentiful dinosaur fossils in the rock succession that formed <a href="https://www.sciencedirect.com/science/article/pii/S0012825219305586">between 220 million and 183 million years ago</a> during the Late Triassic-Early Jurassic period. These ancient remains include body fossils (bones) and trace fossils, which are <a href="https://theconversation.com/my-job-is-full-of-fossilised-poop-but-theres-nothing-icky-about-ichnology-182906">markings</a> in the ancient sediments in the form of footprints and burrows in the ground. </p>
<p>Body fossils can assist in recreating the ancient life forms, understanding what they looked like, their size, and even how they grew and evolved. The problem is that intact body fossils can be rare in some areas. Bone fragments alone cannot help scientists to piece together the puzzle of ancient life. The traces of animals offer another avenue of study.</p>
<p>In the main Karoo Basin, bone fossils of carnivorous dinosaurs called theropods are incredibly scarce. But their footprints, preserved in the rocks during the Late Triassic and Early Jurassic, are abundant. These fossil footprints are a treasure chest of information. They can reveal what organism made the tracks – different animals have different footprint shapes. They offer clues to the creature’s behaviour – hopping on two legs would leave a different footprint pattern than walking on four. They also provide evidence about the substrate conditions when the creature walked, such as whether it sank into wet sand or was standing firmly on dry gravel.</p>
<p>In a <a href="https://www.frontiersin.org/articles/10.3389/fevo.2022.925313/full">recent study</a>, our team looked at around 200 footprints attributed to theropods across a time span of about 35 million years. We wanted to understand how dinosaurs’ feet changed through time in southern Africa. The time interval we studied is critical in dinosaur history because it captures a mass extinction event and the ancient ecosystems’ subsequent recovery period.</p>
<p>Our findings reveal that over time, our local theropods became larger and had a greater diversity than what the body fossil record could suggest. </p>
<h2>Footprints: a closer inspection</h2>
<p>To begin our study, we first looked for diagnostic clues to tell theropod footprints apart from the tracks of other ancient animals. Theropod footprints typically preserve three, slender toe impressions where the footprint is longer than it is wide. The middle toe has a pronounced forward projection. These footprints also commonly preserve fierce claw mark impressions. </p>
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<img alt="" src="https://images.theconversation.com/files/474643/original/file-20220718-71797-pw0u3c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/474643/original/file-20220718-71797-pw0u3c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=569&fit=crop&dpr=1 600w, https://images.theconversation.com/files/474643/original/file-20220718-71797-pw0u3c.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=569&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/474643/original/file-20220718-71797-pw0u3c.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=569&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/474643/original/file-20220718-71797-pw0u3c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=714&fit=crop&dpr=1 754w, https://images.theconversation.com/files/474643/original/file-20220718-71797-pw0u3c.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=714&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/474643/original/file-20220718-71797-pw0u3c.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=714&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">Natural casts of theropod tracks preserved on a cave ceiling, Tsikoane (Lesotho). Insets of dinosaur tracks from Tsikoane (top) and Roma (bottom).</span>
<span class="attribution"><span class="source">Figure by author/Outlines of Meganosaurus (top) and Dracovenator (bottom) are adapted from Ornitholestes (2018) and Martz (2012), respectively.</span></span>
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<p>We know the shape of their feet and how they moved from reconstructions based on theropod body fossil material. Scientists have also learned about these aspects of dinosaurs by <a href="https://www.sciencedirect.com/science/article/pii/S0031018204006728">making modern footprints</a> using their closest living relatives: birds.</p>
<p>Once we identified the theropod footprints in the field, we quantified their footprint shape by measuring a set of <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/pala.12373">standard parameters</a> agreed on by the global dinosaur trace fossil scientist community. Based on these measurements across time and space, we were able to draw conclusions about theropod foot and body size evolution. This is possible because there is a direct link between foot length, and therefore footprint length, and body size (specifically hip heights and body lengths). </p>
<p>Our study recorded a 40% increase in the maximum and average footprint length in the studied time interval of 35 million years. Furthermore, we observed that larger bodied theropods were present, though rare, in the Late Triassic and that they became <a href="https://theconversation.com/meet-the-giant-dinosaur-that-roamed-southern-africa-200-million-years-ago-86004">even larger</a> and more common in the Early Jurassic, during the recovery period following the mass extinction event. </p>
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Read more:
<a href="https://theconversation.com/meet-the-giant-dinosaur-that-roamed-southern-africa-200-million-years-ago-86004">Meet the giant dinosaur that roamed southern Africa 200 million years ago</a>
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<p>These observations echo trends recorded elsewhere in the world. We also observed that through time, theropod footprints became more prevalent. This may suggest that the carnivore population thrived during the recovery period. This change in abundance might, however, also have been influenced by changes in the ancient environment from meandering rivers with lushly vegetated floodplains to shallower ephemeral streams and lakes under dryland conditions. This newer setting is more conducive to preserving footprints because deposits in the soil are less likely to erode.</p>
<p>Based on our measurements, we identified three distinct types of footprint shapes that may be attributed to the three different theropods that roamed the landscape in the Early Jurassic. This means that southern Africa’s theropod footprint record reflects a greater theropod diversity than the scant carnivorous dinosaur body fossil record, which only preserves fragmentary material of two theropods, <a href="https://core.ac.uk/download/pdf/39674608.pdf">Dracovenator</a> and <a href="https://core.ac.uk/display/39675047;%20https://wiredspace.wits.ac.za/handle/10539/15970">Megapnosaurus</a>. </p>
<h2>More to explore</h2>
<p>Another key finding centred on changes to the form of theropods’ footprints. One is that the forward projection of the middle toes (how much further forward it is than the outer two toes) decreased over time. Another change is that small local theropods had shorter middle toe projections than their <a href="https://yadda.icm.edu.pl/yadda/element/bwmeta1.element.baztech-article-BUS6-0019-0023">contemporaneous North American equivalents</a>.</p>
<p>These observations require more investigation to better understand what these changes mean, especially because the middle toe projection has <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/pala.12449">been linked</a> to an animal’s running ability. </p>
<p>Our research illustrates the importance of the understudied fossil footprint record in studying ancient life and how it complements the more explored body fossil record. Make no bones about it: evolutionary changes among southern African dinosaurs can be tracked by examining their footprints.</p><img src="https://counter.theconversation.com/content/185480/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The research for this study was supported by grants obtained by EB as principal investigator: DST-NRF Centre of Excellence in Palaeosciences (GENUS), NRF Competitive Programme, African Origins Platform. During the research period MA was supported by the DST-NRF Centre of Excellence in Palaeosciences (GENUS) and FK was supported by ERDF/Spanish Ministry of Science and Innovation-State Research Agency. </span></em></p>Fossil footprints are a treasure chest of information.Miengah Abrahams, Lecturer, University of Cape TownLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1863592022-07-20T15:40:25Z2022-07-20T15:40:25ZMystery solved: when mammals’ ancestors became warm-blooded<figure><img src="https://images.theconversation.com/files/472848/original/file-20220706-11561-t1sf0e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Tritylodon, a therapsid, reconstructed as a night dwelling warm blooded animal. Note the steam coming out of its lungs.</span> <span class="attribution"><span class="source">Illustrated by Luzia Soares</span></span></figcaption></figure><p>Mammals and birds produce their own body heat and control their body temperatures. This process is known as endothermy, or warm-bloodedness, and it may be one of the reasons why mammals tend to dominate almost every global ecosystem. Warm-blooded animals are more active during both days and nights than their cold-blooded counterparts and they reproduce faster.</p>
<p>But until now it hasn’t been known exactly when endothermy originated in mammalian ancestry. Our new study, <a href="https://www.nature.com/articles/s41586-022-04963-z">just published in Nature</a>, changes that. A combination of scientists’ intuition, fossils from South Africa’s Karoo region and cutting-edge technology has provided the answer: endothermy developed in mammalian ancestors about 233 million years ago during the <a href="https://www.britannica.com/science/Triassic-Period">Late Triassic period</a>.</p>
<p>The origin of mammalian endothermy has been one of the great unsolved mysteries of palaeontology. Many different approaches have been used to try to pinpoint the answer but they have often given vague or conflicting results. We think our method shows real promise because it has been validated using a very large number of modern species. It suggests that endothermy evolved at a time when many other features of the mammalian body plan were also falling into place.</p>
<p>Warm-bloodedness is the key to what makes mammals what they are today. Endothermy was likely the starting point where mammalness evolved: the acquisition of an insulating fur coat; the evolution of a larger brain, supplied with warmer blood; a faster reproduction rate; and a more active life are all defining mammalian traits that evolved because of warm-bloodedness.</p>
<p>Until now, most scientists had speculated that the transition to endothermy was was a <a href="https://doc.rero.ch/record/200125/files/PAL_E3904.pdf">gradual, slow process</a> over tens of millions of years beginning near the Permo-Triassic boundary, although some suggested it happened closer to the origin of mammals, <a href="https://www.science.org/doi/10.1126/science.1203117">about 200 million years ago</a>.</p>
