tag:theconversation.com,2011:/uk/topics/karoo-17716/articlesKaroo – The Conversation2024-03-28T12:17:22Ztag:theconversation.com,2011:article/2247522024-03-28T12:17:22Z2024-03-28T12:17:22ZProtected products: what makes lamb from South Africa’s Karoo and France’s Mont Saint-Michel so special<p>A meal or food shopping experience can be more interesting and enjoyable when you know more about a particular product, like what region it came from and the culture that shaped it. Knowing what makes the food “unique” can improve the tasting experience.</p>
<p>Think about drinking an ice-cold glass of <a href="https://www.vindulge.com/what-is-champagne/">“real” Champagne</a> from France or the satisfaction of serving your dinner guests <a href="https://parmacrown.com/why-prosciutto-di-parma/">“Parma ham”</a> from Italy’s Parma region. </p>
<p>In 1994 the World Trade Organisation put in place an agreement on intellectual property (Trips) that had a <a href="https://www.wto.org/english/docs_e/legal_e/27-trips_04b_e.htm#3">section</a> on Geographical Indications. This increased the protection of certain products, and extended it to more countries. The rights are territorial – the name of a product can only be used if it is sourced from a designated country or region. All members of the WTO are required to make sure this protection happens in their territories. </p>
<p>As a result of the agreement most countries realised they had food products with unique “backstories”. Examples include: Basmati rice (India and Pakistan); Darjeeling tea (India) and Café de Colombia (Colombia).</p>
<p>African countries have also joined the global Geographical Indication family: there’s <a href="https://www.adams.africa/alissa-naran/poivre-de-penja-cameroons-first-eu-geographical-indication/">Poivre de Penja (Penja pepper) from Cameroon</a>, for example. And in 2021 South Africa registered <a href="https://eur-lex.europa.eu/legal-content/EN/TXT/PDF/?uri=CELEX:32021R0865">Rooibos</a>, a locally grown fragrant plant used to make tea. In 2023 it registered <a href="https://www.gov.za/sites/default/files/gcis_document/202310/49556gon3992.pdf">Karoo lamb</a>. This is meat from lambs born and raised in the Karoo, a semi-desert area of the country which gives it a distinctive flavour.</p>
<p>This means that Karoo lamb has its <a href="https://www.news24.com/fin24/economy/amazing-day-for-sa-karoo-lamb-is-now-protected-just-like-champagne-20231027">own Geographical Indication</a> protection with its own unique story.</p>
<p>There are similarities between the backstories of Karoo lamb and Mont Saint-Michel lamb, also known as <a href="http://www.aop-pressales-montsaintmichel.fr/">Agneau de Prés-salés du Mont-Saint-Michel</a> (salt meadow lamb).</p>
<h2>Lamb: two tales</h2>
<p>The story of France’s Agneau de Prés-salés du Mont-Saint-Michel starts in the vast salt marshes that surround the <a href="https://whc.unesco.org/en/list/80/">Mont Saint-Michel abbey, a Unesco World Heritage Site in Normandy, France</a>. The marshes are flooded twice daily by the tides of the English Channel. The sheep that roam these salt meadows feed on a variety of grasses and herbs that impart a distinctive flavour to their meat. </p>
<p>The high saline content of the vegetation, combined with the coastal climate, results in lamb that is tender, succulent, and imbued with the essence of the sea. For centuries the farmers have moved their livestock between different grazing areas seasonally, and during spring and summer the sheep are brought to the salt marshes to graze. In 2013, Mont Saint-Michel lamb was given <a href="https://eur-lex.europa.eu/legal-content/EN/TXT/PDF/?uri=CELEX:52023XC0526(03)">official recognition</a> as a Protected Geographical Indication under European Union law.</p>
<p>This designation acknowledges the unique characteristics of the lamb produced in the bay area and provides legal protection against imitation or misuse of the name. The <a href="https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX%3A52023XC0526%2803%29&qid=1709802332744">status</a> ensures that Mont Saint-Michel lamb can only be produced within the designated geographical area and according to specific production criteria outlined in the official regulations. </p>
<p>South Africa’s Karoo lamb story has echoes of this.</p>
<p>The Karoo covers <a href="https://www.researchgate.net/figure/The-Karoo-region-in-South-Africa-KMOO-2016a_fig1_320066652">almost 50%</a> of the total area of South Africa and is sparsely populated, far away from major urban and distribution centres. This lonely corner of the earth is home to one of South Africa’s living treasures: flocks of sheep, grazing freely among the scattered shrubs. Their meat is spiced on the hoof as the sheep feed on wild vegetation. </p>
<p>Karoo lamb Geographical Indication can now be traced to its own “salt marshes”, in this case the Karoo’s unique shrubs and grasses (“veld”). According to <a href="https://www.greengazette.co.za/notices/agricultural-product-standards-act-119-1990-registration-of-karoo-lamb-karoo-lam-as-a-south-african-geographical-indication-gi_20231027-GGN-49556-03992">the statement</a> giving it this special status: </p>
<blockquote>
<p>It is only Karoo Lamb when it is a lamb which was born and raised on Karoo veld in the defined Karoo region. It has never been in a feedlot, and never grazed on planted pastures. </p>
</blockquote>
<h2>Compliance</h2>
<p>Trading these authentic products outside the region of origin and beyond national borders brings into play a host of problems. These include traceability, labelling and consumers being misled. Protecting the reputation and authenticity of these products needs to be done with great care and precision. </p>
<p>Most high value products with intrinsic value lose their reputation through misappropriation, usurpation and simple fraudulent and counterfeit practices. This is why some form of assurance is critical to protect the value of the product.</p>
<p>Rigorous traceability systems are needed to ensure compliance and to provide the necessary consumer assurance. The regional collective organisation, the <a href="https://www.karoolamb.org/">Karoo Lamb Consortium</a>, tries to ensure the integrity and honesty of all role players – from the farmer to the retailer to the restaurateur.</p>
<p>There are nevertheless opportunities for opportunistic behaviour, dishonesty, shirking and plain food fraud. These include:</p>
<ul>
<li><p>farmers who market feedlot or pasture lamb as Karoo lamb </p></li>
<li><p>abattoirs that source from farms outside the region </p></li>
<li><p>butchers who don’t confirm the origin but sell it as Karoo lamb</p></li>
<li><p>restaurateurs who tell the naive tourist that the lamb on the plate is from the Karoo when it is actually sourced from a feedlot far away from the Karoo.</p></li>
</ul>
<p>Fortunately science can detect the origin of lamb through analysis of the meat and fat. In a 2017 <a href="https://www.sciencedirect.com/science/article/abs/pii/S0308814617307094">paper</a> researchers showed it was possible to authenticate the origin. Their results showed clearly that fat from Karoo lamb had a higher concentration of key terpenes, validating the direct link with the herbaceous plant samples. </p>
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Read more:
<a href="https://theconversation.com/its-true-what-a-sheep-eats-affects-the-taste-of-your-lamb-roast-51877">It's true: what a sheep eats affects the taste of your lamb roast</a>
</strong>
</em>
</p>
<hr>
<p>Overall, the analysis shows considerable differences between the Karoo and non-Karoo samples.</p>
<p>This research was followed by an extensive exercise to develop a database for more regions and sub-regions in the Karoo. Scientists can now easily analyse samples from retail shelves and confirm the authenticity of claims on labels. </p>
<p>These techniques have been <a href="https://oritain.com/">successfully applied</a> to protect the authenticity of Welsh lamb and New Zealand lamb.</p><img src="https://counter.theconversation.com/content/224752/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Johann Kirsten is affiliated with the "Karoo Lamb Consortium".. </span></em></p>Meat from sheep that graze in South Africa’s Karoo and France’s Mont Saint-Michel lamb is deemed special.Johann Kirsten, Director of the Bureau for Economic Research, Stellenbosch UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1586452021-04-19T13:27:12Z2021-04-19T13:27:12ZWhat an unusual fossil reveals about parental care among pre-mammalian ancestors<figure><img src="https://images.theconversation.com/files/395493/original/file-20210416-17-1a8am3l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">This pair of curled-up Diictodon skeletons tell a story of male parental care.</span> <span class="attribution"><span class="source">Authors supplied</span></span></figcaption></figure><p>South Africa’s <a href="https://theconversation.com/why-south-africas-karoo-is-a-palaeontological-wonderland-43045">Karoo region</a> is world famous for its wealth of fossil remains. Many of these are from long extinct land animals that lived between 280 and 200 million years ago. This was a time before the dinosaurs, when all the landmasses were joined into the supercontinent of <a href="https://www.britannica.com/place/Pangea">Pangaea</a>.</p>
<p>Most of the fossil skeletons that have been found in the Karoo belong to <a href="https://www.britannica.com/animal/therapsid">therapsids</a>. These ancient reptilian precursors to mammals are often called “mammal-like reptiles”.</p>
<p>But it is very rare to find therapsid skeletons preserved in underground fossilised burrow casts. These are ancient burrows that were filled by sediments (during a flood for example), and were later deeply buried by time and the elements and turned into rock.</p>
<p>That’s why <a href="https://www.sciencedirect.com/science/article/abs/pii/0031018287900307">a find</a> in the 1980s in the Namakwa district of South Africa’s Northern Cape province, near Fraserburg, was especially significant. Skeletons found in the terminal chamber of spiral-shaped burrow casts demonstrated that they were excavated by a small herbivorous mammal-like reptile called <em>Diictodon</em>. </p>
<p>It wasn’t clear why the animals might have gone underground but it was assumed to be mainly for body temperature regulation. Then, in 2014, some new burrow casts were found at the same site. These contained the scattered skeletons of adult and infant <em>Diictodon</em>. Now, after a few years of careful study, we have been able <a href="https://www.sciencedirect.com/science/article/abs/pii/S0031018221000961?via%3Dihub">to establish</a> that adult males were in the burrows, along with infants of the same species. </p>
<p>This supports the idea that <em>Diictodon</em> went underground to breed and also that adult males may have played a role in feeding and protecting their litter. This is a rare reproductive behaviour for most modern male mammalian species. These new finds indicate that <em>Diictodon</em> was burrowing and giving some parental care to its young. This was long thought to be unique to mammals. Now we have evidence that this behaviour also existed in their remote cousins, the mammal-like reptiles and it deepens the root of “mammalness” – the point in time when mammal-like behaviours first emerged – even further than previously thought.</p>
<h2>Technology sheds light</h2>
<p>Modern animals use burrows for a variety of reasons: avoiding predators, food hoarding, brooding, and avoiding extreme humidity and temperature fluctuations. </p>
<p>In the fossil record it is not always clear what ancient animals were using their burrows for. Luckily, modern technology means that scientists are increasingly able to answer such questions. Our team worked with the <a href="https://www.esrf.fr/">European Synchrotron Radiation Facility</a> in Grenoble, France. </p>
<p>The X-ray beam generated in this synchrotron is 100 billion times brighter than the more common medical X-ray scanners, making it possible to create much sharper images. The technique we used is also much more sensitive to density variation: this is essential when trying to see fossilised bones surrounded by rock that can have very similar density. Using this powerful X-ray beam, we could digitally extract all the bones entombed in the burrow’s rock infill.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/395455/original/file-20210416-13-1qfvj2l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/395455/original/file-20210416-13-1qfvj2l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=390&fit=crop&dpr=1 600w, https://images.theconversation.com/files/395455/original/file-20210416-13-1qfvj2l.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=390&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/395455/original/file-20210416-13-1qfvj2l.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=390&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/395455/original/file-20210416-13-1qfvj2l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=490&fit=crop&dpr=1 754w, https://images.theconversation.com/files/395455/original/file-20210416-13-1qfvj2l.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=490&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/395455/original/file-20210416-13-1qfvj2l.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=490&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Illustration of Diictodon warren in the ancient Karoo 260 million years ago.</span>
<span class="attribution"><span class="source">Cedric Hunter, Iziko SA Museum</span></span>
</figcaption>
</figure>
<p>This meant we didn’t have to physically break the infill or damage the fossil. Even better, we discovered a second infant <em>Diictodon</em> that wasn’t visible from the surface. This reinforces the interpretation of the burrow as a brooding chamber, a conclusion that would have remained out of reach without the synchrotron.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/VpDYBcgjKJs?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">A video showing the results of the synchrotron’s work.</span></figcaption>
</figure>
<p>In all, we identified the bones of an adult and two tiny infant skeletons all lying together in a confined space. </p>
<p>Meanwhile, the end chamber of another burrow cast found in 2014 was mechanically prepared at the <a href="https://www.iziko.org.za/museums/south-african-museum">Iziko South African Museum’s</a> fossil laboratory. This revealed another adult <em>Diictodon</em> skeleton along with a tiny infant limb bone. Synchrotron imaging of the tusks and inner ear of the adult skulls indicated that they were both males.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/395421/original/file-20210416-23-iye577.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/395421/original/file-20210416-23-iye577.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/395421/original/file-20210416-23-iye577.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/395421/original/file-20210416-23-iye577.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/395421/original/file-20210416-23-iye577.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/395421/original/file-20210416-23-iye577.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/395421/original/file-20210416-23-iye577.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">A graphic representation of one of the burrows in which bones - including an infant humerus, bottom right.</span>
<span class="attribution"><span class="source">Authors supplied</span></span>
</figcaption>
</figure>
<h2>Daddy takes care of the babies</h2>
<p>This work has allowed us to demonstrate for the first time that burrows were used during breeding season as brood chambers. This is a clear case of parental care, which is a very mammalian behaviour. It shows that parental care of offspring may have predated the origin of mammals by almost 60 million years.</p>
<p>The fact that the two adult specimens are males, not females, suggests that some parental care may have been done by males, unlike in most modern mammals. We do not know the significance of this. But male parental care in modern mammals <a href="https://www.nature.com/articles/ncomms11854">enables</a> faster growth of the young and increases fecundity of the female, which can be advantageous in times of crisis. </p>