<p>In contrast, our results suggest that it appeared in mammalian ancestors some 33 million years prior to the origin of mammals. The new date is consistent with <a href="https://theconversation.com/what-fossils-reveal-about-the-hairy-history-of-mammals-ancestors-61449">recent findings</a> that many of the traits usually associated with “mammalness”, such as whiskers and fur, also evolved earlier than previously expected. And according to our results, endothermy evolved very quickly in geological terms, in less than a million years. We suggest that the process may have been triggered by novel mammal-like metabolic pathways and the origin of fur.</p>
<h2>Scientists’ intuition</h2>
<p>Our research began with Dr Araújo and Dr David’s intuition about the inner ear. It is more than the organ of hearing: it also houses the organ of balance, the semicircular canals. </p>
<p>The three semicircular canals of the inner ear are oriented in the three dimensions of space. They’re filled with a fluid that flows in the canals as the head moves and activates receptors to tell the brain the exact three-dimensional position of the head and body. The viscosity, or runniness, of this fluid (called the endolymph) is critical to the balance organ’s ability to efficiently detect head rotation and aid balance.</p>
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<img alt="A skull with prominent front teeth is displayed side-on, the brain shaded in dark pink and a small green spot denoting the inner ear" src="https://images.theconversation.com/files/472847/original/file-20220706-95-fuggny.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/472847/original/file-20220706-95-fuggny.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=376&fit=crop&dpr=1 600w, https://images.theconversation.com/files/472847/original/file-20220706-95-fuggny.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=376&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/472847/original/file-20220706-95-fuggny.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=376&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/472847/original/file-20220706-95-fuggny.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=472&fit=crop&dpr=1 754w, https://images.theconversation.com/files/472847/original/file-20220706-95-fuggny.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=472&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/472847/original/file-20220706-95-fuggny.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=472&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">The brain (pink) and inner ear (green) of a modern mammal, a primate, reconstructed in 3D.</span>
<span class="attribution"><span class="source">Julien Benoit</span></span>
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<p>In the same way as a piece of butter turns from solid to liquid in a warm pan, or honey becomes thicker when it is cold, the viscosity of the endolymph changes with body temperature. That means the endolymph’s viscosity would normally be altered by the evolution of a higher body temperature. But the body has to adapt because changing viscosity would prevent the semicircular canals from working properly. In mammals, the canals adapt to higher body temperature by changing their geometry.</p>
<p>The researchers realised that this change in the semicircular canals’ shape would be easy to trace through geological time using fossils. Pinpointing the species in which the change of geometry occurred would, they reasoned, provide an accurate guide to when endothermy evolved.</p>
<p>They needed fossils to test their hypothesis – and that’s where South Africa’s wealth of fossils from <a href="https://pubs.geoscienceworld.org/gssa/sajg/article/123/2/131/587464/Introduction-to-the-tetrapod-biozonation-of-the">the Karoo region</a> came in.</p>
<h2>Reconstruction and study</h2>
<p>The arid Karoo region preserves a treasure trove of fossils, many of them belonging to mammalian ancestors. These fossils offer an unbroken record of the evolution of life over a period of almost 100 million years. They document the transformation from reptilian-like animals (<a href="https://www.britannica.com/animal/therapsid">therapsids</a>) to mammals in exquisite detail.</p>
<p>Using cutting edge CT-scanning techniques and 3D modelling, we were able to reconstruct the inner ear of dozens of mammalian ancestors from the South African Karoo and elsewhere in the world. From there we could point out exactly which species had an inner ear anatomy consistent with a warmer body temperature, and which ones did not.</p>
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Read more:
<a href="https://theconversation.com/what-fossils-reveal-about-the-hairy-history-of-mammals-ancestors-61449">What fossils reveal about the hairy history of mammals’ ancestors</a>
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<p>One thing we had to take into consideration was the geographical position of the Karoo at the time when these animals lived. It was situated closer to the South Pole than it is now as a result of continental drift. That means the warmer body temperature suggested by the geometry of the inner ear cannot be due to an overall warmer climate. As the South African climate was colder on average, the change in inner ear fluid viscosity can only have been caused by a generally warmer body temperature in mammalian ancestors.</p>
<h2>An exciting time</h2>
<p>This is an exciting time for our field. Until now, to reconstruct the evolution of endothermy, scientists only had access to skeletal features that questionably correlated with warm-bloodedness. Every attempt was a long shot to get any accurate results. The inner ear, as this research shows, changes this. We believe it may be the key to unlocking more knowledge about mammalian ancestors in future.</p><img src="https://counter.theconversation.com/content/186359/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Julien Benoit receives funding from the Palaeontological Scientific Trust (PAST) and its scatterlings projects; the NRF; and the DST-NRF Centre of Excellence in Palaeosciences (GENUS, CoE in Palaeosciences).</span></em></p><p class="fine-print"><em><span>Kenneth D. Angielczyk receives funding from the U.S. National Science Foundation and the Field Museum of Natural History.</span></em></p><p class="fine-print"><em><span>Ricardo Miguel Nóbrega Araújo receives funding from Fundação para a Ciência e a Tecnologia postdoctoral fellowship SFRH/BPD/96205/2013, FCT–AGA KHAN Development Network grant number 333206718, National Geographic Society grant number CP-109R-17, MRI platform member of the national infrastructure France-BioImaging supported by the French National Research Agency (ANR-10-INBS-04, «Investments for the future»), the labex CEMEB (ANR-10-LABX-0004) and NUMEV (ANR-10-LABX-0020). IPFN activities received financial support from through projects UIDB/50010/2020 and UIDP/50010/2020</span></em></p><p class="fine-print"><em><span>Romain David receives funding from the Calleva Foundation. </span></em></p>Warm-bloodedness is the key to what makes mammals what they are today. That’s why working out when it emerged in mammal ancestors matters.Julien Benoit, Senior Researcher in Vertebrate Palaeontology, University of the WitwatersrandKenneth D. Angielczyk, Lecturer, University of ChicagoRicardo Miguel Nóbrega Araújo, Junior Researcher, Universidade de Lisboa Romain David, Postdoctoral Researcher, Natural History MuseumLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1438522020-08-26T15:11:08Z2020-08-26T15:11:08ZTechnology and planning help museums manage outdated exhibitions<figure><img src="https://images.theconversation.com/files/350855/original/file-20200803-18-1wevuy9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">This Jonkeria, an extinct animal from the Karoo that’s much older than the dinosaurs, was among the features of the old exhibition.</span> <span class="attribution"><span class="source">Author supplied</span></span></figcaption></figure><p>Museum exhibitions are all about the “Wow!”, “What?” and “Why?” as they showcase beauty and wonder, spark curiosity, and share some of the important lessons museum scientists have learnt through detailed study of these objects.</p>
<p>But what happens when exhibitions no longer reflect our current understanding of how life on Earth evolved? Science advances all the time and new discoveries are constantly being made. At what point should older exhibitions be dismantled – and what should they be replaced with, given how rapidly knowledge is moving?</p>
<p>These are questions we’ve recently had to mull at the <a href="https://www.iziko.org.za/museums/south-african-museum">Iziko South African Museum</a> in Cape Town. As curators and members of the museum’s Research and Exhibitions team, we had to decide on the future of an iconic exhibition that first opened in 1959. It was the first diorama-style exhibition in South Africa that showcased the fossil discoveries made in the country’s Karoo region. Dioramas are three-dimensional scenes with models and a painted backdrop.</p>
<p>The Boonstra Dioramas were named for <a href="http://www.worldcat.org/identities/lccn-no2009100095/">Dr Lieuwe Dirk Boonstra</a>, a curator and researcher at the South African Museum who dedicated his life to understanding the mysteries of ancient pre-mammalian relatives that looked a lot like modern-day reptiles and dinosaurs, but are actually much older. The dioramas he and his colleagues created represented the best available scientific knowledge about how extinct plants and animals interacted with each other and the Karoo ecosystem around 270 million years ago. </p>
<p>Building on the efforts of science education pioneers like Boonstra, modern scientists now have an even better understanding of Karoo fossils. That has rendered many of the models in the Boonstra Dioramas scientifically inaccurate. But should it remain as a testament to its place in history, to teach us about the process of knowledge generation and the evolution of scientific discovery, or be dismantled to maintain a scientifically accurate and relevant museum?</p>
<p>Museums around the world have been grappling with the issue of diorama removal. Some museums have opted to remove these old dioramas; the Smithsonian National Museum of Natural History in the US has, since 2003, substituted old animal displays with more scientific and modern exhibitions (often digital) emphasising what is currently known of their evolution. </p>
<p>We decided to remove the dioramas. But they’re not lost forever. Thanks to technological advances, we’ve been able to preserve the exhibition digitally. We can do the same with other soon-to-be-retired museum exhibitions – and make space for more up to date exhibitions that reflect the best available science.</p>
<h2>A big moving job</h2>
<p>Before we could turn the dioramas over to technological wizards, we had to decide which objects from the Boonstra Dioramas should be archived for perpetuity and what to do with objects that didn’t make the cut.</p>
<p>A careful de-installation plan was negotiated between museum professionals and building contractors, who oversaw the physical de-installation process. Most of the models were built in place and were too big to fit through the museum doors. As with most dioramas that are only ever viewed from the front, the wall-facing sides of the models didn’t need to be complete. </p>
<p>Many of the wall-facing sides in the Boonstra Diorama models showed a grotesque mesh of wire and plaster that would make it difficult to display them in future historical exhibitions without extensive conservation efforts. Most of these larger models had to be dismantled on site and removed in pieces. Models that were small enough to fit through the door were carefully removed intact. </p>
<p>We were able to salvage and carefully relocate a few scientifically accurate models. </p>