<p>Burrowing of this sort likely had benefits beyond parental care. The action may have saved mammals and their ancestors from mass extinction events countless times. For example, it enabled them to <a href="https://doi.org/10.2110/palo.2020.007">survive</a> the “Great Dying” 252 million years ago, a biological crisis that wiped out <a href="https://doi.org/10.1016/j.gr.2012.12.010">90%</a> of all living creatures, and the fall of the notorious meteorite that killed off the dinosaurs <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4213634/">66 million years ago</a>. Now we have evidence that this important, life-saving behaviour started 260 million years ago in South Africa.</p><img src="https://counter.theconversation.com/content/158645/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Roger Malcolm Harris Smith receives funding for this project from the National Research Foundation’s African Origins Platform.</span></em></p><p class="fine-print"><em><span>Julien Benoit receives funding from the DST-NRF Centre of Excellence in Palaeosciences. </span></em></p><p class="fine-print"><em><span>Vincent Fernandez is a visiting scientist at the European Synchrotron Radiation Facility. He has received grants from The Palaeontological Scientific Trust (PAST) in South Africa for previous projects.</span></em></p>These new finds indicate that Diictodon was burrowing and giving some parental care to its young. This was long thought to be unique to mammals.Roger Malcolm Harris Smith, Distinguished Professor, University of the WitwatersrandJulien Benoit, Senior Researcher in Vertebrate Palaeontology, University of the WitwatersrandVincent Fernandez, X-ray CT laboratory manager, Natural History MuseumLicensed 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/773452017-05-16T00:14:18Z2017-05-16T00:14:18ZIt’s time to celebrate Africa’s forgotten fossil hunters<figure><img src="https://images.theconversation.com/files/168887/original/file-20170511-32618-bewdt0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Local people at Tendaguru (Tanzania) excavation site in 1909 with Giraffatitan fossils.</span> <span class="attribution"><a class="source" href="http://www.welt.de/wissenschaft/article3586616/Urzeitliches-Knochenpuzzle-aus-Deutsch-Ostafrika.html">Wikimedia Commons/Public domain</a></span></figcaption></figure><p>There are few things more exciting for a professional palaeontologist than discovering fossil remains. In early 2017 I found a beautifully preserved skeleton sticking out of the ground in South Africa’s Karoo region. It was the vertebral column of a big herbivorous animal called <a href="http://www.ucmp.berkeley.edu/anapsids/pareiasauria.html">pareiasaur</a>. </p>
<p>The individual vertebral arches were accompanied by the animal’s two hip blades. Fragments of its forelimbs and some parts of its cranium were also visible. All this suggested that I’d found a skeleton nearly 2 meters long, the rest of it hidden below the ground. These 275 million years old fossils had no deformities and were easy to identify. I realised that even someone with no training in palaeontology would have easily find such eroding bones and recognised them as some giant creature’s remains.</p>
<p>This got me thinking about Africa’s earliest fossil seekers, whose identities are largely unknown. Who were they, and how did their discoveries influence our thinking about evolution? How many of their ideas were dismissed or written out of history after the arrival of colonialism and western fossil hunters on the continent? </p>
<p>It’s important to honour these people and their fossil finds, which are examples of both cultural and palaeontological heritage.</p>
<h2>Historical fossil hunting in Africa</h2>
<p>For many, the history of fossil bone discovery in Africa can’t be separated from famous European-led expeditions. Many of these happened during the 19th and 20th centuries and generated breathless headlines around the world. </p>
<p>There was the German expedition at Tendaguru (Tanzania), which yielded the extraordinary skeletons of some of the <a href="https://www.amazon.com/African-Dinosaurs-Unearthed-Tendaguru-Expeditions/dp/0253342147">biggest dinosaurs ever found</a>. American and European palaeontologists also mounted several trips to the <a href="https://link.springer.com/chapter/10.1007/978-0-387-73896-3_9">Fayum depression</a> in Egypt because it was home to mammals of all sorts and sizes some 35 million years ago.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/168366/original/file-20170508-20745-17ek8mu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/168366/original/file-20170508-20745-17ek8mu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/168366/original/file-20170508-20745-17ek8mu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/168366/original/file-20170508-20745-17ek8mu.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/168366/original/file-20170508-20745-17ek8mu.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/168366/original/file-20170508-20745-17ek8mu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/168366/original/file-20170508-20745-17ek8mu.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/168366/original/file-20170508-20745-17ek8mu.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"></a>
<figcaption>
<span class="caption">This perfectly preserved backbone actually belongs to a long extinct reptile called pareiasaur.</span>
<span class="attribution"><span class="source">Julien Benoit</span></span>
</figcaption>
</figure>
<p>These expeditions captured the public’s imagination. But the archaeological record reveals that fossils were discovered and collected <a href="http://press.princeton.edu/titles/9435.html">well before such trips</a>, by amateurs who used them in, for instance, religious rituals.</p>
<p>In her book about fossil discoveries in classical Antiquity, “<a href="http://press.princeton.edu/titles/9435.html">The First Fossil Hunters</a>”, Adrienne Mayor mentions that gigantic bones were found in Morocco as early as 300 to 400 B.C. She suspects they were fossilised elephants.</p>
<p>One of the most famous ancient fossil discoveries in Africa involved a giant tooth. Christian theologian and philosopher Saint Augustin, the bishop of what is today Algeria, found it near Utica (Tunisia) in the fourth century A.D. It proved to be a <a href="http://sp.lyellcollection.org/content/310/1/67.abstract">fossilised elephant molar</a>.</p>
<p>Saint Augustin’s discovery isn’t the oldest example of fossil collection in Africa, though. That title goes to the ancient Egyptians who collected and gathered millions of years old mammalian fossil bones and packed them in linen, likely as a <a href="https://books.google.co.za/books?id=9TwhfvU08UcC&source=gbs_book_other_versions">form of worship to Set</a>. These fossil collectors lived 3000 years ago. There’s also evidence of fossilised shark teeth that were collected and pierced to be worn as pendants in ancient Egypt, some <a href="https://books.google.co.za/books?id=9TwhfvU08UcC&source=gbs_book_other_versions">6500 years</a> ago. </p>
<h2>The search for the first fossil collectors</h2>
<p>It’s possible that fossils were recognised in Africa even earlier than this. In Congo, a site dating back 21 000 years has yielded the tooth of a fossil elephant that went extinct millions of years earlier. This <a href="https://books.google.co.za/books?id=9TwhfvU08UcC&source=gbs_book_other_versions">suggests</a> that someone stumbled upon this large fossil tooth and brought it back home, perhaps as a curio.</p>
<p>In addition, an undated Khoisan rock art site in Lesotho appears to represent <a href="http://www.tandfonline.com/doi/pdf/10.1080/10420940591008971">dinosaur footprints</a>. Fossil tracks dating back more than 200 million years ago are not uncommon in this region, and are often well exposed – lying close to the surface of the earth – so it makes sense that ancient residents would have seen and documented them. The Khoisan could well have been the first people to find fossils in Southern Africa. </p>
<p>Though this hypothesis is still <a href="http://www.davidpublishing.com/davidpublishing/Upfile/10/18/2013/2013101882378185.pdf">hotly debated</a>, these drawings are accompanied by cave paintings which suggest the Khoisan interpreted these footprints as belonging to a race of <a href="http://www.tandfonline.com/doi/pdf/10.1080/10420940591008971">giant, flightless birds</a>. Today, most scientists consider birds to be dinosaurs’ closest living relatives. This would imply that Khoisans ancestors had a remarkable sense of scientific reconstruction, even though no framework for evolution had yet been described.</p>
<h2>Before Darwin</h2>
<p>The Khoisan weren’t the only people in Africa thinking way ahead of the Darwinian curve. A number of Muslim scholars from the Middle East and North Africa made very explicit, <a href="https://www.thevintagenews.com/2016/08/27/priority-first-theory-evolution-600-years-older-darwin/">farsighted statements centuries before Darwin</a>.</p>
<p>For example, a Tunisian scholar named Ibn Khaldun, stated as early as 1377 that “the higher stage of man is reached from the world of the monkeys, in which both sagacity and perception are found.” He was probably inspired by his predecessor, the Persian Ibn Miskawayh (932-1030), who stated in the Brethren of Purity that “Animalilty […] finally reaches the frontier of humanity with the Ape which is just a degree below Man in the <a href="http://pu.edu.pk/images/journal/uoc/PDF-FILES/%2811%29%20Dr.%20Sultan%20Shah_86_2.pdf">scale of evolution”</a>.</p>
<p>It’s very likely that Darwin didn’t know about these ancient discoveries and medieval authors since they are not mentioned in any of his biographies or works. But the very fact that they exist illustrates Africa’s formidable potential to influence and develop palaeontological research. </p>
<p>The challenge now is to build upon this heritage and raise awareness about these long-forgotten discoveries and theorists. This is an important way to motivate a new generation of African fossil researchers.</p><img src="https://counter.theconversation.com/content/77345/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>Africa has one of the world’s richest fossil records, and evidence suggests that amateurs collected really important fossils long before professionals arrived on the scene.Julien Benoit, Postdoc in Vertebrate Palaeontology, University of the WitwatersrandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/713462017-01-18T15:01:37Z2017-01-18T15:01:37ZWhen it comes to big finds, scientists need more than just luck and chance<figure><img src="https://images.theconversation.com/files/152838/original/image-20170116-8769-cublv1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The author's backpack was hiding this almost complete therapsid fossil. Was finding it all down to luck?</span> <span class="attribution"><span class="source">Julien Benoit</span></span></figcaption></figure><p>The history of science abounds with stories about discoveries made by chance. One of the most famous cases, involves French physicist <a href="http://www.nobelprize.org/nobel_prizes/physics/laureates/1903/becquerel-bio.html">Antoine Henri Becquerel</a>, who accidentally discovered radioactivity by leaving a piece of granite on photographic paper in a drawer of his desk. Another, is the story of Scottish biologist <a href="http://www.nobelprize.org/nobel_prizes/medicine/laureates/1945/fleming-bio.html">Alexander Fleming</a>, who forgot his bacterial cultures at home when he went on holiday. They rotted – and Fleming discovered penicillin.</p>
<p>These charming stories showcase science’s most human aspect: men and women who make lucky mistakes that can save lives or change the world. Even scientists are happy to believe these tales, though they don’t do much justice to our colleagues’ expertise. </p>
<p>But is this really the way science works? Can anybody, scientist or not, rely on luck to make important discoveries? My own “lucky strike” as a palaeontologist – finding a nearly complete fossil of a pre-mammalian ancestor – helped me to understand that good science isn’t rooted in chance. It’s based on people with expertise being in the right place at the right time, equipped with enough knowledge to know what they’re looking at. </p>
<h2>A fossil find</h2>
<p>My moment of “luck” occurred in South Africa’s Karoo in 2015. I’d been invited to join an international team of palaeontologists led by Professor Bruce Rubidge and Dr Michael Day from the University of the Witwatersrand in Johannesburg. We came from Europe, South America and Africa to look for the fossils of <a href="http://www.newworldencyclopedia.org/entry/Therapsid">pre-mammalian therapsids</a>, which date back around 260 million years.</p>
<p>The Karoo is a semi-arid desert mostly populated by sheep and thorny bushes that covers a huge swathe of South Africa between Johannesburg and Cape Town. Hundreds of millions of years ago it was covered with lakes, rivers, dense primeval vegetation. Large reptile-like beasts roamed this landscape.</p>
<p>On the day in question we were fossil hunting between the towns of Sutherland and Fraserburg. There were rich pickings: Bruce and Michael had identified an area filled with fossil remains. So, we were in the right place. And, crucially, my shoes were totally wrong for the Karoo. Between the thorns and the heat, the plastic of my shoes had melted and their toes had been ripped open by thorns.</p>
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<a href="https://images.theconversation.com/files/152839/original/image-20170116-8806-x8ur11.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/152839/original/image-20170116-8806-x8ur11.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/152839/original/image-20170116-8806-x8ur11.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=398&fit=crop&dpr=1 600w, https://images.theconversation.com/files/152839/original/image-20170116-8806-x8ur11.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=398&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/152839/original/image-20170116-8806-x8ur11.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=398&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/152839/original/image-20170116-8806-x8ur11.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/152839/original/image-20170116-8806-x8ur11.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/152839/original/image-20170116-8806-x8ur11.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Alexander Fleming.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>So I sat down on an outcrop of sandstone that formed a natural bench, putting my backpack down next to me. A brief burst of rain brought a bunch of critters out from their hiding places to drink; an astonishing spectacle. When the sun returned, I felt ready to carry on. I picked up my backpack – and saw the beautiful, nearly complete fossilised therapsid skeleton it had been covering.</p>
<p>It was 30cm long and in great condition, and it has been right next to me, under my backpack all the time ! I couldn’t contain my enthusiasm, exclaiming, “How lucky am I?”. And that’s when I started thinking about “luck” in the context of scientific discovery. Was I that lucky after all?</p>
<h2>Serendipity and science</h2>
<p>Bruce and Michael, two experts in their field, had chosen our prospecting spot carefully based on what they knew. They had sent out a complete team of palaeontologists who knew what to look for. This doesn’t look like luck to me: it was probability in action. </p>
<p>This is the very essence of what we call serendipity: the art of creating the good intellectual, scientific and experimental context for a “fortuitous” discovery to happen. Fleming may well have discovered penicillin by chance, but the conditions were right because he had all the equipment and specimens he needed.</p>
<p>Becquerel would never have realised what he’d found if he hadn’t been carefully studying natural fluorescence. His existing knowledge allowed him to recognise a major discovery.</p>
<p>Maybe I discovered this skeleton by chance – or perhaps I found it because that was what we were looking for, in the right place and with the right people.</p>
<p>My humble fossil was certainly far from the level of Fleming and Becquerel’s discoveries. But it offered a valuable reminder that pure luck can’t account for scientific breakthroughs. Hours of work, and countless people and money are invested to create the right opportunity for discoveries to happen. Serendipity happens when scientists create their own luck.</p><img src="https://counter.theconversation.com/content/71346/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Julien Benoit receives funding from PAST and its scatterlings projects; the NRF; and the DST-NRF Centre of Excellence in Palaeosciences (CoE in Palaeosciences).</span></em></p>Good science isn’t rooted in chance. It’s based on people with expertise being in the right place at the right time, equipped with enough knowledge to know what they’re looking at.Julien Benoit, Postdoc in Vertebrate Palaeontology, University of the WitwatersrandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/684542016-11-13T06:58:17Z2016-11-13T06:58:17ZWhat our ancestors’ third eye reveals about the evolution of mammals to warm blood<figure><img src="https://images.theconversation.com/files/145052/original/image-20161108-16702-ycblag.JPG?ixlib=rb-1.1.0&rect=1060%2C243%2C3951%2C3441&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The fossilised skull of an Odontocyclops displays its pineal foramen.
</span> <span class="attribution"><span class="source">Nkansahrexford (Own work) via Wikimedia Commons</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>French philosopher René Descartes <a href="http://plato.stanford.edu/entries/pineal-gland/">believed</a> that the pineal gland, a tiny button of neurons located in the depth of our brain, was the seat of the soul.</p>
<p>Today, thanks to palaeontology, genetic and developmental studies, we know that it is actually the evolutionary relic of a long-vanished organ, the third eye. This is also known as the pineal eye and is a receptor located on the top of the head. Many existing reptiles such as monitor lizards, some iguanas and the <a href="http://www.doc.govt.nz/nature/native-animals/reptiles-and-frogs/tuatara/">tuatara</a> still have a pineal eye.</p>
<p>All reptiles that still have the pineal eye today are “cold blooded”; they have what’s known as an ectotherm metabolism. Modern mammals – which of course have “warm blood” or an endotherm metabolism – don’t have a pineal eye. </p>
<p>Our group of researchers at the University of the Witwatersrand wondered whether being able to pinpoint when pre-mammalian species lost their pineal eye might unlock the secret of when “warm bloodedness” become a mammalian hallmark. That’s what drove <a href="https://www.app.pan.pl/archive/published/app61/app002192015.pdf">an ambitious study</a> using fossil remains from South Africa’s Karoo region. </p>
<p>We were proved right: our research revealed that mammalian ancestors likely shifted from “cold” to “warm” blood 246 million years ago. This was 10 million years before the first dinosaur even appeared.</p>
<h2>Why have a third eye?</h2>
<p>As with a regular eye, the pineal eye is made up of a cornea, a lens and a retina. Our paired eyes and the reptilian pineal eye are also very similar in terms of embryological development and the genes expressed during this. The pineal eye differs from a regular eye, though, in that it’s usually covered by a thick and large scale and can differentiate between light and dark only.</p>
<p>Our regular eyes can also see variations between light and dark, day and night – so what’s the point of having an organ as redundant as the pineal eye? <a href="https://books.google.co.za/books?id=pkDgJBd4O6oC&printsec=frontcover&source=gbs_ge_summary_r&cad=0#v=onepage&q&f=false">Research</a> shows that in reptiles the pineal eye acts as a calendar. It can see days getting longer and nights getting shorter, and the reverse, and so tells the brain how seasons are changing. As a consequence, it monitors most life cycles such as sleep and reproduction rhythms. </p>
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<a href="https://images.theconversation.com/files/145388/original/image-20161110-25090-ovuv8w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/145388/original/image-20161110-25090-ovuv8w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/145388/original/image-20161110-25090-ovuv8w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/145388/original/image-20161110-25090-ovuv8w.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/145388/original/image-20161110-25090-ovuv8w.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/145388/original/image-20161110-25090-ovuv8w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/145388/original/image-20161110-25090-ovuv8w.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/145388/original/image-20161110-25090-ovuv8w.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">Komodo dragons and some other reptiles still have a pineal eye.</span>
<span class="attribution"><span class="source">Arturo de Frias Marques (Own work) via Wikimedia Commons</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p><a href="https://www.jstor.org/stable/30156149?seq=1#page_scan_tab_contents">Surgical experiments</a> on lizards have also shown that removing the pineal eye affects their capacity to regulate their body temperature, a process called thermoregulation. </p>
<p>This is fascinating since our pre-mammalian ancestors did have a pineal eye and lost it in the course of their evolution toward a more mammalian condition. This suggested that by following the reduction and disappearance of the pineal eye through millions of years, we might be able to point out the time when our ancestors became “warm blooded”.</p>
<h2>A gateway to ancient metabolism</h2>
<p>The pineal eye’s evolution is easy to study. It has an unmistakable bony correlate, the pineal foramen. This is a tube that pierces the skull roof for the pineal eye and nerve. </p>
<p>Most of our ancestors, the pre-mammalian therapsids, had such a foramen on the top of their heads, as can be seen in their fossilised skulls, and thus had a pineal eye. It’s reasonable to assume that this organ fulfilled a similar role in thermoregulation as it does in today’s reptiles.</p>
<p>By checking for the pineal foramen in fossils, we reasoned, it would be possible to trace back the transition from a “reptile-like” to a “mammal-like” metabolism in the lineage that eventually led to mammals.</p>
<p>So our team of palaeontologists and neurologists checked for the pineal foramen in more than 600 skulls. These were all found in the <a href="https://www.wits.ac.za/esi/fossil-collections/">Karoo’s incredibly rich fossil-bearing deposits</a> and dated back to between 300 million and 200 million years ago. </p>
<p>That’s an important time period, since South Africa was situated close to the South Pole at that time thanks to <a href="http://www.varsityfield.com/uploads/1/3/0/5/13050122/theme_11.pdf">continental drift</a>. The climate, then, was much colder and drier, and the contrast between the country’s seasons was greater than today. This implies that species with “cold blood” must have had a pineal eye to help them regulate their body temperature. </p>
<p>To find a species that lived under such harsh conditions without a pineal foramen would strongly suggest that this species was “warm blooded” and that a pineal eye was no longer required to survive. </p>
<h2>An evolutionary step forward</h2>
<p>We found that the pineal foramen was present in most pre-mammalian therapsids before 260 million years ago. After this the feature was increasingly absent. This suggests the pineal eye became dispensable and wasn’t needed for survival any more. </p>
<p>The increasing loss of the pineal foramen occurred in two lineages. One of these, the <a href="https://global.britannica.com/animal/cynodont">cynodonts</a>, led to mammals. In their case, the pineal foramen disappeared entirely 246 million years ago. It’s then, we believe, that the transition from “cold blood” to “warm blood” was achieved.</p>
<p>More work needs to be done to test this evolutionary scenario, but if it proves true it would mean that mammals had likely already evolved one of the key adaptations that enabled them to survive for more than 200 million years through the reign and extinction of dinosaurs and two mass extinctions to the present day.</p><img src="https://counter.theconversation.com/content/68454/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Julien Benoit receives funding from 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>Mammals’ ancestors had a third eye and the fossil record of its disappearance tells us the story of the evolution of one of our most important features: warm blood.Julien Benoit, Postdoc in Vertebrate Palaeontology, University of the WitwatersrandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/673172016-11-10T15:34:38Z2016-11-10T15:34:38ZConsidering the technical readiness of South Africa to support the shale gas industry<figure><img src="https://images.theconversation.com/files/145066/original/image-20161108-16685-5ff7il.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">South Africa's Karoo region, in the south west of the country, is thought to have significant reserves of shale gas.</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>The discovery and exploitation of very large shale gas reserves in countries like the United States have transformed <a href="http://onlinelibrary.wiley.com/doi/10.1002/ente.201402177/abstract">the energy market</a>. South Africa may also possess potentially large resources of shale gas. This could have a significant positive impact on the country’s energy balance should it be decided to exploit these resources.</p>
<p>The exploitation of these key energy resources might also have a significant social, economic or environmental impact while also presenting considerable technical challenges.</p>
<p>Given the recent challenges the country is facing in terms of <a href="http://www.gov.za/issues/energy-challenge">energy supply</a>, the possibility of exploiting shale gas deposits for power generation is of current significance. Shale gas also presents other downstream opportunities. Some include providing a key resource for the production of liquid fuels and chemicals, or enabling the development of a domestic market for gas as a cleaner <a href="http://www.mckinsey.com/global-themes/middle-east-and-africa/south-africas-bold-priorities-for-inclusive-growth">energy resource</a>.</p>
<h2>Uncertainties</h2>
<p>South Africa’s Karoo region, in the south west of the country, is thought to have significant reserves of shale gas. Recently there has been considerable interest from the government and various companies like Shell, Falcon and Bundu to develop a shale gas industry there. <a href="http://research.assaf.org.za/handle/20.500.11911/14">Considerable uncertainties</a> exist regarding the extent of these reserves and the geology at depths where they are typically found. These and other uncertainties and constraints include the following.</p>
<ul>
<li><p>The quantum of shale gas in the Karoo is still unclear: estimates range between <a href="http://www.eia.gov/todayinenergy/detail.php?id=11611">20 and 400 trillion cubic feet</a>. None of these reserves has yet been proven.</p></li>
<li><p>There are also constraints relating to geographical regions. For example, no fracking may take place in the vicinity of the <a href="https://www.ska.ac.za/">Square Kilometre Array station project</a>. The project consists of the largest network of radio telescopes ever built.</p></li>
<li><p>Ensuring that no hydraulic fracturing takes place at depths less than 1500m to protect groundwater resources will also reduce the geographical area of interest.</p></li>
<li><p>Shale gas exploitation requires the use of relatively large quantities of water. Given that potable groundwater should preferably not be used for any such exploitation, greater clarity is needed on the availability of deep-level saline water. This is considered to be acceptable for use in hydraulic fracturing.</p></li>
<li><p>Baseline studies need to be carried out to ascertain with greater certainty the environment at depths greater than 3 km underground. Such baseline studies should also ensure that there is a clear understanding of the status of the human and natural environments before any fracking commences.</p></li>
<li><p>South Africa has a serious shortage of the high-level skills that would be required to implement such an industry. Strategies need to be set in place to develop skills to ensure sustainable development of the shale gas industry.</p></li>
<li><p><a href="http://research.assaf.org.za/handle/20.500.11911/14">International experience</a> has highlighted the critical need to have all the necessary legislative and regulatory structures in place. But also, a sufficient number of regulators with the required skills before a shale gas industry is launched.</p></li>
<li><p>The implementation of a shale gas industry in an area like the Karoo may have a significant socio-economic impact on the local population. Similar concerns have been expressed in studies especially from <a href="http://www.scienceadvice.ca/uploads/eng/assessments%20and%20publications%20and%20news%20releases/shale%20gas/shalegas_fullreporten.pdf">Canada</a> and <a href="http://www.acola.org.au/index.php/projects/securing-australia-s-future/project-6">Australia</a>. So it is important to ensure that there is a full understanding of the potential impact. Plans must be developed to manage them.</p></li>
</ul>
<p>Resolution of these uncertainties requires extensive and ongoing consultation with all relevant parties. As such government has an important role to play as an honest broker of key information.</p>
<h2>Risk and challenges</h2>
<p>These uncertainties point to specific risks and challenges associated with the establishment of a shale gas industry in South Africa. This will require government to create an enabling environment to encourage investment in the industry while also ensuring that the state and local communities benefit. It is also critical that there is clarity regarding the pricing structures that may prevail. This is crucial when the industry begins to exploit the shale gas reserves, and obviously requires a clearer understanding of the potential quantum of the known reserves.</p>
<p>Establishing a shale gas industry presents complex technical and economic challenges, and implementation will require a whole-of-government <a href="http://research.assaf.org.za/handle/20.500.11911/14">approach</a>.</p>
<p>A structure at government level to facilitate and coordinate all the activities relating to the industry is recommended. This could coordinate the awarding of licences by various government departments and would have oversight of the activities of the regulators.</p>
<p>Awarding a production licence should proceed after satisfactory completion of terms associated with an exploration licence. This would require operators to demonstrate compliance of processes with legislation.</p>
<p>It is evident that before a shale gas industry in South Africa is implemented, important baseline studies need to be done. This will determine both the exact status quo prior to the commencement of a shale gas industry and the technical, social and economic consequences of such a development.</p><img src="https://counter.theconversation.com/content/67317/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Cyril O'Connor does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Shale gas holds considerable advantages. But there are still a number of uncertainties around whether South Africa is ready for such a bold step.Cyril O'Connor, Emeritus Professor Department of Chemical Engineering Faculty of Engineering and the Built Environment, University of Cape TownLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/655942016-10-26T17:43:11Z2016-10-26T17:43:11ZHow a climate crisis can lead farmers to joint planning and response<figure><img src="https://images.theconversation.com/files/143046/original/image-20161025-31486-1kr9hmt.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Droughts in South Africa has led to coordinated joint planning and partnerships to combat the problem.</span> <span class="attribution"><span class="source">Stephanie Midgley</span></span></figcaption></figure><p>There is nothing like a major climate disaster to raise interest in the problem of climate change among farming communities. Farmers in many parts of the world have, in the last decade, strained under extended droughts and intense flooding. But farmers in southern Africa last experienced a major drought 30 years ago – and memories tend to fade – until the current devastating <a href="http://www.nstf.org.za/wp-content/uploads/2016/06/Agri-SA-Drought-Report_CS4.pdf">drought hit</a> the farming community. </p>
<p>Farmers are deeply optimistic people. They have to be, considering the huge numbers of risks they have to deal with. And climate change is usually not anywhere near the top of their list of priority challenges. This seems strange to climate scientists, whose work shows clearly that the agricultural sector is one of the most vulnerable sectors to <a href="http://www.sanbi.org/biodiversity-science/state-biodiversity/climate-change-and-bioadaptation-division/ltas">climate change</a>, particularly in water-scarce regions. </p>
<p>The current severe <a href="http://www.nstf.org.za/wp-content/uploads/2016/06/Agri-SA-Drought-Report_CS4.pdf">drought</a> appears to have made the penny drop and role players are scrambling to deal with the crisis while assessing what needs to be done to create greater resilience. The message that more frequent climate disasters like droughts can be expected in future is also being taken seriously.</p>
<h2>Constructive discussions</h2>