<p>Most of the real fossils (not models or casts) could be carried back into the collections by hand, with one exception. The Bradysaurus, a kind of <a href="https://ucmp.berkeley.edu/anapsids/pareiasauria.html"><em>Pareiasaur</em></a>, was a remarkably complete showcase fossil that had been built into the display. To our surprise, we found this fossil was encased in concrete. Today, plaster of paris, which is much lighter and less brittle than concrete, is used to consolidate the rocks surrounding fossils in the field and to protect the encased fossil during transport to the museum. </p>
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<img alt="" src="https://images.theconversation.com/files/353167/original/file-20200817-20-13awbvo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/353167/original/file-20200817-20-13awbvo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=284&fit=crop&dpr=1 600w, https://images.theconversation.com/files/353167/original/file-20200817-20-13awbvo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=284&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/353167/original/file-20200817-20-13awbvo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=284&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/353167/original/file-20200817-20-13awbvo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=357&fit=crop&dpr=1 754w, https://images.theconversation.com/files/353167/original/file-20200817-20-13awbvo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=357&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/353167/original/file-20200817-20-13awbvo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=357&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">Sibusiso Mthungata, a technical assistant, prepares the Bradysaurus fossil for transport.</span>
<span class="attribution"><span class="source">Author supplied</span></span>
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<p>Thanks to ten strong construction workers and a customised movable dolly, the <em>Bradysaurus</em> specimen was safely removed. It is now in the museum’s behind-the-scenes collection, accessible to researchers for further study. </p>
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Read more:
<a href="https://theconversation.com/a-fossil-hidden-in-plain-sight-in-south-africa-turns-out-to-be-a-new-dinosaur-121597">A fossil hidden in plain sight in South Africa turns out to be a new dinosaur</a>
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<p>Some of the painted backdrops, separated into panels, have found new homes at regional museums. Others will be temporarily housed at Iziko South African Museum until suitable homes can be found.</p>
<p>With the exhibition space cleared, a large blank canvas remains. It will be used for a new permanent exhibition on human evolution, a collaboration between Iziko’s Archaeology Unit and the <a href="https://www.heriuct.co.za/">Human Evolution Research Institute</a> at the University of Cape Town.</p>
<h2>A digital approach</h2>
<p>Several digital technologies have recently emerged to help preserve brick and mortar exhibitions. These include LIDAR, which is 3D laser scanning; and photogrammetry to create high resolution, coloured 3D models that are accurate digital replicas.</p>
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Read more:
<a href="https://theconversation.com/how-we-recreated-a-lost-african-city-with-laser-technology-92852">How we recreated a lost African city with laser technology</a>
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<p>The cost of digital preservation, and particularly LIDAR scanning, is often prohibitive for publicly funded museums. Iziko partnered with the <a href="https://zamaniproject.org/">Zamani Project</a>, a non profit heritage documentation organisation based at the University of Cape Town. Through this collaborative effort the Boonstra Dioramas, including the exquisitely painted backdrops, are now digitally archived.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/350857/original/file-20200803-16-1lmn3sq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/350857/original/file-20200803-16-1lmn3sq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=284&fit=crop&dpr=1 600w, https://images.theconversation.com/files/350857/original/file-20200803-16-1lmn3sq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=284&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/350857/original/file-20200803-16-1lmn3sq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=284&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/350857/original/file-20200803-16-1lmn3sq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=357&fit=crop&dpr=1 754w, https://images.theconversation.com/files/350857/original/file-20200803-16-1lmn3sq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=357&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/350857/original/file-20200803-16-1lmn3sq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=357&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The Zamani Team in action, making fossil replicas digital using a 3D laser scanner.</span>
<span class="attribution"><span class="source">Author supplied</span></span>
</figcaption>
</figure>
<p>A 360-degree panoramic tour is available <a href="https://boonstra360panoramas.zamaniproject.org/">online</a>, allowing visitors an immersive experience of the dioramas. This is a valuable way for museums to connect with a wide range of visitors in a virtual environment during the global COVID-19 pandemic and hopefully beyond. There are also plans to create augmented and virtual reality applications from the digitised exhibition. Additionally, the digital models could be 3D printed to create scaled-down versions of the fossil models. </p>
<p><em>Devonne Kortje, Ralph Schroeder, Laura Rawden, Roshan Bhurtha and Bruce McDonald all contributed to this article.</em></p><img src="https://counter.theconversation.com/content/143852/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Claire Browning receives funding from the South African National Research Foundation (NRF) and through her employment at the Iziko South African Museum. </span></em></p><p class="fine-print"><em><span>Wendy Black receives funding from the National Research Foundation and is a board member of the Human Evolution Research Institute.</span></em></p><p class="fine-print"><em><span>Heinz Ruther and Stephen Wessels do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Museums around the world have been grappling with the issue of diorama removal.Claire Browning, Curator of Karoo Palaeontology, Iziko Museums of South AfricaHeinz Ruther, Professor (em) of Geomatics , Principal Investigator of the Zamani Research Group , UCT, University of Cape TownStephen Wessels, PhD candidate, University of Cape TownWendy Black, Curator of Archaeology, Iziko Museums of South AfricaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1146262019-04-02T13:21:06Z2019-04-02T13:21:06ZNew fossil find may shed light on how sabre toothed predators evolved<figure><img src="https://images.theconversation.com/files/266784/original/file-20190401-177171-4z4wcy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Two gorgonopsian rivals fighting and displaying their large sabre like canines.</span> <span class="attribution"><span class="source">Viktor Radermacher</span></span></figcaption></figure><p>Prehistoric bestiary is full of remarkable creatures and fearsome predators. Sabre toothed cats, with their long, protruding canines, are probably the most recognisable, and have featured a great deal in popular culture like books and <a href="https://www.imdb.com/title/tt0268380">movies</a>.</p>
<p>The African continent had its fair share of these sabre toothed cats. <a href="https://www.maropeng.co.za/news/entry/dinofelis_hominid_hunter_or_misunderstood_feline">Among them</a> were <em>Megantereon</em>, <em>Homotherium</em> and <em>Dinofelis</em>, which shared the ancient landscape with our human ancestors, the early hominims, between one million and five million years ago.</p>
<p>But those cats weren’t the first sabre toothed predators to roam Africa. Some 250 to 260 million years ago, during the Permian period, the world’s most feared sabre toothed predators were <a href="https://core.ac.uk/download/pdf/39674727.pdf">the gorgonopsians</a>.</p>
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Read more:
<a href="https://theconversation.com/why-south-africas-karoo-is-a-palaeontological-wonderland-43045">Why South Africa's Karoo is a palaeontological wonderland</a>
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<p>These sabre toothed carnivores belonged to the family of reptilian-looking mammalian ancestors called the Therapsida. They were found across the continent we know today as Africa, from the south to as far north as <a href="https://books.google.co.za/books?id=dQd2DwAAQBAJ&pg=PA158&lpg=PA158&dq=gorgonopsia+niger&source=bl&ots=k7s2ffihBS&sig=ACfU3U3ktPpgeoB7rIgTJm8Kw_afCyR6Hw&hl=en&sa=X&ved=2ahUKEwiCzpb1567hAhWtQhUIHahrCJ0Q6AEwCXoECAcQAQ#v=onepage&q=gorgonopsia%20niger&f=false">Niger</a>. Gorgonopsians reigned supreme at the top of the food chain for about 10 million years before they were wiped out during the end of the Permian mass extinction event <a href="https://books.google.co.za/books?id=dQd2DwAAQBAJ&pg=PA153&dq=Angielczyk+and+Kammerer+2018+non+mammalian+synapsids&hl=en&sa=X&ved=0ahUKEwjQ_8DPqJjhAhVhQhUIHd3tC3oQ6AEIKjAA#v=onepage&q&f=false">252 million years ago</a>.</p>
<p>Now a team from the Evolutionary Studies Institute at South Africa’s University of the Witwatersrand has discovered the fossil remains of what may be the oldest large-sized gorgonopsian ever found. The extremely well preserved fossil was found in Laingsburg, a town in South Africa’s arid Karoo region. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/266780/original/file-20190401-177187-mamb59.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/266780/original/file-20190401-177187-mamb59.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/266780/original/file-20190401-177187-mamb59.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/266780/original/file-20190401-177187-mamb59.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/266780/original/file-20190401-177187-mamb59.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/266780/original/file-20190401-177187-mamb59.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/266780/original/file-20190401-177187-mamb59.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 snout of the fossil skull found in Laingsburg. The large meat shearing teeth are quite conspicuous.</span>
<span class="attribution"><span class="source">Julien Benoit</span></span>
</figcaption>
</figure>
<p>Gorgonopsians have previously been discovered in similar rock layers from the same area, but these were poorly-preserved specimens of <a href="https://onlinelibrary.wiley.com/doi/abs/10.1002/spp2.1012">small, dog-sized animals</a>. The skull we found is complete, undeformed and lion-sized. This is an important discovery from an evolutionary point of view, because it would show that gorgonopsians started out big. That contradicts what’s known in science as <a href="http://palaeo.gly.bris.ac.uk/benton/reprints/2002Copesrule.html">Cope’s rule</a>, which states that species tend to start small and grow bigger as they evolve.</p>
<h2>Why sabre teeth?</h2>
<p>This discovery, as with any others that involve sabre toothed animals, is also important because it could shed light on how the predators actually used their terrifying teeth.</p>