<p>A team of researchers completed an <a href="http://www.greenagri.org.za/smartagri-2/smartagri-plan/">assignment</a> from South Africa’s Western Cape Government to develop a provincial climate change response strategy and to implement a framework for the agricultural sector. The SmartAgri Plan project <a href="http://www.acdi.uct.ac.za/research/smartagri">began in August 2014</a>, many months before the first signs of the drought appeared. But at the end of the project, in March 2016, the province and country were in the grip of a two-year drought.</p>
<p>This fortuitously provided an environment ripe for engagement on the issue of climate change and how to respond to it. From the start, the project remit was to engage thoroughly across the sector – and related sectors like water and environment – and across the province. The plan was to find out what farmers, government and others are already doing to deal with climate risks. But also, to find out what approaches and measures are needed to build climate resilience.</p>
<p>During the first rounds of engagement it became clear that dialogue between government and the farming communities is sensitive to issues of mistrust and misunderstanding. This emanates from past injustices and present policy uncertainties. The team was surprised at the willingness of all participants to hear each other and try find solutions which benefit everyone, in the context of farming and non-farming problems.</p>
<p>There was real concern for the fate of the most vulnerable farmers, often smallholder communities and new farmers, who needed more support. Equally, all types of farmers generally place a high premium on good catchment management, water management and fire management. Their role in platforms like water user associations and fire protection associations was acknowledged.</p>
<h2>A coordinated response</h2>
<p>This made a valuable contribution to the development of a plan which represents a road map for an integrated and inclusive response across a number of time scales. It is supported by scientific and local knowledge and experience, linking top-down policy guidance with practical bottom-up perspectives. Critically, disaster risk reduction and management is prioritised as a discrete strategic focus area needing greater attention. If this plan is well-resourced for implementation it will strengthen the ability of the sector to plan for and manage multiple interacting climate stresses and contribute to reducing vulnerability.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/143047/original/image-20161025-31462-1ymsv0v.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/143047/original/image-20161025-31462-1ymsv0v.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/143047/original/image-20161025-31462-1ymsv0v.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/143047/original/image-20161025-31462-1ymsv0v.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/143047/original/image-20161025-31462-1ymsv0v.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/143047/original/image-20161025-31462-1ymsv0v.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/143047/original/image-20161025-31462-1ymsv0v.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/143047/original/image-20161025-31462-1ymsv0v.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"></a>
<figcaption>
<span class="caption">It is crucial for collaboration to adopt approaches and measures to build climate resilience.</span>
<span class="attribution"><span class="source">Stephanie Midgley</span></span>
</figcaption>
</figure>
<p>So far so good. Then, towards the end of 2015 and first half of 2016, the drought hit with a vengeance across the region especially the Western Cape’s west coast and central Karoo (a semi-desert in the southern interior of South Africa). Crop harvests failed with losses of 200 000 tonnes of <a href="http://www.greenagri.org.za/smartagri-2/wcdoa-drought-dialogue-2016/">wheat</a> (50-100% per farm), 230 ha of potatoes and 15% of fruit, and numerous livestock. The knock-on impact was up and down the agricultural value chain, and for farming communities struggling with unemployment, was critical. </p>
<p>Relief was provided in the form of fodder assistance to the most desperate farmers, to feed around 17 000 <a href="http://www.greenagri.org.za/smartagri-2/wcdoa-drought-dialogue-2016/">cattle</a>. The Western Cape provincial government convened a two-day provincial drought dialogue with all involved in June 2016. The aim was to discuss what else the provincial government could do to strengthen the response to the current and future droughts. </p>
<p>Agreement was reached on a set of 32 high priority interventions with further prioritisation of five actions. These focus on bridging finance for farmers to keep farmers on the land, optimising water usage, accurate drought forecasts, a social security net for vulnerable communities affected by the drought, and revisiting water management and policies currently hampering new infrastructure.</p>
<h2>Looking ahead</h2>
<p>Interestingly, the drought dialogue priorities correspond closely with the SmartAgri Plan. Rather than being confined to the strategic focus area on disaster management, they were spread widely across other focus areas as well. They intersected strongly with natural resources like, soil and water management. They focused on proactive joint planning and coordination, information and communications, regulatory and financial barriers, and social vulnerability. </p>
<p>The role of government in creating a cooperative and supportive environment emerged as the key requirement for building resilience. The provincial government has taken the recommendations forward into further planning and implementation, together with the SmartAgri Plan.</p>
<p>There is certainly value in bringing all involved to the discussions. Government officials, farmers and their leadership, and others like water and conservation managers come together around a table. They jointly built strategies around how to respond to current and future climate challenges. The drought has provided an opportunity to focus minds, acknowledge the urgency of action and identify priorities.</p>
<p>It has also reinforced the understanding that coordinated joint planning and partnerships which enable the much needed shift from typical responses to prevention are required. Everyone would prefer the building of greater resilience to climate stress and disasters compared to the current unsustainable reliance on government relief. </p>
<p>The time to make it happen is now. And hopefully the role players will keep talking and listening. This will build capital based on trust and a common vision of a shared future.</p><img src="https://counter.theconversation.com/content/65594/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Stephanie Midgley receives funding from the Western Cape Department of Agriculture. </span></em></p>Drought is a problem in South Africa and it affects farmers. As a result, farmers and government are working together to develop strategies.Stephanie Midgley, Researcher and Project Manager in Agriculture, Food Security and Climate Change, University of Cape TownLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/640592016-09-26T19:07:15Z2016-09-26T19:07:15Z3D technology brings a lost mammalian ancestor back to life<figure><img src="https://images.theconversation.com/files/134406/original/image-20160817-3592-11nn3qp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A 3D model of the long-lost Scalopocynodon gracilis skull.</span> <span class="attribution"><span class="source">Evolutionary Studies Unit, Wits University</span></span></figcaption></figure><p>At the very beginning of the 1960s, a South African palaeontologist embarked on a series of ambitious works. Dr A.S. Brink wanted to better understand the anatomy and evolution of humans’ pre-mammalian ancestors, the <a href="http://www.newworldencyclopedia.org/entry/Therapsid">therapsids</a>. </p>
<p>Brink worked with therapsid skulls found in South Africa’s Karoo region. He ground the skulls at thin and regular intervals to assess their internal cranial anatomy. The technique, known as serial grinding, was commonly used at the time. </p>
<p>As he neared the end of the process on one of the skulls Brink realised that he had uncovered a unique specimen. The skull represented a <a href="http://blog.everythingdinosaur.co.uk/blog/_archives/2011/09/23/4908360.html">holotype</a>, which is the single specimen used in the definition of any new species. But by then it was too late.</p>
<p>More than 50 years later, we were among a group of scientists who followed in Brink’s footsteps. Our task was <a href="http://palaeo-electronica.org/content/2016/1478-reconstructing-scalopocynodon">to recreate</a> this unique specimen. Technology has moved on enormously in the last half century, so we were able to use 3D renderings and 3D printing – and one of our mammalian ancestors was reborn.</p>
<h2>Historical techniques</h2>
<p>South Africa was a good place for Brink’s work. The country’s Karoo region is home to <a href="https://theconversation.com/how-looking-250-million-years-into-the-past-could-save-modern-species-60338">a wealth</a> of therapsid fossils, making it an important place to study the ancestry of mammals. </p>
<p>Brink was not the first palaeontologist to use serial grinding. The technique emerged at the beginning of the 20th century. Before then scholars had to wait for the discovery of naturally preserved casts of internal structures, like the mold of the “fossil brain” of the <a href="http://humanorigins.si.edu/evidence/human-fossils/fossils/taung-child">Taung Child</a>, <em>Australopithecus africanus</em>. Or they had to break fossils open.</p>
<p>With its introduction, serial grinding became the only fully controlled way to access the “interior” of fossils. Because of their abundance, South African therapsids were among the first fossils to be studied using this new, revolutionary approach. Sadly, their abundance turned out to be a curse.</p>
<h2>Accidental destruction</h2>
<p>In 1961, Dr Brink started the serial grinding study of a well preserved skull. At this stage, he thought the specimen belonged to a common form of therapsid. </p>
<p>But during the process, the sections revealed anatomical structures that suggested the specimen may actually represent a new species of fossil therapsid previously unknown to science. By then it was too late to save the fossil: it had already been mostly ground down. Brink tried to compensate by making a very thorough and accurate description and drawings of the specimen. He named it <a href="http://wiredspace.wits.ac.za/handle/10539/16091"><em>Scalopocynodon gracilis</em></a>.</p>
<p>As in zoology, the designation of type specimens is the most critical step when naming a new species in palaeontology. This type specimen, called a holotype, is meant to serve as an anatomical reference for future comparative works. A new species can’t be recorded without a holotype. So this ground specimen was particularly important: it constituted the holotype of <em>Scalopocynodon gracilis</em>. </p>
<p>Sadly this valuable and irreplaceable piece of South Africa’s heritage and evidence of the evolution of pre-mammalian therapsids was lost. The irony is that it was destroyed by the very author of the species.</p>
<p><em>Scalopocynodon</em> was considered dead and forgotten – until 2016.</p>
<h2>Recreating our ancestor in 3D</h2>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/134407/original/image-20160817-3608-1fzwxbo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/134407/original/image-20160817-3608-1fzwxbo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/134407/original/image-20160817-3608-1fzwxbo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=587&fit=crop&dpr=1 600w, https://images.theconversation.com/files/134407/original/image-20160817-3608-1fzwxbo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=587&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/134407/original/image-20160817-3608-1fzwxbo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=587&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/134407/original/image-20160817-3608-1fzwxbo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=738&fit=crop&dpr=1 754w, https://images.theconversation.com/files/134407/original/image-20160817-3608-1fzwxbo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=738&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/134407/original/image-20160817-3608-1fzwxbo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=738&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">Evolutionary Studies Institute, Wits University</span></span>
</figcaption>
</figure>
<p>It’s then that a team from the Evolutionary Studies Institute at Johannesburg’s University of the Witwatersrand retrieved some of Dr Brink’s drawings of the <em>Scalopocynodon gracilis</em> from 1961. These drawings represent each thin section ground by Brink. Their detail presented us with an unprecedented opportunity to virtually reconstruct the long lost specimen of <em>Scalopocynodon gracilis</em>.</p>
<p>The drawings were digitised. Then, using cutting edge software and innovative computer-based technology, every slice was digitally reassembled in a single stack. This allowed us to reconstruct a 3D model of the original skull. Afterwards a physical model of <em>Scalopocynodon</em> was printed in 3D so we could recreate a life-sized reconstruction of this specimen.</p>
<p>To our knowledge, this is the first time 3D technology has been used to recreate and print in 3D a serially ground fossil vertebrate (though it is quite often used in invertebrates palaeontology).</p>
<p>This is a great initiative for South African heritage conservation. These techniques can be used on other fossils lost through serial grinding. </p>
<h2>Breathing new life</h2>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/VAUfDJ4xVmc?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Recreating a fossil using 3D technology is painstaking work.</span></figcaption>
</figure>
<p>The 3D printed skull, serving as a holotype, could also help to breathe new life into this mysterious specimen. Taxonomists can now study it and one day might be able to say definitively that Brink was right: <em>Scalopocynodon gracilis</em> was indeed different from any other therapsid.</p><img src="https://counter.theconversation.com/content/64059/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Julien Benoit receives funding from from 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><p class="fine-print"><em><span>Sandra Jasinoski received postdoctoral funding from the DST-NRF Centre of Excellence in Palaeosciences. </span></em></p>An old technique to explore the inside of fossils unfortunately ended up destroying some unique specimens. New technology has been used to reconstruct one such fossil.Julien Benoit, Postdoc in Vertebrate Palaeontology, University of the WitwatersrandSandra Jasinoski, Postdoc in Palaeontology, University of the WitwatersrandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/603382016-06-07T14:04:21Z2016-06-07T14:04:21ZHow looking 250 million years into the past could save modern species<figure><img src="https://images.theconversation.com/files/125538/original/image-20160607-15031-aifndq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A Permo-Triassic boundary site near Bethulie in South Africa's Free State province. </span> <span class="attribution"><span class="source">Supplied</span></span></figcaption></figure><p><em>More than 250 million years ago, something huge happened to the Earth: the <a href="http://science.nasa.gov/science-news/science-at-nasa/2002/28jan_extinction/">Permo-Triassic Mass Extinction</a> (PTME), which wiped out almost all of the planet’s species. Now a group of scientists has <a href="http://www.nature.com/articles/srep24053">uncovered</a> important details about how the event’s survivors adapted in a harsh, drought-stricken stretch of South Africa. The Conversation Africa’s science and technology editor Natasha Joseph asked lead researcher Dr Jennifer Botha-Brink to explain what she and her colleagues have learnt – and what this might teach us about species’ adaptation to climate change.</em></p>
<p><strong>Lots of research has been done about this period and its impact. What was your research trying to understand, specifically?</strong></p>
<p>There have been five major mass extinctions in Earth’s history and the PTME was by far the most catastrophic, killing 70% of all terrestrial species and somewhere between 80% and 96% of all marine species. The environment changed from a world with abundant vegetation, large meandering rivers and a temperate climate to a highly seasonal, drought-stricken, unpredictable environment. The world’s ecosystems did not fully recover until some five million years after the extinction event. </p>
<p>The aim of our research was to discover the changes, if any, that occurred in vertebrate life histories across the PTME. In other words, how did the survivors adapt to the harsh, unpredictable, drought-stricken post-extinction environment? To try and answer this question, we compared the growth patterns of Permian (pre-extinction) and Triassic (post-extinction) therapsids – they were the ancient ancestors of mammals – by looking at their bone microstructure. </p>
<p>The bone microstructure, or histology, of extinct vertebrates gives a unique view on how they lived. It provides information about how quickly an animal grew, the manner in which it grew, when it matured – that’s the age it was at skeletal and possibly reproductive maturity – and how old it was when it died. This information allows us to reconstruct the animal’s life history.</p>
<p>Comparing the life histories of therapsids that lived before and after the extinction allowed us to identify differences in the Early Triassic animals that may have helped them survive the PTME. Our results help explain how some species that thrive in post-extinction environments, such as the therapsid <a href="http://study.com/academy/lesson/lystrosaurus-facts-lesson-quiz.html">Lystrosaurus</a>, not only survived but spread to all areas of the globe and became the most abundant vertebrate after the PTME.</p>
<p><strong>Your research was focused on therapsids that had occurred in South Africa’s Karoo Basin. How large an area is that, and why did you choose it as the site for your work?</strong></p>
<p>The South African Karoo Basin contains the best, most complete terrestrial record of the PTME. It covers some 730,000km² of the interior of South Africa. Thousands of therapsid fossils have been found in these strata, providing a complete fossil record through the Permo-Triassic boundary. There was enough material from many different therapsid species to allow us to obtain the information required for this type of analysis. It is the best place for studying the PTME and its influence on animal and plant life histories.</p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/125400/original/image-20160606-13043-79271p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/125400/original/image-20160606-13043-79271p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/125400/original/image-20160606-13043-79271p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=350&fit=crop&dpr=1 600w, https://images.theconversation.com/files/125400/original/image-20160606-13043-79271p.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=350&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/125400/original/image-20160606-13043-79271p.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=350&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/125400/original/image-20160606-13043-79271p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=440&fit=crop&dpr=1 754w, https://images.theconversation.com/files/125400/original/image-20160606-13043-79271p.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=440&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/125400/original/image-20160606-13043-79271p.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=440&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">An illustration of the Lystrosaurus.</span>
<span class="attribution"><span class="source">Maggie Lambert-Newman</span></span>
</figcaption>
</figure>
<p><strong>How did you extract the data you needed? And what was it you were looking for in those fossils – what stories did they tell you?</strong></p>
<p>Our analysis focused on fossil bone microstructure and body size measurements. Limb bones were sectioned using specialised cutting and grinding equipment. Thin slivers of the fossil bone were then fixed to glass slides and examined under a microscope. Although the organic components of the bone have long since disappeared, the orientation of the bone tissue fibres, the spaces for marrow, blood vessels and bone cells remain intact. This allows us to compare growth patterns and rates between different species. </p>
<p>We also obtained body size data by measuring the skull lengths of as many therapsid specimens as possible. These measurements were used to compile body size distributions so we could compare the demographics between Permian and Triassic therapsid species. All the data were then combined to assess the ecology of Permian and Triassic therapsids. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/125401/original/image-20160606-13040-1wiwypt.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/125401/original/image-20160606-13040-1wiwypt.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/125401/original/image-20160606-13040-1wiwypt.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=1029&fit=crop&dpr=1 600w, https://images.theconversation.com/files/125401/original/image-20160606-13040-1wiwypt.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=1029&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/125401/original/image-20160606-13040-1wiwypt.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=1029&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/125401/original/image-20160606-13040-1wiwypt.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1293&fit=crop&dpr=1 754w, https://images.theconversation.com/files/125401/original/image-20160606-13040-1wiwypt.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1293&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/125401/original/image-20160606-13040-1wiwypt.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1293&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A Lystosaurus skeleton, which was examined to understand how the species adapted to a massive extinction event.</span>
<span class="attribution"><span class="source">Jennifer Botha-Brink</span></span>
</figcaption>
</figure>
<p>We also used the data to create a theoretical model showing what kind of features would have helped the post-extinction therapsids to survive. The bone microstructure and body size data showed that Early Triassic therapsids grew quickly to skeletal and reproductive maturity and then died at young ages. The simulations of population growth supported our results by showing that reproducing at young ages would indeed have helped the survivors to persist in the harsh, unpredictable post-extinction environment.</p>
<p><strong>Your work focused on extinct species. What are its applications today? What can it tell us about how species might cope with another big “die-out”?</strong></p>
<p>Research on past extinctions provides data on how ecosystems change in response to severe climate change. It also shows how species adapt to their new environment. This information can be applied to today’s world, which is currently in the midst of a <a href="http://www.theguardian.com/environment/radical-conservation/2015/oct/20/the-four-horsemen-of-the-sixth-mass-extinction">sixth mass extinction</a>. </p>
<p>We can use information from the past to predict which species might survive and which may be more sensitive to extinction. In this way we can learn how to conserve susceptible species such as those that take many years to reach adulthood. Those that take longer to breed or have few young may be more likely to become extinct than those that breed when they are still young and have many babies.</p><img src="https://counter.theconversation.com/content/60338/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jennifer Botha-Brink receives funding from the National Research Foundation, the DST/NRF Centre of Excellence for Palaeosciences and the Palaeontological Scientific Trust and its Scatterlings of Africa programmes. </span></em></p>How did survivors of the Permo-Triassic Mass Extinction adapt to their new, harsh environment? And why is that knowledge so important for modern species?Jennifer Botha, Specialist Museum Scientist and Head of Department (National Museum, Bloemfontein) and Research Affiliate, University of the Free StateLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/579072016-05-12T21:18:10Z2016-05-12T21:18:10ZHow birds endemic to southern Africa are likely to cope with climate change<figure><img src="https://images.theconversation.com/files/122262/original/image-20160512-16402-1sc1zzs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The orange-breasted sunbird is endemic to South Africa's fynbos.</span> <span class="attribution"><span class="source">Marisa Estivill/Shutterstock</span></span></figcaption></figure><p>Southern Africa is noted for its wealth of biological diversity and for its high proportion of endemic species. These are species that are unique to a specific location and are found nowhere else in the world. Many of the region’s endemic species can be found in South Africa’s fynbos and succulent Karoo <a href="http://www.biology-online.org/dictionary/Biome">biomes</a>. </p>
<p>While it is important to understand how biodiversity arises in particular regions, it is even more important to understand how it is maintained. This is particularly pressing given the <a href="https://www.cbd.int/intro/default.shtml">global commitment</a> to conserving biodiversity and the changes in the global environment. Climatic changes, in particular, lead to changes both in the areas occupied by individual species and in the areas able to support particular biomes.</p>
<p>Given the pace and magnitude of the climatic changes now taking place, it is vital to understand how these will affect our ability to conserve biodiversity.</p>
<p>Our study investigated this by examining how present biodiversity patterns in southern Africa are related to past climatic changes. In particular we studied the extent to which these led to changes in the extent and location of the biomes. </p>
<p>Our results showed that the current diversity of biome-associated endemic species is greatest in areas where the same biome has been able to persist. This result for birds, a relatively mobile group, is almost certainly the same for other less mobile groups. </p>
<p><a href="http://onlinelibrary.wiley.com/doi/10.1111/jbi.12714/full#references">Our study</a>, published in the <em>Journal of Biogeography</em>, set out to address the question of how diversity is maintained. Answering this question is essential if we are to understand how climatic change will affect biodiversity and to develop strategies to meet global biodiversity conservation targets.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/122133/original/image-20160511-18128-dwpeyh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/122133/original/image-20160511-18128-dwpeyh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=636&fit=crop&dpr=1 600w, https://images.theconversation.com/files/122133/original/image-20160511-18128-dwpeyh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=636&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/122133/original/image-20160511-18128-dwpeyh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=636&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/122133/original/image-20160511-18128-dwpeyh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=799&fit=crop&dpr=1 754w, https://images.theconversation.com/files/122133/original/image-20160511-18128-dwpeyh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=799&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/122133/original/image-20160511-18128-dwpeyh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=799&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Southern African biomes.</span>
</figcaption>
</figure>
<h2>Studying diversity</h2>
<p>We tested two hypotheses: that present patterns of diversity and occurrence of endemic species, are related to</p>
<ul>
<li><p>stability of the climate; and/or </p></li>
<li><p>persistence of a biome over glacial-interglacial time scales. </p></li>
</ul>
<p>We tested our hypotheses using as a model group of organisms the 697 native bird species that breed in southern Africa. These included 163 regional endemics, such as the <a href="http://animaliaz-life.com/image.php?pic=/data_images/orange-breasted-sunbird/orange-breasted-sunbird5.jpg">orange-breasted sunbird</a>, endemic to the fynbos, and the <a href="http://www.warwicktarboton.co.za/images/BIRD%20jpgs/resized/235-Karoo-Korhaan-WTa.jpg">Karoo korhaan</a>, endemic to the Karoo. We used bird species because their present distribution in the region is <a href="http://www.adu.org.za/pdf/SABAP1_Introduction.pdf">more completely mapped</a> than other major groups. </p>
<p>We looked at the past 140,000 years. This extends from the penultimate glacial period through the last <a href="http://www.pnas.org/content/104/2/450.abstract">interglacial period</a> (starting about 127,200 years ago), through the <a href="http://www.sciencedirect.com/science/article/pii/S0277379114003485">last glacial period</a> (starting about 109,500 years ago) and the current interglacial or Holocene period (starting about 11,700 years ago). </p>
<p>During glacial periods, large areas of the northern hemisphere continents were covered by <a href="https://commons.wikimedia.org/wiki/File:Iceage_north-intergl_glac_hg.png">ice sheets</a> and the global climate was markedly colder and drier. Climate during the periods between glacials – interglacials – more closely resembled that of the past two centuries. </p>
<p>The glacial-interglacial time scale is significant because the changes in global climate during this period are the largest-magnitude climatic changes of the recent geological past. They are also <a href="http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-chapter6.pdf">comparable</a> with those projected for the near future if greenhouse gases continue to be put into the atmosphere at the <a href="https://www.ipcc.ch/pdf/assessment-report/ar5/wg1/WG1AR5_SPM_FINAL.pdf">present rate</a>.</p>
<p>We used the results from a series of 78 climate model experiments for time slices throughout this period as the <a href="https://www.researchgate.net/publication/229345937_High-latitude_climate_sensitivity_to_ice-sheet_forcing_over_the_last_120kyr">basis for our study</a>.</p>
<h2>Climate variation</h2>
<p>Using the results of the climate model experiments and a <a href="http://www.ipcc-data.org/observ/clim/get_30yr_means.html">global dataset</a> of recent (1961-90) climatic conditions for the cells of a 0.5° longitude x latitude grid, we calculated the climate of each 0.5° grid cell in southern Africa for each of the 78 time slices. We then computed several measures of relative climatic stability over the past 140,000 years for each grid cell. </p>
<p>We predicted the present diversity of native breeding bird species for each grid cell using models relating each species’ <a href="http://www.adu.org.za/pdf/SABAP1_Introduction.pdf">mapped present distribution</a> to <a href="http://www.ipcc-data.org/observ/clim/get_30yr_means.html">recent climate</a>.</p>
<p>We then calculated, for each grid cell, the correlation between the present diversity of birds and the various measures of climatic stability. </p>
<p>Our results showed that overall diversity did not correlate with climatic stability. But they showed that the number of endemic species present in a grid cell today was significantly positively correlated with climatic stability. In other words, the more stable the climate has been, the greater the number of endemic species present today. </p>
<h2>Biome persistence</h2>
<p>To test our second hypothesis we first fitted models describing the relationship between the present extent of each of the nine regional biomes and the <a href="http://www.ipcc-data.org/observ/clim/get_30yr_means.html">present climate</a>. Using these and the 78 climates computed for each grid cell, we then predicted the occurrence and extent of each biome in each grid cell for each time slice. </p>
<p>The degree of persistence of each biome in each grid cell was assessed in three ways. We then calculated correlations between the three measures of biome persistence for each grid cell and the present number of biome-associated endemic bird species found in each grid cell. </p>