<p>Some scientists <a href="https://royalsocietypublishing.org/doi/abs/10.1098/rstb.1969.0036">believe</a> it was a lethal stabbing weapon used to pierce prey’s carotid arteries. Some gorgonopsian species had canines longer than the <a href="https://www.cambridge.org/core/journals/the-paleontological-society-papers/article/evolutionary-patterns-in-the-history-of-permotriassic-and-cenozoic-synapsid-predators/F9D50535EFCA6892D73A1F02E8241536">tooth of a tyrannosaur</a>. Others – <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0161457">myself included</a> – argue that a long canine is also represented in herbivores, such as the <a href="https://en.wikipedia.org/wiki/Siberian_musk_deer#/media/File:Moschus_moschiferus_in_Plzen_zoo_(12.02.2011).jpg">musk deer</a> or the <a href="https://en.wikipedia.org/wiki/Muntjac#/media/File:Barking_Deer_-_Kolkata_2011-05-03_2409.JPG">muntjac</a>, which use it for display to attract mates. Gorgonopsians could have had sabre teeth for the same reason. And, of course, the two hypotheses may not be mutually exclusive.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/you-can-thank-our-pre-mammalian-ancestors-for-your-sexy-teeth-65663">You can thank our pre-mammalian ancestors for your sexy teeth</a>
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<p>The only way to answer this question definitively is to find more well preserved fossils such as the recently discovered Laingsburg specimen. With more fossils, we might be able to find out whether both male and female gorgonopsians had sabre-like canines. </p>
<p>If only males did, this could mean the teeth were only important for parading themselves to females, or fighting with other males – rather than for hunting.</p>
<h2>More fossils needed</h2>
<p>The newly discovered large gorgonopsian will now have to be studied carefully to ascertain exactly what we’ve found and what its significance may be. It is currently being cleaned and prepared by technicians at the Evolutionary Studies Institute to remove the rock matrix from the bones. This process can take several months. Then, the discovery will have to be published in a peer-reviewed journal, accompanied by a full description and, possibly, a new species name.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/267035/original/file-20190402-177187-wayjkq.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/267035/original/file-20190402-177187-wayjkq.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/267035/original/file-20190402-177187-wayjkq.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/267035/original/file-20190402-177187-wayjkq.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/267035/original/file-20190402-177187-wayjkq.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/267035/original/file-20190402-177187-wayjkq.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/267035/original/file-20190402-177187-wayjkq.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/267035/original/file-20190402-177187-wayjkq.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">Charlton Dube (ESI, Wits University) uses an airscribe to clean the specimen.</span>
<span class="attribution"><span class="source">Marco Romano</span></span>
</figcaption>
</figure>
<p>Then – with <a href="https://experiment.com/projects/palaeontological-field-exploration-in-the-south-african-karoo/">enough funding</a> – we plan to head back into the field. It’s very possible that there are more beautifully preserved fossils to be found in the Laingsburg area.</p>
<p>With enough fossils, we may get a clearer picture of the ancient Permian environment and be able to solve the mystery of the origin, evolution and death of the “king of the Permian jungle”.</p><img src="https://counter.theconversation.com/content/114626/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Julien Benoit receives funding from the DST-NRF Centre of Excellence in Palaeosciences and the Palaeontological Scientific Trust.</span></em></p>The discovery of a fossilised large predator is a rare event that offers insight into these beasts from the past.Julien Benoit, Postdoc in Vertebrate Palaeontology, University of the WitwatersrandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1021332018-09-11T14:58:12Z2018-09-11T14:58:12ZWhat would it mean to decolonise palaeontology? Here are some ideas<figure><img src="https://images.theconversation.com/files/233835/original/file-20180828-76003-p0zcuu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The fossil of a Mesosaurus tenuidens, which provided important clues about tectonic shifts.</span> <span class="attribution"><span class="source">Courtesy of Philippe Loubry - CNRS/MNHN</span></span></figcaption></figure><p>The call by students to “<a href="https://www.youtube.com/watch?v=C9SiRNibD14">decolonise science</a>” still rings in many South African academics’ ears. But discussions about what t might entail, or even if it’s necessary, <a href="https://www.nature.com/articles/d41586-018-01696-w">are fraught</a>. </p>
<p>In many cases, that’s not because scientists don’t want to reduce the footprint of Western culture on their field of research. Instead, it’s because science is fundamentally meant to be universal. In a perfect world, science would know no cultural or racial discrimination. However, as centuries of <a href="https://christakuljian.com/darwins-hunch/">scientific racism</a> or European exceptionalism remind us, this isn’t a perfect world.</p>
<p>In palaeontology there isn’t a simple answer to questions about what a decolonised version of the field might look like. But certainly part of it must involve acknowledging <a href="https://theconversation.com/its-time-to-celebrate-africas-forgotten-fossil-hunters-77345">Africa’s original fossil hunters</a>, without whom a number of major finds might not have occurred. These were indigenous people who collected fossil shells, teeth and bones that have provided critical clues about our origins. </p>
<p>In most cases, these people seldom received credit for their finds. In the past, <a href="https://www.jstor.org/stable/j.ctt4cgcs9">European researchers</a>, who led many fossil expeditions in Africa, often didn’t bother to mention indigenous people’s contributions, an attitude that would not be tolerated anymore. </p>
<h2>Ancient fossil hunters</h2>
<p>When it comes to the history of African palaeontology, a few famous names come to mind: <a href="https://leakeyfoundation.org/about/the-leakey-family/">Louis and Mary Leakey</a>; <a href="http://www.sahistory.org.za/dated-event/dr-robert-broom-discoverer-mrs-ples-born">Robert Broom</a> and <a href="https://www.britannica.com/biography/Raymond-A-Dart">Raymond Dart</a>.</p>
<p>All of their finds were extremely important. But plenty of fossil finds happened in the preceding centuries. After all humankind <a href="http://humanorigins.si.edu/education/introduction-human-evolution">was born</a> on African soil. And people have roamed the continent for centuries – and they collected fossils along the way. Sometimes these fossils had a practical purpose, like being used as <a href="http://www.sahra.org.za/sahris/heritage-reports/northern-cape-palaeotechnical-report">a pot lid</a>; sometimes they were imbued with <a href="https://www.jstor.org/stable/j.ctt4cgcs9">magical properties</a>; and sometimes they were used <a href="https://www.cambridge.org/core/journals/antiquity/article/folklore-of-fossils-part-i/70106F2791271E5FA24AF39F9F03429D">for decoration</a>.</p>
<p>Many South African sites dating back about 40 000 years ago to the Middle Stone Age indicate that trilobites – small fossilised relatives of crabs and lobsters – were <a href="https://www.sciencedirect.com/science/article/pii/S1464343X17303904">found and transported</a> dozens of kilometres away from their sites of origin by hunter-gatherers. Palaeontologists <a href="https://www.cambridge.org/core/journals/antiquity/article/folklore-of-fossils-part-i/70106F2791271E5FA24AF39F9F03429D">hypothesize</a> the hunter-gatherers either liked the aesthetic of the fossils, or considered them of religious or medicinal importance.</p>
<p>A transported fossil elephant molar at <a href="http://rbins.tumblr.com/post/171443496209/ishango">Congo’s famous Ishango site</a> suggests our ancestors were aware of the presence of unidentifiable animal remains in their surrounding.</p>
<p>And, as early as 300 000 years ago, the earliest <em>Homo sapiens</em> were collecting <a href="http://www.ifrao.com/wp-content/uploads/2018/01/02Erfoud.pdf">fossil sea shells in Morocco</a>. The fossils in question were rather phallic, so it’s been hypothesised that they were involved in some kind of fertility ritual. </p>
<p>Some may say that this was not formal palaeontology. The French palaeontologist <a href="https://www.britannica.com/biography/Georges-Cuvier">Georges Cuvier</a>, who lived from 1769 to 1832, is usually credited as the discipline’s founding father. But it clearly demonstrates that some kind of palaeontological knowledge already existed when the first explorers from overseas arrived on the continent.</p>
<h2>No credit given</h2>
<p>Most people credit the son of a magistrate with <a href="https://beaufortwest.net/explore/beaufort-west/attractions/fossils.html">the first discovery</a> of a fossil in South Africa’s Karoo region, in 1827. But a closer look at the archives reveals that an <a href="https://archive.org/details/ComptesRendusAcademieDesSciences0060?q=mesosaurus+tenuidens">unnamed Griqua person</a> may actually deserve the title. </p>
<p>Some time in the early 1820s this person discovered the fossil of a <em>Mesosaurus</em>, a small reptile that lived some 280 million years ago. </p>
<p>The <em>Mesosaurus</em>‘ fossil presence in both Southern Africa and, later, South America, provided <a href="https://books.google.co.za/books?hl=en&lr=&id=T5mZVQeigpMC&oi=fnd&pg=PR2&dq=mesosaurus+plate+tectonics&ots=E-ToYGL5QJ&sig=ZDuw9upo-itHFVd_qJ85S9chHoM#v=onepage&q&f=false">crucial evidence</a> that the earth’s tectonic plates can shift. </p>
<p>The original collector, whose name was never recorded, is mentioned in passing in a report about the finding by the Frenchman who brought the fossil to Paris. We don’t know if the original collector was paid.</p>
<p>When thinking about how important this fossil became for science, it is sad to think that the original collector, who recognised there was some importance to what others might have dismissed as a useless rock, will never receive the credit he or she deserves for this discovery.</p>
<h2>Recognising the unheralded</h2>
<p>A first step to begin decolonising palaeosciences in Africa would be to give credit where it’s due. The unnamed Griqua collector was just <a href="https://christakuljian.com/darwins-hunch/">one among many</a>.</p>
<p>There is some work being done to ensure that this practice doesn’t continue. For example the two technicians who discovered the famous <em>Australopithecus</em> Little Foot, <a href="https://mg.co.za/article/2017-12-21-00-out-of-the-heart-of-darkness">Nkwane Molefe and Stephen Motsumi</a>, have been amply credited for their effort. </p>
<p>And in 2016 the <a href="https://www.standardmedia.co.ke/article/2000212125/museum-honours-heroes-of-prehistory-research">National Museums of Kenya</a> hailed “Africa’s unsung heroes in prehistory” by honouring technical staff and their important behind the scenes work.</p>
<p>My colleagues and I at the University of the Witwatersrand’s Evolutionary Studies Institute are also working on changing the narrative, such as by hosting a lecture series about South Africa’s first, and largely unacknowledged, <a href="https://www.evensi.com/south-african-fossil-hunters-jorissen-street-2000-johannesburg-gauteng/267895301">fossil hunters</a>.</p>
<p>This sort of initiative could be replicated elsewhere as a way to honour African fossil collectors’ long history and important ongoing contributions to our understanding of the ancient world.</p><img src="https://counter.theconversation.com/content/102133/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Julien Benoit receives funding from the DST-NRF Centre of Excellence in Palaeosciences and the Palaeontological Scientific Trust.</span></em></p>Ancient indigenous people often collected fossil shells, teeth and bones that have provided critical clues about human origins.Julien Benoit, Postdoc in Vertebrate Palaeontology, University of the WitwatersrandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/875412017-12-19T14:56:41Z2017-12-19T14:56:41ZFracking and earthquakes: weighing up the dangers in South Africa<figure><img src="https://images.theconversation.com/files/199681/original/file-20171218-27557-emk4h6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">There are concerns about the negative environmental and social impact of fracking in the Karoo.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/martin_heigan/5065476673/in/photolist-8HBTJH-nCvenD-p6a1s1-4zNnYT-4jVc9T-9tGSZi-6mVVSp-HyWnh-5PPC2k-xz55c-qgywH-4suAfD-HyV3k-vJxX9-oxcJcH-t3hm4-8okwYs-JrDJP-vJxX1-AAeRk-HrjeD-hoZVQW-HiAtg-icnQqN-2CRBYT-9um1fV-6n17BL-hkT6r-4P6f38-f7Yz-5Qct6t-er9WVf-4ovCPw-6n145U-57QcXD-bivixT-47i3ki-F5KFp-7xxw9S-AK3g7-gDPC7B-6VcZfd-8DYKU5-3aKjYM-gJmWLW-ynArZ-pPUWU-AQt58-4FDp4i-pUAm4">Martin Heigan/Flickr</a></span></figcaption></figure><p>The South African government is looking into <a href="https://theconversation.com/why-south-africa-needs-to-pursue-the-potential-of-gas-from-fracking-42271">fracking</a> to reduce the country’s huge reliance on coal for energy. Fracking involves pumping high pressured fluids <a href="https://fracfocus.org/hydraulic-fracturing-how-it-works/hydraulic-fracturing-process">into rock formations</a> to release reserves of oil and gas. </p>
<p>Estimates for gas deposits in the main Karoo region of South Africa range <a href="http://www.sajs.co.za/sites/default/files/publications/pdf/SAJS-113-9-10_DeKock_ResearchArticle.pdf">widely</a>. A few studies have been done for government on the potential for shale gas in the country. These include a report on the technical readiness for a <a href="http://research.assaf.org.za/handle/20.500.11911/14">shale gas industry</a>, a strategic environmental assessment <a href="http://seasgd.csir.co.za/">on shale gas</a> and a <a href="https://juta.co.za/print/catalog/Product/2858">multi-authored academic book</a> on hydraulic fracturing in the Karoo. Government must now integrate this information into policy and develop regulations for the fracking industry.</p>
<p>Environmental groups and landowners <a href="http://www.treasurethekaroo.co.za/fracking-facts">are concerned</a> about the negative environmental and the social impact of fracking. They say that it could have an impact on water quality and quantity, and could also cause habitat fragmentation and loss. They are also worried about possible increased seismicity associated with deep well waste water injection and <a href="http://www.sciencedirect.com/science/article/pii/S0301479716307289">fracking operations</a>. </p>
<p><a href="http://www.wrc.org.za/Knowledge%20Hub%20Documents/Research%20Reports/2149-1-14.pdf">Our research</a> set out to look at the link between earthquakes and fracking. It formed part of the vulnerability mapping for fracking in South Africa. We found that <a href="http://www.wrc.org.za/Knowledge%20Hub%20Documents/Research%20Reports/2149-1-14.pdf">the areas</a> with the highest vulnerability for seismicity linked to fracking were in the parts of Western Cape, Gauteng, North West Province, Mpumalanga, KwaZulu-Natal and one of South Africa’s neighbours, Swaziland. Even though no gas is expected to be found in many of these areas, they would still be prone to the seismic effects of fracking in the Karoo basin, the site of <a href="https://theconversation.com/shale-gas-in-south-africa-game-changer-or-damp-squib-83459">what is assumed to be</a> the country’s biggest gas deposits.</p>
<p>Seismic hazards in South Africa are not high by international norms. But there could be significant damage to infrastructure if seismicity increases.</p>
<h2>Fracking and earthquakes</h2>
<p>During fracking a mixture of water, sand and chemicals – known as fracking fluid – is pumped under high pressure into a well to fracture rock and release hydrocarbons. These hydrocarbons are extracted at the wellhead together with wastewater that contains a mixture of fracking fluid and formation water. The wastewater can be disposed of by injecting it underground through deep wells.</p>
<p>Both extraction and underground injection of fluids have been <a href="https://pubs.er.usgs.gov/publication/70155938">shown to cause earthquakes</a>. But the size of these events are unclear; ranging from relatively small earthquakes such as the magnitude 2.3 in <a href="https://www.politiekemonitor.nl/9353000/1/j4nvgs5kjg27kof_j9vvioaf0kku7zz/viu9lvhwcewb/f=/blg137575.pdf">Blackpool, England</a> to the 5.7 magnitude earthquake in <a href="https://pubs.geoscienceworld.org/geology/article-lookup/41/6/699">Prague, Oklahoma in November 2011</a>.</p>
<p>There have been at least two seismic events of concern with magnitudes equal or larger than 7.0, both in <a href="http://www.sciencedirect.com/science/article/pii/S0264817213000846">Gazli in Uzbekistan</a> where gas is withdrawn. Although they could not be linked directly to fracking, they showed some features associated with fracking-induced earthquakes. </p>
<p>The connection between waste water pumping and seismicity is unquestionable. <a href="https://juta.co.za/print/catalog/Product/2858">Scientists believe</a>, that three factors are responsible for fracking induced or triggered seismic events:</p>
<ul>
<li><p>the presence and orientation of tectonic faults,</p></li>
<li><p>state of stresses in the fault subsurface, and</p></li>
<li><p>the depth and relation between the faults and the fracking process as a whole.</p></li>
</ul>
<h2>Seismic activity in South Africa</h2>
<p>Seismic data of past events in South Africa are incomplete because the <a href="https://pubs.geoscienceworld.org/srl/article-lookup/79/2/203">South African National Seismograph Network</a> primarily monitors areas of mine-related seismicity in the country’s central and northern parts. </p>
<p>The first seismic records were started in 1620, but these contain significant <a href="https://books.google.co.za/books?id=2BhOAQAAIAAJ&q=Seismic+history+of+Southern+Africa+fernandez&dq=Seismic+history+of+Southern+Africa+fernandez&hl=en&sa=X&ved=0ahUKEwiqwaTYmonYAhWFcBoKHRbwDA8Q6AEITDAH">data gaps</a>. Information about active faults that can cause earthquakes is limited; that’s why information from similar tectonic areas like central and eastern US is normally used.</p>
<p>What we do know is that large seismic events – or earthquakes – are rare in South Africa. This is because the country is positioned on the interior of a tectonic plate, a relatively rigid area that’s more stable compared with other <a href="https://link.springer.com/article/10.1007/s10518-017-0152-4">plate boundaries</a>. </p>
<p>The country has experienced several large mining-related earthquakes in the past. One occurred in Stilfontein on <a href="https://pubs.geoscienceworld.org/srl/article-lookup/79/2/203">9 March 2005</a>; another near Orkney on <a href="https://link.springer.com/content/pdf/10.1007%2Fs10950-015-9491-2.pdf">5 August 2014</a>. Both earthquakes, with magnitudes 5.3 and 5.5 respectively, were powerful enough to damage the surrounding infrastructure.</p>
<p>South Africa’s most devastating tectonic-origin earthquake, measuring magnitude 6.3, occurred of the Cape at St Lucia on <a href="https://www.bookdepository.com/History-Geophysics-Southern-Africa-Johan-H-de-Beer/9781920689803">31 December 1932</a>. On September 29 1969 an earthquake measuring 6.3 hit towns in the <a href="https://pubs.geoscienceworld.org/bssa/article-lookup/61/4/851">Western Cape</a>, killing 12 people and causing extensive damage.</p>
<h2>Seismic hazard in South Africa</h2>
<p>The effect of fracking on the local seismic region can be measured by analysing the seismicity before, during, and after the fracking process.</p>
<p>But there is little knowledge on geological information for the Karoo region where fracking has been proposed. Figure one shows the distribution of seismic hazard in South Africa. This means that potentially dangerous faults in the region may go undetected. It’s important to get more geological and tectonic information as well as data about the degree and depths of the proposed fracking process in the region. This could tell us what seismic effect to expect as a result of fracking.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/198974/original/file-20171213-27562-i63jvq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/198974/original/file-20171213-27562-i63jvq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/198974/original/file-20171213-27562-i63jvq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=424&fit=crop&dpr=1 600w, https://images.theconversation.com/files/198974/original/file-20171213-27562-i63jvq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=424&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/198974/original/file-20171213-27562-i63jvq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=424&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/198974/original/file-20171213-27562-i63jvq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=533&fit=crop&dpr=1 754w, https://images.theconversation.com/files/198974/original/file-20171213-27562-i63jvq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=533&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/198974/original/file-20171213-27562-i63jvq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=533&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Map of seismic hazard for South Africa showing the expected PGA with a 10 % probability of being exceeded at least once in a 50 year period.</span>
<span class="attribution"><span class="source">Esterhuyse et al., 2014</span></span>
</figcaption>
</figure>
<p>It is extremely important to monitor local seismic activity before fracking starts to create a baseline for the specific site and surrounding areas. Seismic monitoring before exploration will aid in identifying the location of faults and the stress field nature in areas where it is currently unknown. This, linked with seismic monitoring during and after fracking, can help scientists perform reliable risk assessments to assist with proper regulation.</p>
<hr>