<p>We found strong positive correlations between biome persistence and the number of biome-associated endemics found today in grid cells. That is, the greatest numbers of biome-associated endemics are found today where the relevant biome has been able to persist through most or all of the past 140,000 years. </p>
<h2>The threat of extinction</h2>
<p>Overall we found that the diversity of endemic bird species in the region is highest where climate has varied least over the past 140,000 years, and especially where the degree of variation of climate has been sufficiently small to enable the same biome to persist.</p>
<p>This result has important implications for the conservation of regional avian diversity as well as global biodiversity. This is because it shows that climatic changes lead to changes in biomes that, in turn, affect the survival of species using those biomes. </p>
<p>It is projected that the climatic changes being caused by current levels of greenhouse gas emissions will be sufficiently large by 2100 to lead to an eventual <a href="http://www.pnas.org/content/104/14/5738.abstract">change of biome</a> across more than half the earth’s land surface. In the case of species that are endemic to an area and use a particular biome, like the birds we studied, this may result in their extinction. </p>
<p>Avoiding such a catastrophe requires countries to implement measures, as <a href="http://www.cop21.gouv.fr/en/more-details-about-the-agreement/">agreed in Paris</a>, to limit future climatic change. It also needs conservation strategies that, for example, include management of the wider landscape to facilitate species’ range shifts and the maintenance of species’ habitats. This will facilitate their adaptation to levels of climatic change already under way.</p><img src="https://counter.theconversation.com/content/57907/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Brian Huntley currently receives funding from the UK Natural Environment Research Council and the Leverhulme Trust to support his research. He is a member of the IUCN SSC Climate Change Specialist Group and a consultant to the Council of Europe Bern Convention Group of Experts on Biodiversity and Climate Change.</span></em></p>Given the global commitment to conserve biodiversity in the face of climate change, it is important to understand how biodiversity arises in the first place – and how it is maintained.Brian Huntley, Professor of Biological and Biomedical Sciences, Durham UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/502122015-11-06T04:23:15Z2015-11-06T04:23:15ZHow climate change is causing pied crow numbers to soar<figure><img src="https://images.theconversation.com/files/100923/original/image-20151105-16273-xh91ux.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Pied crow numbers are growing because of powerlines and climate change. This growth is distressing to some.</span> <span class="attribution"><span class="source">Peter Ryan</span></span></figcaption></figure><p>Pied crows, or <a href="http://www.oiseaux-birds.com/card-pied-crow.html">Corvus albus</a>, are a natural part of the landscape of southern Africa. They are bold, common, and familiar. But over recent years, especially in South Africa, there is evidence that there are <a href="http://onlinelibrary.wiley.com/doi/10.1111/ddi.12381/full">many more</a> of these birds.</p>
<p>The increase is worrying some <a href="http://karoospace.co.za/the-problem-with-pied-crows/">conservationists</a> who fear it could be having a negative impact on the local biodiversity. These fears have some merit given that the species is known to predate on birds’ nests and <a href="http://oo.adu.org.za/pdf/OO_2014_05_135-138.pdf">young tortoises</a>. Farmers are also concerned about the potential damage to <a href="http://groundup.org.za/article/where-lambs-have-no-eyes_3002">sheep flocks</a> because crows pluck out the eyes of the young lambs.</p>
<h2>The effect of changes in temperature</h2>
<p>Our <a href="http://onlinelibrary.wiley.com/doi/10.1111/ddi.12381/abstract">research</a> confirms that there has been an increase in pied crows in South Africa and quite dramatic changes in their centre of abundance. These changes vary throughout the country with large increases in the southwest but declines in the north and east of the country.</p>
<p>Second, our results suggest that these changes are closely linked to climate change.</p>
<p>Using data from two <a href="http://sabap2.adu.org.za/">bird atlases</a> carried out 20 years apart and linking these changes with information on the changing climate, we found that pied crows have increased mainly in the geographic areas of South Africa known as the <a href="http://www.southafrica.net/za/en/articles/entry/article-southafrica.net-the-magical-great-karoo">Karoo</a> and Fynbos shrublands which are distinctive types of vegetation of southwestern South Africa. This is where temperatures are warming. These biomes are relatively arid habitats consisting principally of short shrubs with very few natural trees.</p>
<p>The decline in numbers in the northwest of the country is most likely related to climate cooling in this region.</p>
<p>It appears that the crows are following a warming climate bubble into the southwest. <a href="http://onlinelibrary.wiley.com/doi/10.1111/ddi.12381/abstract">Our research</a> suggests pied crows have a preferred temperature range roughly equal to an average annual temperature of 19°C. We are approaching this in the southwest of South Africa at the moment, and the crows are loving it.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/100924/original/image-20151105-16273-wcep3x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/100924/original/image-20151105-16273-wcep3x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/100924/original/image-20151105-16273-wcep3x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=461&fit=crop&dpr=1 600w, https://images.theconversation.com/files/100924/original/image-20151105-16273-wcep3x.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=461&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/100924/original/image-20151105-16273-wcep3x.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=461&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/100924/original/image-20151105-16273-wcep3x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=579&fit=crop&dpr=1 754w, https://images.theconversation.com/files/100924/original/image-20151105-16273-wcep3x.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=579&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/100924/original/image-20151105-16273-wcep3x.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=579&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">South Africa’s pied crows are moving to areas where the climate favours them more.</span>
<span class="attribution"><span class="source">Peter Ryan</span></span>
</figcaption>
</figure>
<p>Our results also suggest that this shift has been aided by the presence of power line infrastructure. This has provided sites for crows to build their nests in what is otherwise a virtually treeless landscape. </p>
<p>We conclude that while power lines have facilitated the increase of pied crows in the Karoo, climate change has driven their soaring numbers in these areas. The combination of climate change and electrical infrastructure has created the “perfect storm” of conditions to favour an explosion of pied crow numbers in the shrublands of South Africa.</p>
<h2>An unloved species</h2>
<p>Crows are big and obvious. Pied crows in particular are easy to identify with their white tank top plumage. These birds have had a bad rap globally. This dates back to medieval times when they were reviled as carrion birds on battlefields, or to superstitious associations of large, black birds with ill-omen or <a href="http://www.perspectivesmagazine.sk/news/ravens-and-crows-in-mythology-folklore-and-religion/">death</a>. </p>
<p>Their collective noun – a <a href="http://crow.bz/main/murder.htm">murder of crows</a> – doesn’t exactly do much for their public image. Given all this history, it is perhaps understandable that people react emotionally when they see crows doing what crows do best: being predators. </p>
<p>In South Africa pied crows are notorious, and viewed with great suspicion by urbanites and rural farmers alike. They are accused of such gory deeds as plucking the eyes from new born <a href="http://groundup.org.za/article/where-lambs-have-no-eyes_3002">lambs</a>, destroying the eggs of ground-nesting birds and decimating populations of <a href="http://oo.adu.org.za/pdf/OO_2014_05_135-138.pdf">tortoises</a>. </p>
<p>They’re also vilified for harassing other much more glamorous species, notably <a href="http://www.fitzpatrick.uct.ac.za/sites/default/files/image_tool/images/275/Publications/PDF_Archive/Africa_Birds_And_Birding/Author_Index/ABB16%285%2950-54.pdf">Verraux’s eagles</a>. Indeed these perceptions have led to calls for the control of pied crows by those who are worried about their negative impacts.</p>
<p>But these observations are not sufficient evidence to suggest that crows have an overwhelming negative impact on ecosystems. A recent scientific <a href="http://onlinelibrary.wiley.com/doi/10.1111/ibi.12223/abstract">review</a> suggests that in general, they don’t.</p>
<p>The truth is that their role within ecosystems is not necessarily so straight forward. For example, they also eat other predators, such as small snakes which can be a major cause of nest failure in <a href="http://www.umt.edu/mcwru/personnel/martin/PDF%20Martin/Influence%20of%20nestsite%20characteristics2004.pdf">Karoo birds</a>. Thus, increased numbers of pied crows certainly have the potential to change the balance of predator-prey interactions.</p>
<p>Given the situation, it may be that pied crows are an example of the relatively new phenomenon of the <a href="http://conservationbytes.com/2012/09/07/native-invaders-divide-loyalties/">native invader</a>. These are species that occur naturally in one area, but whose numbers suddenly increase out of all proportion with their surrounding ecosystems, shifting the balance of <a href="http://www.esajournals.org/doi/abs/10.1890/110060">nature</a> in unpredictable ways.</p>
<p>For a species to be considered a native invader in the truest sense it needs demonstrably to have a negative impact on other species. But while the pied crow clearly has such potential, we do not yet have the evidence to confirm they are causing declines of other species. Therefore, in assessing the pied crow “problem” we must be careful not to jump to <a href="http://www.westerncapebirding.co.za/conservation/368/blsa_position_statement_on_pied_crows">conclusions</a>. </p>
<h2>Climate change is ongoing</h2>
<p>Throughout the world, animals and plants are responding to the changing climate by shifting their ranges, changing their behaviour and changing their <a href="http://gyohe.faculty.wesleyan.edu/files/2010/11/Parmesan-Yohe-Nature.pdf">abundance</a>.</p>
<p>But climate change is ongoing, and so these shifts may continue to change over time. It is likely that we are not stepping into a new stable state but rather witnessing one step in a continual transition as species adjust or fail to adjust to conditions that are in a state of flux.</p>
<p>What happens next is uncertain. </p>
<p>As warming continues, will pied crow numbers in the south west of South Africa again subside? Or will they adapt to their new conditions? Either way, it is still unclear what the legacy of the “pied crow invasion” will be.</p><img src="https://counter.theconversation.com/content/50212/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Susan Cunningham receives funding from the DST-NRF Centre of Excellence at the Percy FitzPatrick Institute, University of Cape Town. </span></em></p><p class="fine-print"><em><span>Arjun Amar receives funding from the DST-NRF Centre of Excellence at the Percy FitzPatrick Institute, University of Cape Town. </span></em></p>South Africa’s pied crows are moving to areas where the climate suits them more.Susan Cunningham, Lecturer, Percy FitzPatrick Institute, University of Cape TownArjun Amar, Senior Lecturer, Percy FitzPatrick Institute of African Ornithology, University of Cape TownLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/431232015-07-16T04:27:56Z2015-07-16T04:27:56ZUnpacking the secrets of South Africa’s dolerite sills<figure><img src="https://images.theconversation.com/files/88219/original/image-20150713-11831-cm68jl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Dolerite sills so distinctive of the Karoo scenery in South Africa</span> <span class="attribution"><span class="source">Grant Cawthorn</span></span></figcaption></figure><p>The exploitation of mineral deposits always creates debates around economic necessity versus environmental preservation. Fracking for gas in the <a href="http://www.southafrica.net/za/en/articles/entry/article-southafrica.net-the-magical-great-karoo">Karoo</a> region of South Africa is currently vigorously debated. This article is not about fracking, but it does touch on aspects of gas retention or loss in the Karoo rocks. It also highlights the potential for other mineral deposits in the same area.</p>
<h2>Formation of rocks in the Karoo</h2>
<p>The <a href="http://www.zulu.org.za/discover/destinations/drakensberg">Drakensberg</a> dominate the mountainous country of Lesotho in southern Africa, and are composed entirely of <a href="http://volcano.oregonstate.edu/book/export/html/170">basaltic lavas</a> (like Hawaii). </p>
<p>The eruption of these lavas ended a protracted period of accumulation of sedimentary material from 300 to 180 million years ago – sand (now yellow sandstone), clay (now blue-black shale) and organic material, the latter producing South Africa’s extensive coal deposits, no oil, but possibly gas accumulations.</p>
<p>The total thicknesses of these sedimentary layers and lava flows probably reached 6 km and 2 km respectively. These sedimentary layers and lavas covered much of <a href="http://www.livescience.com/37285-gondwana.html">Gondwana</a>, the ancient mega-continent of Africa, South America, India, Australia and Antarctica that split and drifted apart due to the forces of volcanic eruptions 180 million years ago. </p>
<h2>Dolerite sills</h2>
<p>Associated with the vast outpouring of lava there was a huge deep plumbing system of molten rock, called <a href="http://education.nationalgeographic.com/education/encyclopedia/magma/?ar_a=1">magma</a>. Magmas originated by melting at depths of 100 km inside the Earth, and infiltrated their way upward to surface. Any joints, cracks or weaknesses in the Earth’s crust would have been exploited by invading magma. The sedimentary rocks are like piles of pancakes – very thin layers with definite parting surfaces in between. </p>
<p>The magma invading upward injected horizontally along these parting surfaces, for tens to even a hundred km. As the magma cooled it produced a hard, black rock (not unlike the basalt lavas) that is called <a href="http://www.geographyinaction.co.uk/Geology%20files/Dolerite.html">dolerite</a>. Where the magma invaded a horizontal bedding plane we call it a sill. </p>
<p>Being much harder than the under- and over-lying sandstones and shales, these dolerite sills form the flat-topped hills so distinctive of the Karoo scenery in South Africa. <a href="http://link.springer.com/chapter/10.1007/11157_2014_7">Studies</a> have shown that the Karoo succession contains about 10% of its thickness as dolerite sills with an average individual sill thickness of 30m. Where the magma solidified in a steep fracture we call it a dyke.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/85877/original/image-20150622-17729-1ukflw6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/85877/original/image-20150622-17729-1ukflw6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/85877/original/image-20150622-17729-1ukflw6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/85877/original/image-20150622-17729-1ukflw6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/85877/original/image-20150622-17729-1ukflw6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/85877/original/image-20150622-17729-1ukflw6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/85877/original/image-20150622-17729-1ukflw6.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">Dolerite dyke cutting across layers of sedimentary rocks.</span>
<span class="attribution"><span class="source">Grant Cawthorn</span></span>
</figcaption>
</figure>
<h2>Trapping of gas in the rocks</h2>