<p><em>This article is the third in a <a href="https://theconversation.com/africa/topics/south-africa-shale-gas-33114">series</a> The Conversation Africa is running on shale gas in South Africa.</em></p><img src="https://counter.theconversation.com/content/87541/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Andrzej Kijko receives funding from Water Research Commission and National Research Foundation.</span></em></p><p class="fine-print"><em><span>Surina Esterhuyse received funding from the Water Research Commission for this research.</span></em></p><p class="fine-print"><em><span>Ansie Smit receives funding from Water Research Commission and National Research Foundation. </span></em></p>It is extremely important to monitor local seismic activity before fracking starts to avoid causing harm.Andrzej Kijko, Director of the Natural Hazard Centre, University of PretoriaSurina Esterhuyse, Lecturer Centre for Environmental Management, University of the Free StateLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/872692017-11-16T18:14:27Z2017-11-16T18:14:27ZGroundwater maps could help South Africa prepare for safer fracking<figure><img src="https://images.theconversation.com/files/195009/original/file-20171116-15428-19j1pnn.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Drilling for water in the Karoo where one major concern from fracking is that groundwater will be affected in the shale gas extraction process.</span> <span class="attribution"><span class="source">Danita Hohne </span></span></figcaption></figure><p>The South African government has made a firm commitment to proceed with unconventional <a href="https://www.gov.za/sites/www.gov.za/files/devplan_2.pdf">gas exploration using fracking</a>. During fracking a mixture of water, sand and chemicals is pumped under high pressure into a deep well to fracture the rock and release “tight” gas that is not easily released by the rock. Speculative estimates of the potential gas resource in the country’s Karoo basin range from <a href="http://www.sajs.co.za/system/tdf/publications/pdf/SAJS-113-9-10_DeKock_ResearchArticle.pdf?file=1&type=node&id=35846&force=">13 to 390 trillion cubic feet of gas</a>, with the lowest estimate being the most realistic. </p>
<p>The extraction of shale gas is an attractive option. It could reduce South Africa’s <a href="http://seasgd.csir.co.za/wp-content/uploads/2016/11/Ch-2-Energy-Planning_13Nov2016_LR.pdf">huge reliance on coal</a> for energy. </p>
<p>But there are also uncertainties around the impact of shale gas extraction. That’s why the Academy of Science investigated South Africa’s <a href="http://research.assaf.org.za/handle/20.500.11911/14">technical readiness</a> for shale gas development. It assessed the status of available information and technologies that can support the development of the shale gas industry. The government also commissioned the strategic environmental assessment for <a href="http://seasgd.csir.co.za/">shale gas development</a>. </p>
<p>One major concern from fracking is that groundwater will be affected in the shale gas extraction process. But a groundwater vulnerability map could help assess these risks. It also has the potential to help government decide which regions can be more safely fracked to limit damage to groundwater resources.</p>
<h2>Groundwater damage</h2>
<p>Groundwater only contributes about <a href="http://www.gwd.org.za/books/groundwater-south-africa">13% of the total water supply of South Africa</a>, but it is an important strategic water source. Two thirds of South Africa’s surface area and more than 300 towns depend largely on groundwater <a href="http://www.gwd.org.za/books/groundwater-south-africa">for drinking water</a>. </p>
<p>Unconventional oil and gas extraction often has an impact on groundwater. Some of these include aquifer damage. An aquifer is an underground layer of water-bearing rock from which groundwater can be extracted using a borehole. During oil and gas extraction, an aquifer can <a href="https://link.springer.com/article/10.1007/s12665-017-6961-6#CR14">experience dewatering</a>, <a href="https://link.springer.com/article/10.1007/s12665-017-6961-6#CR30">deformation,</a> and <a href="https://link.springer.com/article/10.1007/s12665-017-6961-6#CR50">contamination.</a></p>
<p>In some cases, the damage from contamination can be irreversible, such as when aquifer contamination can’t be physically cleaned or rehabilitation is too expensive. Physical cleanup may be impossible, for instance, when certain organic contaminants cannot <a href="https://link.springer.com/article/10.1007/s12665-017-6961-6#CR36">be effectively removed</a>. In the US, hazardous waste cleanup sites present a technical and institutional challenge at more than <a href="https://link.springer.com/article/10.1007/s12665-017-6961-6#CR36">126 000 contaminated locations</a>. Various organic compounds are also used in fracking fluids and therefore represent similar risks to groundwater resources.</p>
<p>Both research reports on shale gas extraction found that it could have an impact on South African groundwater resources. One of the reports found that there were no extra groundwater resources available and that fracking operations would impact existing ones. This report also found that shallow groundwater resources in these water scarce areas may be <a href="http://seasgd.csir.co.za/wp-content/uploads/2016/11/Ch-5_Water_13Nov2016_LR.pdf">contaminated by fracking operations.</a></p>
<p>That’s where the groundwater vulnerability map comes in. It gives the location of sites where the groundwater resource is at risk due to a potentially damaging event linked to fracking, which could cause pollution or destruction of this resource.</p>
<h2>A groundwater vulnerability map</h2>
<p>The <a href="https://link.springer.com/article/10.1007/s12665-017-6961-6">groundwater vulnerability map</a> for unconventional oil and gas extraction shows the areas where groundwater is at risk from unconventional oil and gas extraction. The map is classified from very low to very high vulnerability. Areas with high vulnerability should not be used for exploration and extraction. </p>
<p>But it does not mean that areas with low vulnerability is a free for all and that oil and gas extraction can go ahead freely. The map also shows the location of geological structures where groundwater is more vulnerable to oil and gas extraction, because contamination from for instance spillages can enter the groundwater easier at these locations. Protection zones have been drawn around these vulnerable geological structures and no oil and gas development activities should occur within these zones. </p>
<p>The interactive map has already helped researchers in performing the strategic environmental assessment for shale gas development. It could also be useful assessing water use license applications, oil and gas extraction permit applications and environmental impact assessments. The map presents the relevant groundwater vulnerability information in a central location and in a comprehensible manner.</p>
<p>The interactive vulnerability map will also help regulators with risk assessment. It will ensure consistent interpretations of groundwater vulnerability by different users, if they all use one standard map. And it will enhance the transfer of scientific information to government, consultants and academia.</p>
<p>The map may also be used to guide policy development for unconventional oil and gas extraction for fracking in South Africa. It may assist with the development of effective oil and gas extraction regulations to ensure sustainable development.</p>
<h2>Lessons for South Africa</h2>
<p>Most international vulnerability maps for oil and gas extraction have been produced after fracking operations have already started. They don’t represent baseline maps which show areas that are vulnerable to fracking before the process starts. This is because when fracking was first used to extract oil and gas, information on its possible impact on natural resources, was not yet available. </p>
<p>The value of baseline vulnerability maps was therefore not yet understood. Baseline vulnerability maps could however reduce uncertainty in understanding the risks to humans and wildlife from oil and gas extraction and could be used in adaptive management. It could also present an impartial scientific base for resource management during extraction of oil and gas resources.</p>
<p>Countries that are planning to go ahead with fracking and shale gas extraction have a unique opportunity to address data needs and perform crucial baseline vulnerability mapping before extraction starts.</p>
<p>Such a map should also be linked to an active public access database, much like the <a href="http://www.fractracker.org/map/">Fracktracker database</a>. This is an interactive map that shows information on where extraction takes place by showing well sites, gas pipelines and shale gas deposit localities. And, where available, it shares information on volumes of water and chemicals used and wastewater recovered. Such a map shows information in real time and will lessen data gaps. It will enhance transparency and access to information. This would enable government to better protect natural resources during extraction and could enhance citizen stewardship.</p>
<hr>
<p><em>This article is the second in a <a href="https://theconversation.com/africa/topics/south-africa-shale-gas-33114">series</a> The Conversation Africa is running on shale gas in South Africa.</em></p><img src="https://counter.theconversation.com/content/87269/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Surina Esterhuyse received funding from the Water Research Commission, South Africa, for this research.</span></em></p>A vulnerability map could help assess the risks associated with fracking and groundwater which around 300 towns depend on in South Africa’s Karoo.Surina Esterhuyse, Lecturer Centre for Environmental Management, University of the Free StateLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/850122017-10-16T13:11:53Z2017-10-16T13:11:53ZHow we used the Earth’s magnetic field to date rocks rich in dinosaur fossils<figure><img src="https://images.theconversation.com/files/189742/original/file-20171011-16636-s6gmqy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Barkly Pass, the stratotype for the Elliot Formation. These beautiful rocks hold ancient secrets.</span> <span class="attribution"><span class="source">Lara Sciscio</span></span></figcaption></figure><p>Covering two thirds of South Africa the <a href="http://www.sciencedirect.com/science/article/pii/S1464343X05001184">Karoo Basin</a>, visually, is a beautiful space. When looking more deeply into its rock layers, like leafing through the pages of a book, one can read about a wealth of palaeoevinromental and biological processes. </p>
<p>The Karoo Basin is an invaluable archive of information over its 120 million year depositional history. Rich in fossils, both plants and animals, the Karoo Basin records crisis periods – mass extinction events – in the distant past when many species became extinct.</p>
<p>So far, there have been five main mass extinction events globally. The biggest, the <a href="http://science.nationalgeographic.com/science/prehistoric-world/permian-extinction/">end-Permian</a>, about 252 million years ago, was the Earth’s largest ecological disaster. The Karoo Basin also holds evidence of the third largest mass extinction. This occurred at the end of the Triassic, about 200 million years ago, and heralded the rise of the dinosaurs.</p>
<p>Understanding these climate change events and their impact on biology in the Karoo Basin could influence the way we look at the sixth extinction, which is happening now: the <a href="https://www.smithsonianmag.com/science-nature/what-is-the-anthropocene-and-are-we-in-it-164801414/">Anthropocene</a>. </p>
<p>Scientists need to know when the ancient extinctions happened and for how long. These events are recorded in layers of rock. So we need to know the age of those rocks. There are certain “geological clocks” which help when dating rocks: a mineral called zircon is one. Fossil pollen and spores are others. But when these are scarce, we need another way of measuring the age of rocks. And the Earth’s own magnetic field provides a useful source.</p>
<h2>A different technique</h2>
<p>My colleagues and I were interested in the age of a specific rock unit in the Karoo Basin: the <a href="http://sajg.geoscienceworld.org/content/118/3/311">Elliot Formation</a>. Rocks of the Elliot Formation outcrop in a ring around the Drakensberg Plateau (see figure). The Elliot Formation contains many fossils that shed light on the existence and evolution of dinosaurs in southern Africa. </p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/190136/original/file-20171013-11722-9mss76.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/190136/original/file-20171013-11722-9mss76.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/190136/original/file-20171013-11722-9mss76.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=1113&fit=crop&dpr=1 600w, https://images.theconversation.com/files/190136/original/file-20171013-11722-9mss76.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=1113&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/190136/original/file-20171013-11722-9mss76.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=1113&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/190136/original/file-20171013-11722-9mss76.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1399&fit=crop&dpr=1 754w, https://images.theconversation.com/files/190136/original/file-20171013-11722-9mss76.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1399&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/190136/original/file-20171013-11722-9mss76.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1399&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption"></span>
<span class="attribution"><span class="source">Lara Sciscio</span></span>
</figcaption>
</figure>
<p>This is especially interesting as the Formation is thought to span the end-Triassic mass extinction event. However, the age of the Elliot Formation and where this extinction event occurred within its rock layers was debated. </p>
<p>As there are no radiometric dates from zircons for the Elliot Formation, we used the Earth’s ancient geomagnetic field as a dating tool. This technique has been used globally on <a href="https://www.news.uct.ac.za/article/-2017-09-01-geological-barcodes-a-unique-way-to-date-rocks">similar aged rocks</a>. Applying it here enabled us to narrow down the age of the Elliot Formation to somewhere between about 213 million and 195 million years old. </p>
<p>These dates may help us to answer broader questions relating to the severity of the end-Triassic mass extinction and the post-extinction recovery period in southern Africa. This time line is particularly useful in measuring the diversity of dinosaurs across the bio-crisis and during a critical time in their evolution.</p>
<h2>Magnetic flips</h2>
<p>The Earth generates and sustains a <a href="http://www.physics.org/article-questions.asp?id=64">magnetic field</a> through the motion of the liquid outer core. Some minerals in rocks are able to record the Earth’s magnetic field when they are deposited. Two such minerals, hematite and maghemite, are prevalent in the Elliot Formation. In fact, they lend the Formation a distinct brick-red colour. </p>
<p>Our research <a href="http://www.sciencedirect.com/science/article/pii/S1342937X16302593?via%3Dihub">has found</a> that minerals within the rocks of the Elliot Formation are able to retain primary magnetisations: they have reliably recorded the Earth’s magnetic field at the time of their deposition. That’s important because natural processes can cause “overprinting” – wiping out the original magnetic signature.</p>
<p>This method has been used within the Karoo Basin before on older rocks, but it’s never guaranteed that rocks will retain their primary magnetic signatures. The fact that the Elliot Formation, largely, didn’t fall prey to “overprinting” is what allowed us to record the pattern of the ancient magnetic field.</p>
<h2>Pole reversal offers timing tool</h2>
<p>The Earth’s magnetic field is not constant through time. It “flips” or “reverses” at irregular intervals; on average, every few million years.</p>
<p>When this happens, the magnetic north pole is direct to the geographic south pole and vice versa. Rocks contain alternating layers of north- and south-directed minerals corresponding to every “flip” event. This creates distinct geomagnetic polarity chron(s) – a name to define a specific unit of time during reversals – for any given time period. </p>
<p>By studying the rates and number of these reversals recorded in the Elliot Formation’s rocks, we are able to get a more accurate idea of the rocks’ age. </p>
<p>The next step in pinpointing the Elliot Formation’s relative age was to build its unique magnetic polarity time scale – a log of all the reversal events.</p>
<p>This involved drilling out small samples of rock, using a portable hand-held drill, and orientating them, using a special compass in the field. Thereafter samples were processed in the <a href="https://www.uj.ac.za/faculties/science/geology/Pages/Paleomag-lab.aspx">Paleomag Lab</a> at the University of Johannesburg to recover their unique geomagnetic polarity history. </p>
<p>By doing this, we could build a composite magnetic polarity chronology for the Elliot Formation. We were then able to compare these rocks from South Africa and neighbouring Lesotho to others of a similar time period globally. In so doing, the Elliot Formation records the Earth’s magnetic field as it was about 200 million years ago.</p>
<p>We are not the only ones trying to pin down this important rock unit’s age. We hope that our work will provide a framework on which to place other kinds of information produced by others in this and related fields.</p><img src="https://counter.theconversation.com/content/85012/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Lara Sciscio receives funding from DST-NRF Centre of Excellence in Palaeosciences (CoE in Palaeosciences). </span></em></p>The earth’s own magnetic field offers a useful way to measure the age of rocks - information that can help unpack ancient events and aid our understanding of the present.Lara Sciscio, Postdoctoral Research Fellow in Geological Sciences, University of Cape TownLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/834592017-10-04T14:48:37Z2017-10-04T14:48:37ZShale gas in South Africa: game-changer or damp squib?<figure><img src="https://images.theconversation.com/files/188559/original/file-20171003-12163-ln22ev.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">There are indications shale gas may be present in South Africa's Karoo.</span> <span class="attribution"><span class="source">Reuters/Mike Hutchings</span></span></figcaption></figure><p>Horizontal drilling and hydraulic fracturing, otherwise known as fracking, has in the past few decades made available the gas in previously ‘tight’ shale geologies. This has shaken up the energy sector worldwide by contributing to <a href="https://www.cnbc.com/2017/08/01/oil-survey-sheikhs-versus-shale-to-keep-prices-capped-at-50-in-q3-experts-say.html">relatively low</a> oil prices. Almost all the shale gas development has taken place in the US where production has increased from about 1 to nearly 16 trillion cubic feet (tcf) <a href="https://www.eia.gov/tools/faqs/faq.php?id=907&t=8">over the past 25 years</a>. </p>
<p>There are indications that shale gas may be present in a semi-desert region of South Africa known as the <a href="http://www.places.co.za/html/great_karoo.html">Karoo.</a> The core region alone has an area of 400 000 km². If a viable gas resource were to be developed in the Karoo, what impact would it have on the global shale gas market? And how would it affect the energy economy of South Africa?</p>
<p>A few preliminary studies have been done on the potential for shale gas in the country. These include a report on the technical readiness for a <a href="http://research.assaf.org.za/handle/20.500.11911/14">shale gas industry in South Africa</a>, a strategic environmental assessment on shale gas development commissioned by the Department of Environment <a href="http://seasgd.csir.co.za/">which I co-led</a>, and a <a href="https://juta.co.za/print/catalog/Product/2858">multi-author academic book</a> on hydraulic fracturing in the Karoo. </p>
<p>The research, presented <a href="https://www.assaf.org.za/index.php/news/387-the-shale-gas-industry-in-south-africa-toward-a-science-action-plan">at a recent conference</a>, has led to a clearer picture of both the potential, and the challenges facing shale gas extraction in South Africa. The purpose of the conference, organised by the Academy of Science of South Africa, was to map out a multidisciplinary research plan to fill the critical knowledge gaps.</p>
<h2>How much, how little?</h2>
<p>The studies to date suggest that it’s increasingly unlikely that economically and technically viable gas will be found in the Karoo. First desktop estimates of gas-in-place at depth in the Karoo basin were hundreds of tcf. </p>
<p>More realistic guesses – which is what they remain, in the absence of new exploration and testing – put the upper limit for gas in the Central Karoo at about 20 tcf. This is a tiny resource by global standards. In terms of energy content, 20 tcf of gas is about forty times smaller than the known remaining coal reserves in South Africa. Conventional gas reserves offshore of Mozambique have been estimated at 75 tcf. On the other hand, the continental shelf gas field off <a href="http://www.visitmosselbay.co.za/">Mossel Bay</a> located on South Africa’s garden route, exploited and now nearly depleted, was 1 tcf. </p>
<p>A viable gas find in South Africa, even if quite small, would potentially transform the national energy economy. But making a large investment in infrastructure, regulatory tools, monitoring bodies, and wellfield development for a resource which may not exist is financially, politically and environmentally risky. </p>
<p>Any decisions about how the country should proceed must therefore be based on solid research which is why efforts are under way to adopt a multidisciplinary research programme to fill in the key knowledge gaps. On top of this, good governance is a prerequisite if South Africa is to proceed to shale gas development. </p>
<h2>South Africa’s energy mix</h2>
<p>South Africa’s formal energy economy is <a href="http://www.energy.gov.za/files/coal_frame.html">dominated by coal</a>. But that cannot continue, as the country’s cheap, easily accessible coal reserves are <a href="http://www.sajs.co.za/sites/default/files/publications/pdf/369-2707-5-PB.pdf">nearing an end.</a> Coal mining has also devastated important <a href="http://www.miningweekly.com/article/cer-report-raises-concerns-about-impact-of-mining-in-mpumalanga-2016-06-17/rep_id:3650">agricultural and water-yielding landscapes</a>. Financial institutions are increasingly reluctant to fund new coal-burning power stations because of the impact carbon dioxide emissions are having on the global climate. </p>
<p>As a result, coal-burning power stations are likely, over time, to be replaced by wind and solar energy, or perhaps the more expensive nuclear option. But the degree to which the country’s energy supply can be based on intermittent sources like wind and sunshine depends on the availability of an energy source that can be easily switched on or off to fill the temporary shortfalls between supply and demand – like gas-fired turbines.</p>
<p>South Africa has already decided to increase the fraction of gas in <a href="http://www.gpwonline.co.za/Gazettes/Gazettes/40445_25-11_NationalGovernment.pdf">its energy mix</a>. The only question is where to source it from. Are international imports or domestic sources, like offshore conventional gas or onshore unconventional gas, including shale gas and coal-bed methane better?</p>
<h2>Next steps</h2>