<p>Two very different potentially economically important aspects of these sills are worthy of explanation. The first relates to gas preservation. Many analogies have been drawn between the gas-bearing shales in sedimentary formations around the world with the Karoo rocks in South Africa and the well-known issues about economics versus environment are vigorously debated.</p>
<p>However, the Karoo is the only example that has abundant dolerite sills. There are two potentially opposing effects of the dolerite sills. Gas formed from decomposing organic plant material that was buried under thick layers of sand and clay. Gas would normally leak upward very slowly through small pores and spaces in the rocks until it was trapped beneath a layer of rock that has no pores. We call that layer impermeable. </p>
<p>The dolerite sills form such impermeable layers and so may have acted as good trap rocks for the gas. Thus the rocks beneath a dolerite sill might provide a good exploration <a href="http://karoospace.co.za/dolerite-karoos-fracking-game-changer/">target</a>. </p>
<p>But there is also an opposing process. The magma intruded at 1200 degrees Celsius. As it cooled it heated the surrounding rocks. The width of this heating zone depended on the thickness of the dolerite sill. The highest temperature at which gas can survive is about 250 degrees Celsius, above that temperature it will be burnt. That temperature will be exceeded for all the surrounding rocks that are within half the thickness of the dolerite itself (both above and below).</p>
<p>Any gas present in the sedimentary rocks at 180 million years ago within that distance of the sill would have been destroyed. Thus, a 30m-thick sill would burn all the gas within 15m above and below. At a number of surface localities the sedimentary rocks have been found to display a very unusual structure. </p>
<p>The rocks have been broken and re-cemented, and extensively altered. These features have been attributed to the release of high temperature fluids and gases from depth. Are they evidence that the intrusion of the dolerites liberated gases that streamed upward? If so, there may be less gas than anticipated. So we do not know what to expect the effect of the dolerite might be in terms of gas preservation. </p>
<h2>Hidden nickel and copper deposits</h2>
<p>The second potential economic aspect relates to nickel-copper sulphide mineralisation. A considerable proportion of the World’s nickel is mined from dolerites. The best example is in Siberia, Russia. In South Africa there was one small mine for nickel-copper sulphide mineralisation at <a href="http://travelingluck.com/Africa/South+Africa/Eastern+Cape/_994651_Insizwa+Mine.html">Insizwa</a>, near <a href="http://www.southafrica.com/blog/explore-historic-kokstad">Kokstad</a>, in KwaZulu-Natal. The intrusion is 1000m thick.</p>
<p>Although negligible amounts of ore were ever mined, there is chemical evidence that much larger deposits ought to occur at its base. The logic is that if an immiscible sulphur-rich liquid separated from the magma (like oil separating from water, or grease droplets forming on a cooling bowl of washing-up water) a considerable proportion of the nickel and copper would be extracted into the sulphide liquid, which then forms an ore deposit. </p>
<p>The remaining magma would then be depleted in nickel and copper compared to its original composition. Based on the difference between “normal” basalt and the Insizwa rocks it is possible to calculate that enormous masses of nickel-copper-rich sulphide ought to be hidden below the intrusion. </p>
<p>I know of four other dolerite intrusions in the Karoo that have this characteristic nickel-copper depletion with the implication that they too could host valuable metal resources at their bases. Would their exploration and beneficiation create national opposition analogous to that generated around fracking?</p><img src="https://counter.theconversation.com/content/43123/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Grant Cawthorn received funding from AngloPlatinum, Lonplats, Impala Platinum and the National Research Foundation, South Africa.</span></em></p>South Africa’s Karoo area has potential for gas deposits and other mineral deposits like nickel and copper.Grant Cawthorn, Professor of Geochemistry and Petrology, University of the WitwatersrandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/439262015-07-15T04:34:33Z2015-07-15T04:34:33ZAncient plant eating cousins from Brazil and South Africa are reunited<figure><img src="https://images.theconversation.com/files/87382/original/image-20150704-20468-dfudj7.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Artistic reconstruction of two Tiarajudens males during combat in the Permian of southern Brazil.</span> <span class="attribution"><span class="source">Supplied</span></span></figcaption></figure><p>New <a href="http://rsos.royalsocietypublishing.org/">evidence</a> has been provided confirming previous <a href="http://www.nature.com/news/earth-science-how-plate-tectonics-clicked-1.13655">compelling</a> geological findings that today’s continents were once linked in one giant land mass. The evidence has come through the discovery that two fossils, one from South Africa and the other from Brazil, were cousins.</p>
<p>The discovery of a Brazilian plant-eating herbivore fossil in 2008 prompted a restudy of the South African cousin of the same size and with a remarkably similar skull discovered 10 years earlier. These two species from <a href="http://www.livescience.com/37285-gondwana.html">Gondwana</a> – the ancient super continent formed by now separated southern continents such as Africa and South America – show features in their skull and teeth that indicate they were closely related.</p>
<p>Close examination of the two skulls, identified as four-legged or tetrapod animals that date back to a time before dinosaurs existed, revealed two further astonishing facts. The first is that 270 million years ago they were already capable of chewing their food like modern ruminants such as cattle, sheep, goats and deer. </p>
<p>The fossils, which date from what is known as the Middle Permian period, also show that the plant-eating tetrapods had developed two specialisations that they used in combat – a feature typical of today’s cows and deer.</p>
<p>And the most fascinating aspect of all is that these not too distant cousins were found more than 8000 kilometres apart on different modern day continents.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/87380/original/image-20150704-20484-1hc0qj2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/87380/original/image-20150704-20484-1hc0qj2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=297&fit=crop&dpr=1 600w, https://images.theconversation.com/files/87380/original/image-20150704-20484-1hc0qj2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=297&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/87380/original/image-20150704-20484-1hc0qj2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=297&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/87380/original/image-20150704-20484-1hc0qj2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=373&fit=crop&dpr=1 754w, https://images.theconversation.com/files/87380/original/image-20150704-20484-1hc0qj2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=373&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/87380/original/image-20150704-20484-1hc0qj2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=373&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The skulls of Anomocephalus africanus (left) and Tiarajudens eccentricus (right).</span>
<span class="attribution"><span class="source">Supplied.</span></span>
</figcaption>
</figure>
<h2>The deers of yesteryear</h2>
<p>Living mammals have a rich history documented by fossils going back 300 million years. Ancestral lineages of mammals were included in a group known as <a href="http://global.britannica.com/animal/therapsid">therapsids</a> that flourished during the <a href="http://www.ucmp.berkeley.edu/permian/permian.php">Permian</a>, which predated the age of dinosaurs, and are exquisitely documented in the Karoo Basin of South Africa.</p>
<p>Plant-eating animals are now far more diverse and abundant than carnivores, a trend that began during the Permian. A particular group called anomodonts can best be described as the “Permian deers”. Besides being plant-eating and the most abundant lineage of the Permian, anomodonts were extremely variable in size. They were also very different in their shapes, particularly the earliest members of the group.</p>
<p>The Brazilian fossil had some unexpected features for a herbivore. Three stand out. The first is that it had occluding teeth that allowed them to chew, or masticate, food – a feature that is a landmark of today’s mammals.</p>
<p>The second is that it had a long outsized blade-like canine (~120 mm long). This shows, for the first time, the presence of saber-tooth in herbivores mammals around 270 million years ago. Saber teeth are found in some great carnivores from the past such as the <a href="http://www.ucmp.berkeley.edu/synapsids/gorgonopsia.html">gorgonopsians</a> or the <a href="http://www.enchantedlearning.com/subjects/mammals/smilodon/"><em>Smilodon</em></a> sabre-toothed cat, and other Ice Age cats.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/87381/original/image-20150704-20453-1ay1nxr.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/87381/original/image-20150704-20453-1ay1nxr.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=422&fit=crop&dpr=1 600w, https://images.theconversation.com/files/87381/original/image-20150704-20453-1ay1nxr.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=422&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/87381/original/image-20150704-20453-1ay1nxr.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=422&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/87381/original/image-20150704-20453-1ay1nxr.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=531&fit=crop&dpr=1 754w, https://images.theconversation.com/files/87381/original/image-20150704-20453-1ay1nxr.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=531&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/87381/original/image-20150704-20453-1ay1nxr.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=531&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The skull of the Asian water-deer Hydropotes inermis.</span>
<span class="attribution"><span class="source">Provided.</span></span>
</figcaption>
</figure>
<p>But carnivores do not need to chew their food, so that the Brazilian anomodont had several occluding teeth proved that it was a dedicated herbivore after all.</p>
<p>But the surprises did not end there. <em>Tiarajudens eccentricus</em>, the Brazilian species, show teeth that are commonly located at the margin of the mouth, positioned on a bone of the palate. The novelty is that no other therapsid was known to possess teeth in this bone. In fact no other therapsids are known to have complex, molar-like teeth (molariforms) in the roof of their mouths.</p>
<p>After additional cleaning of the bones of the fossil found in South Africa, called <a href="http://rspb.royalsocietypublishing.org/content/266/1417/331.short"><em>Anomocephalus africanus</em></a>, it was found it also had molariforms in the palate, identical to those of <em>Tiarajudens</em>. The South African fossil has a complete mandible and its teeth are in contact with the palate, confirming the occlusion between upper and lower teeth. The only apparent difference between the two fossils is the absence of blade-like canines in the African species.</p>
<p>The skull of these cousins are nearly the same size – between 210 and 220 mm. They show a domed profile with a very short snout, large orbits, and temporal opening for chewing muscles about the same size or slightly larger than the eye socket.</p>
<p>The long canine in the Brazilian species is represented in a few living deer such as the Asian water-deer, musk-deer, and muntjacs. In all these cases the enlarged canines are used in male-male visual displays during fighting. The long canine in <em>Tiarajudens eccentricus</em> is being interpreted as an indication of its use in a similar way, representing the oldest evidence of use of canine in a herbivore for male-male fight.</p><img src="https://counter.theconversation.com/content/43926/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Fernando Abdala receives funding from the National Research Foundation of South Africa.</span></em></p><p class="fine-print"><em><span>Juan Carlos Cisneros receives funding from Conselho Nacional de Desenvolvimento Científico e Tecnológico of Brazil.</span></em></p>New evidence shows marked similarities between two fossils – one from Brazil, the other South Africa. This confirms compelling geological findings that continents were once one giant land mass.Fernando Abdala, Reader, Evolutionary Studies Institute, University of the WitwatersrandJuan Carlos Cisneros, Lecturer in Palaeontology, Universidade Federal do Piauí (UFPI)Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/430452015-06-15T04:04:17Z2015-06-15T04:04:17ZWhy South Africa’s Karoo is a palaeontological wonderland<figure><img src="https://images.theconversation.com/files/84466/original/image-20150609-10701-f71o0r.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Spectacular landscape of the Nuweveld escarpment showing exposures of the Beaufort Group. </span> <span class="attribution"><span class="source">SUPPLIED</span></span></figcaption></figure><p>South Africa’s Karoo region has been in the headlines in recent years because of the prospect of a controversial fracking programme to exploit its potential shale gas resources. But, to palaeontologists, the Karoo Supergroup’s rocks hold the key to understanding the early evolutionary history of the major groups of land vertebrates – including tortoises, mammals and dinosaurs. </p>
<p>More than 200 million years ago, South Africa formed part of the southern hinterland of Pangaea, the great single supercontinent, which was inhabited by a diverse flora and fauna. </p>
<p>In only a few places, where conditions were conducive to their fossilisation, can palaeontologists catch a glimpse of these ancient ecosystems. The Karoo is one such place.</p>
<h2>Why it’s such a special place</h2>
<p>About 265 million years ago, the Beaufort Group of rocks within the Karoo sequence was beginning to be deposited by rivers draining into the shrinking inland Ecca Sea. As these rivers filled the basin with sediment they entombed the remains of land animals that lived around them. The youngest Beaufort rocks are around 240 million years old.</p>
<p>Today, more than 30,000 fossils of vertebrate animals from the Beaufort reside in museum collections across the world. The Beaufort was followed by the Molteno and Elliot formations. The Elliot formation is made up of a succession of red rocks that records some of the earliest dinosaur communities.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/84824/original/image-20150612-1456-8sdtqb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/84824/original/image-20150612-1456-8sdtqb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/84824/original/image-20150612-1456-8sdtqb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=397&fit=crop&dpr=1 600w, https://images.theconversation.com/files/84824/original/image-20150612-1456-8sdtqb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=397&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/84824/original/image-20150612-1456-8sdtqb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=397&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/84824/original/image-20150612-1456-8sdtqb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=499&fit=crop&dpr=1 754w, https://images.theconversation.com/files/84824/original/image-20150612-1456-8sdtqb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=499&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/84824/original/image-20150612-1456-8sdtqb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=499&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Map showing the formations of the Karoo Supergroup.</span>
<span class="attribution"><span class="source">Supplied</span></span>
</figcaption>
</figure>
<p>The area plays a crucial role in revealing the distant origin of mammals, tortoises and dinosaurs. It also covers two great extinction events, the end-Permian (252 million years ago) and the end-Triassic (200 million years ago). </p>