<p>The optimal approach would be to take the first exploratory steps cooperatively, and in the public-domain, rather than in a competitive, secretive and proprietary way. This would allow South Africa to learn about the deep geology of the Karoo and the technologies and hazards of deep drilling, even if no viable gas was found.</p>
<p>A “virtual wellfield”, an imaginary but realistic computer simulation, could be developed on the basis of these findings. This would allow decision-makers and the public to better understand the economic spinoffs and environmental hazards of gas development before any significant actual development occurs. </p>
<p>The continuing low price of oil and the reduced demand for energy caused by the faltering <a href="https://www.dailymaverick.co.za/article/2016-11-03-revealed-the-csirs-outlook-for-south-africas-future-electricity-mix/#.WdM49MYQ-Hs">South African economy</a> buy the country time to do the necessary research and exploration. It can establish the appropriate regulatory environment and institutions before making rushed decisions with large potential consequences.</p>
<p>This is a cautious, evidence-guided agenda which should be acceptable to most people who care both about national development and the quality of the environment.</p>
<hr>
<p><em>This article is the first in a series The Conversation Africa is running on shale gas in South Africa.</em></p><img src="https://counter.theconversation.com/content/83459/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Robert Scholes has received funds from the South African government to co-lead the Strategic Assessment of Shale Gas Development. He is a Trustee of the WWF South Africa. </span></em></p>South Africa’s Karoo region potentially holds shale gas that could transform the energy economy of the country. But given the uncertainties around exploration what’s the next logical step?Robert (Bob) Scholes, Professor Bob Scholes is a Systems Ecologist at the Global Change Institute (GCI), University of the WitwatersrandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/815462017-08-10T09:47:56Z2017-08-10T09:47:56ZNew insights into the survival techniques of a prehistoric beast<figure><img src="https://images.theconversation.com/files/179590/original/file-20170725-28293-1wrlw0h.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Two male _Moschops_ are fighting using their ornamented head as a weapon. </span> <span class="attribution"><span class="source">(Artwork by Alex Bernardini, SimplexPaleo)</span></span></figcaption></figure><p>Imagine a rhinoceros-like beast with a sprawling, lizard-like gait and you will picture quite a good portrait of what <a href="http://digitallibrary.amnh.org/handle/2246/1323"><em>Moschops</em></a> looked like. They are certainly among the most fascinating monsters of the South African prehistoric bestiary. </p>
<p>The <em>Moschops</em> fossil we examined belongs to an animal family called <a href="http://digitallibrary.amnh.org/handle/2246/1323">Dinocephalia</a>. The name translates as “terrible head” or more accurately “terribly large head”, a name that’s richly deserved. They lived in the Middle Permian – around 260-270 million years ago. Their fossils have been found mostly in South Africa and in Russia.</p>
<p>The South African Karoo around Beaufort West is literally stuffed with large remains of dinocephalians’ fossils. Some of them are the remnants of thickened cranial skulls, others pebbles of bones eroded by torrential rains. Before becoming fossils, these bones were part of the impressively thick and horned skull of these massive creatures. </p>
<p>The <em>Moschops</em> fossil we examined was discovered in South Africa in 1911. It would have been safe to assume that nothing new and groundbreaking could be discovered about a fossil found more than a century ago. But that’s not true. The recent development of <a href="http://www.sciencedirect.com/science/article/pii/S0169534714000871">CT and Synchrotron scanning</a> has opened an entire new way of studying fossils, particularly what used to be “soft tissue”, like their brain. The new techniques allowed us to discover previously overlooked features which have simply been out of reach, invisible from the outside.</p>
<p>Our <a href="https://peerj.com/articles/3496/">new study</a> of a complete skull of <em>Moschops</em> has revealed that this thickened and dense braincase was housing a remarkably small and overprotected brain.</p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/181217/original/file-20170807-16718-1gvduet.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/181217/original/file-20170807-16718-1gvduet.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/181217/original/file-20170807-16718-1gvduet.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=650&fit=crop&dpr=1 600w, https://images.theconversation.com/files/181217/original/file-20170807-16718-1gvduet.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=650&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/181217/original/file-20170807-16718-1gvduet.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=650&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/181217/original/file-20170807-16718-1gvduet.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=817&fit=crop&dpr=1 754w, https://images.theconversation.com/files/181217/original/file-20170807-16718-1gvduet.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=817&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/181217/original/file-20170807-16718-1gvduet.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=817&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 skull of <em>Moschops</em> and that of a mammal (platypus) with the same proportions to emphasize the difference in brain size.</span>
<span class="attribution"><span class="source">Author supplied</span></span>
</figcaption>
</figure>
<h2>A very small brain</h2>
<p>With a body weight reaching up to one or two tons and a brain the size of a <a href="https://peerj.com/articles/3496/">chicken egg</a>, <em>Moschops</em>‘s brain was probably one of the smallest among its contemporaneous species. However, small brain size is not an issue when you are the largest animal of your time. Unlike mammals and humans, the ability of the <em>Moschops</em> to survive and reproduce was not a matter of how smart it was, but how strong it was, particularly when it came to fierce head-to-head combat.</p>
<p>Their anatomy shows that male <em>Moschops</em> were ramming into each other like giant, overweight goats <a href="https://theconversation.com/you-can-thank-our-pre-mammalian-ancestors-for-your-sexy-teeth-65663">using their skulls as a weapon</a>.</p>
<p>The very fact that <em>Moschops</em> was practising headbutting testifies to a certain level of social organisation, which is often associated with hierarchical ranking in modern species. So, despite its small brain, the <em>Moschops</em> wasn’t stupid.</p>
<p>Every single behaviour is controlled by the brain, which is a delicate, yet critical soft tissue organ. Incredibly violent behaviour would thus put the brain and nerves into great danger of being injured. </p>
<p><a href="https://peerj.com/articles/3496/">Our discovery</a> shows how, generations after generations, only the animals with the best protected nervous system survived by developing a natural helmet, enabling the dinocephalians to dominate over terrestrial ecosystems for about 10 millions of years as the largest herbivores and the top predators of the middle Permian.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/181218/original/file-20170807-16718-1v8jxl8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/181218/original/file-20170807-16718-1v8jxl8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/181218/original/file-20170807-16718-1v8jxl8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=397&fit=crop&dpr=1 600w, https://images.theconversation.com/files/181218/original/file-20170807-16718-1v8jxl8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=397&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/181218/original/file-20170807-16718-1v8jxl8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=397&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/181218/original/file-20170807-16718-1v8jxl8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=498&fit=crop&dpr=1 754w, https://images.theconversation.com/files/181218/original/file-20170807-16718-1v8jxl8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=498&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/181218/original/file-20170807-16718-1v8jxl8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=498&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 brain of Moschops inside the transparent skull and in its inferred natural position.</span>
<span class="attribution"><span class="source">Author supplied</span></span>
</figcaption>
</figure>
<h2><em>Moschops</em>’s natural head shield</h2>
<p><a href="https://peerj.com/articles/3496/">We discovered</a> that the whole central nervous system was mostly surrounded by an armour of bones, including the brain itself, the inner ear and the nerve responsible for the sensitivity of the face. </p>
<p>This natural helmet could reach up to 15 centimetres of massive bone, the equivalent of a tank armour. Our hypothesis is that the helmet was protecting the brain and sense organs against the brutal shocks of direct head-to-head combat between males to find mates and to defend territory.</p>
<p><em>Moschops</em> is not the only animal to display such an immense thickening of the cranial roof. The <a href="http://www.dinochecker.com/papers/a-taxonomic-review-of-the-Pachycephalosauridae_Sullivan_2006.pdf">pachycephalosaurid dinosaurs</a> (which means “thick-headed lizard”) are also famous for being powerful head butting fighters. This behaviour often led to <a href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0068620">bad bone injuries still visible on fossils today</a>.</p>
<p>In support of the “helmet hypothesis”, we also found that the position of the inner ear inside the braincase of <em>Moschops</em> indicates that the head wasn’t held horizontally as in most animals, but nearly vertically. This places the shielded skull and horns forward, an ideal posture for head butting fights.</p>
<h2>A century long conundrum</h2>
<p>Synchrotron radiation X-ray imaging uses a nearly kilometre long particle accelerator to see through matter – just like a medical scanner <a href="http://www.esrf.eu/">but bigger and way more powerful</a>.</p>
<p>Using these new techniques on the <em>Moschops</em> fossils were able to shed new light on the biology of these emblematic creatures. The techniques have already been used to unravel ancient <a href="https://theconversation.com/technology-has-confirmed-a-theory-about-earths-oldest-venomous-species-72286">envenoming capabilities</a> and the origin of <a href="https://theconversation.com/what-fossils-reveal-about-the-hairy-history-of-mammals-ancestors-61449">hair and whiskers</a> in the remote ancestry of mammals. </p>
<p>There is no doubt that the near future will hold its promises of great breakthrough about long gone prehistoric monsters and our distant ancestors.</p><img src="https://counter.theconversation.com/content/81546/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 Moschops fossil was discovered in South Africa in 1911 and a new study of a complete skull shows how its dense braincase protected the brain and sense organs during head-to-head combat.Julien Benoit, Postdoc in Vertebrate Palaeontology, University of the WitwatersrandLicensed as Creative Commons – attribution, no derivatives.