<p>Because of its continuity of deposition, the Karoo provides not only a historical record of biological change over this period of Earth’s history, but also a means to test theories of evolutionary processes over long periods of time.</p>
<p>The 400,000 sq km area is internationally noted for its record of fossil therapsid “mammal-like” reptiles. These chart anatomical changes on the path to mammals from their early tetrapod forebears. </p>
<p>The Beaufort Group has also yielded the oldest recorded fossil ancestor of living turtles and tortoises – the small, lizard-like <a href="http://www.nature.com/ncomms/2014/141107/ncomms6211/full/ncomms6211.html?WT.ec_id=NCOMMS-20141111">Eunotosaurus</a>. The younger Elliot Formation preserves a record of early dinosaurs that could help palaeontologists understand the rise of the giant sauropod dinosaurs of the Jurassic Period. </p>
<h2>Physiology and behaviour</h2>
<p>Many studies are still being done on the identification of new species from the Karoo. But a lot of current research is also focused on the relationship between the extinct animals and their environments. </p>
<p>The story of the therapsid’s burrow is a good example of how insights are being gained on the behaviour of prehistoric animals. Roger Smith was the first palaeontologist to <a href="http://www.researchgate.net/publication/236982089_Helical_burrow_casts_of_therapsid_origin_from_the_Beaufort_Group_(Permian)_of_South_Africa">recognise</a> <a href="http://en.wikipedia.org/wiki/Therapsida">therapsid</a> vertebrate burrows in the Karoo. He described helical burrows, which he attributed to a small species of dicynodont (two-dog tooth) therapsid called Diictodon. In the fossil record, burrows are preserved not as hollows, but as the plug of sediment that filled them. </p>
<p>X-ray tomography at a facility in France was recently used <a href="http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0064978">to scan</a> one of these burrows. This showed that it was home not only to its maker – the meerkat-sized therapsid Thrinaxodon – but also to the early amphibian Broomistega. Further research revealed that the Thrinaxodon was probably hibernating and this is the reason why it tolerated the intruding amphibian which was using the burrow to convalesce while suffering from broken ribs. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/84873/original/image-20150612-1481-l98cd7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/84873/original/image-20150612-1481-l98cd7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=364&fit=crop&dpr=1 600w, https://images.theconversation.com/files/84873/original/image-20150612-1481-l98cd7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=364&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/84873/original/image-20150612-1481-l98cd7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=364&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/84873/original/image-20150612-1481-l98cd7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=457&fit=crop&dpr=1 754w, https://images.theconversation.com/files/84873/original/image-20150612-1481-l98cd7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=457&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/84873/original/image-20150612-1481-l98cd7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=457&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Partners forever, the amphibian <em>Broomistega</em> and mammal fore-runner Thrinaxodon preserved in a fossil burrow.</span>
<span class="attribution"><span class="source">Supplied</span></span>
</figcaption>
</figure>
<p>Studying how fossil bones are preserved (taphonomy) can provide similarly rich insights. For example, it has been <a href="http://www.sciencedirect.com/science/article/pii/S0031018213003787">suggested</a> that changes in preservation style between skeletons in the latest Permian Period (about 253 million years ago) to those in the earliest Triassic Period (about 252 million years ago) can be attributed to changes in climate. The region developed from being seasonally dry floodplains with high water tables to predominantly dry floodplains. </p>
<p>Because of the abundance of fossil tetrapods in the rocks of the Karoo Supergroup, they have been used to divide the rock succession into fossil zones, called biozones. This has enabled the biozones to be correlated with equivalent sequences elsewhere in the world and forms the basis of reconstructing global patterns of diversity. </p>
<p>Understanding the sequence of events is crucial for testing hypotheses of evolutionary processes. It is an area of research being pursued for both the Permian and Triassic periods.</p>
<h2>The big wipe-outs</h2>
<p>The end-Permian mass extinction, the greatest, was responsible for the elimination of 90% of species living in the sea and 70% of species living on land. Roger Smith’s <a href="http://www.sciencedirect.com/science/article/pii/S0031018214000030">work</a> on Karoo fossil vertebrates shows this extinction to have lasted approximately 300,000 years, terminating at the Permian-Triassic boundary 252 million years ago. It was followed by a lesser extinction pulse approximately 160,000 years later in the Early Triassic.</p>
<p>Our current work is focusing on the more obscure Guadalupian extinction which occurred eight million to ten million years before the end-Permian. This is recognised from marine sequences. For the first, time empirical evidence for this event on land is being discovered from the Karoo fossil record. </p>
<h2>What’s next?</h2>
<p>These are exciting times for palaeontologists. Technological and scientific developments have opened up new vistas for their work.</p>
<p>A comprehensive database of all the Karoo fossil vertebrate collections in South Africa has been built. This is the first database of Permian-Jurassic continental vertebrates. It is available to scientists globally, an invaluable tool for biogeographic and biostratigraphic studies. </p>
<p>Better dating techniques are opening up the possibility of working out rates of evolution in fossil tetrapod lineages. High-resolution scanning techniques are also enabling palaeoscientists to explore areas which were previously inaccessible, or at least not without damaging the fossils. </p>
<p>There are a myriad questions that remain unanswered. Were the early mammal ancestors of the Karoo warm-blooded? What can the Karoo tell us about the reaction of terrestrial ecosystems to mass extinction events? How can the Karoo’s shifting ecological make-up shine a light on evolutionary tempo? These are questions we can now attempt to answer.</p><img src="https://counter.theconversation.com/content/43045/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Bruce Rubidge works for the Evolutionary Studies Institute, University of the Witwatersrand. He receives funding from the NRF/DST Centre of Excellence in Palaeosciences, the Palaeontological Scientific Trust (PAST) and the NRF.</span></em></p><p class="fine-print"><em><span>Mike Day works for the Evolutionary Studies Institute, University of the Witwatersrand. He receives funding from the NRF/DST Centre of Excellence in Palaeontology and the Palaeontologcial Scientific Trust (PAST).</span></em></p>The Karoo provides not only a historical record of biological change over a period of Earth’s history but also a means to test theories of evolutionary processes over long periods of time.Bruce Rubidge, Director, Centre of Excellence in Palaeosciences, University of the WitwatersrandMike Day, Postdoctoral Fellow at Organisational Unit:Evolutionary Studies Institute, University of the WitwatersrandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/422712015-06-09T04:18:16Z2015-06-09T04:18:16ZWhy South Africa needs to pursue the potential of gas from fracking<figure><img src="https://images.theconversation.com/files/84218/original/image-20150608-8719-1h1ejyu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">South Africa could see wells like this if the government gives the go-ahead for fracking to take place. </span> <span class="attribution"><span class="source">shutterstock</span></span></figcaption></figure><p>Fracking has altered the global geopolitics of energy – probably for the better. North America is <a href="http://www.politico.com/magazine/story/2013/11/congratulations-america-youre-almost-energy-independent-now-what-98985.html#.VW1keM-qqko">nearly independent</a> of imported oil and is starting to export gas. It is therefore no surprise that the costs, benefits and risks are being hotly debated in South Africa.</p>
<p>Less than five years ago there was talk that the US had hit peak oil. This meant that it would soon be so beholden to the Middle East for oil that the US dollar would plummet in value because the US balance of trade would be so adverse.</p>
<p>As a consequence of oil and gas production from fracking, the US now has almost enough oil to be fully fuel independent. Other local energy supplies, such as coal, have also been replaced. There are a <a href="http://www.eia.gov/todayinenergy/detail.cfm?id=15491">number of examples</a> in the US where this has happened. About 60GW of coal-fired generation will be closed by 2020. </p>
<p>But the process of fracturing rock by hydraulic pressure to uncover oil or gas <a href="http://www.theguardian.com/environment/2013/dec/14/fracking-hell-live-next-shale-gas-well-texas-us">carries risks</a>. There are many fears about what could go wrong in <a href="http://www.what-is-fracking.com/">fracking</a>. Because of its high-pressure operations, the biggest fears relate to leaks and the consequences of leaks.</p>
<p>Does fracking present a potential solution to South Africa’s energy crisis? Or are the risks too high?</p>
<p>About 75% of South Africa’s energy supply comes from coal. This is very high and only a few countries in the world are this heavily <a href="http://www.bp.com/content/dam/bp/pdf/Energy-economics/statistical-review-2014/BP-statistical-review-of-world-energy-2014-full-report.pdf">dependent on coal</a>. At present 94% of South Africa’s energy needs come from coal and oil. One-fifth of the country’s energy needs are met by oil. And gas makes up less than 1% of its needs. Renewable energy is starting to make a contribution, with the Department of Energy focusing on <a href="http://www.energy.gov.za/files/renewables_frame.html">biomass, wind and solar energy</a>.</p>
<h2>Potential problems and some answers</h2>
<p>In North America more than one million holes have been hydraulically stimulated, the technical term for fracking. There is only <a href="http://www.pnas.org/content/111/39/14076.full">one documented case</a> of a leak of fracking fluids. This happened when the drillers tried to pressurise a hole unaware of the existence of another hole close-by. They spotted their own fluid coming up from the ground and immediately stopped operations. The leak had minimal impact. </p>
<p><a href="http://www.businessdictionary.com/definition/fugitive-emission.html">Fugitive emissions</a> from fracking operations are also a cause for concern because they could contribute to global warming. Methane has <a href="http://www.epa.gov/climatechange/ghgemissions/usinventoryreport.html">25 times greater</a> greenhouse effect than carbon dioxide.</p>
<p>But evidence shows that there is <a href="http://www.ipcc-nggip.iges.or.jp/tsu/intern_report/TSU_InternshipReportRyan.pdf">less than 1%</a> of the production of gas from fracking in the US. The impact is considered to be small. In the US about 100 times the quantity of gas is <a href="http://whatsyourimpact.org/greenhouse-gases/methane-sources">lost naturally</a> from wetlands.</p>
<p>There is also the problem of what to do with the <a href="http://www.waterworld.com/articles/wwi/print/volume-28/issue-5/regional-spotlight-us-caribbean/fracking-wastewater-management.html">water</a> that is ejected when the gas or oil starts to flow. It contains chemicals, sand and mud from the drilling. In the US waste water is being treated using <a href="http://www.waterworld.com/articles/wwi/print/volume-28/issue-5/regional-spotlight-us-caribbean/fracking-wastewater-management.html">normal water purification techniques</a>. It can be treated by normal water purification techniques, and cheaply restored to agricultural level. However, producing drinkable water is more expensive. </p>
<p>There are also fears about the toxicity of the chemicals used in fracking. These arose because at the outset of the industry the composition of the additives was a closely held secret. However, additives are now the subject of commercial supply and sellers <a href="https://fracfocus.org/chemical-use/what-chemicals-are-used">disclose the composition</a>. Recently, the US Environmental Protection Agency has passed legislation requiring <a href="http://www2.epa.gov/hydraulicfracturing">full disclosure</a>. </p>
<p>Fracking does cause environmental damage. The Environmental Protection Agency has recently <a href="http://www2.epa.gov/hfstudy/hydraulic-fracturing-water-cycle">released a report</a> on fracking and its impact on water. It is open for public comment and peer-review. There have been <a href="http://www.dailykos.com/story/2013/11/18/1256454/-Water-board-fines-oil-company-60-000-for-discharging-fracking-fluid">illegal discharges</a> into streams and municipal sewerage works. But most has been the result of <a href="http://energyblog.nationalgeographic.com/2013/10/04/fracking-water-its-just-so-hard-to-clean/">poor handling</a> of water expelled from the well. </p>
<p>In North America a lot of fracking has been done by small companies, known as wildcatters, that engage in speculative drilling. They are <a href="http://ecowatch.com/2014/08/07/jail-for-boss-dump-fracking-waste-ohio-river/">reluctant to spend much</a> on cleaning up the water. Gas majors, such as Shell and BP, are very concerned about their reputation and have, in general, been much more responsible in their handling of the waste water. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/84213/original/image-20150608-8692-1sfsbfg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/84213/original/image-20150608-8692-1sfsbfg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/84213/original/image-20150608-8692-1sfsbfg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=490&fit=crop&dpr=1 600w, https://images.theconversation.com/files/84213/original/image-20150608-8692-1sfsbfg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=490&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/84213/original/image-20150608-8692-1sfsbfg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=490&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/84213/original/image-20150608-8692-1sfsbfg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=615&fit=crop&dpr=1 754w, https://images.theconversation.com/files/84213/original/image-20150608-8692-1sfsbfg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=615&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/84213/original/image-20150608-8692-1sfsbfg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=615&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 hydraulic fracturing water cycle.</span>
<span class="attribution"><span class="source">US EPA</span></span>
</figcaption>
</figure>
<h2>What’s needed to make it safe</h2>
<p>The primary problem is clearly how to deal with the waste water. </p>
<p>There are mitigating factors. South Africa has excellent <a href="http://www.orangesenqurak.org/governance/water+governance+orange+senqu+basi/national+water+laws/south+africa.aspx">water legislation</a> and a reasonable level of enforcement. The Department of Water Affairs has more than <a href="http://www.da.org.za/archive/environmental-compliance-report-must-also-include-water-transgressions/">900 environmental inspectors</a>. Also, potential drillers are mainly large corporations who are well aware of the risks to their reputation if they are environmentally irresponsible. </p>
<p>The environmental impact caused by shale gas production is a tiny fraction of that <a href="http://link.springer.com/article/10.1007/s10584-011-0217-3">caused by coal mining</a>. The volume of the earth’s crust disturbed by a hole 15cm in diameter and 5km long is tiny in comparison to the 3km x 5km x 120m excavation of South Africa’s only <a href="http://www.exxaro.com/index.php/where-we-operate/coal/grootegeluk/">open cast coal mine</a>.</p>
<p>The geological location of a well determines how much water is used. In some parts of the US, each hole has needed about six <a href="http://stateimpact.npr.org/pennsylvania/2013/03/12/how-much-water-it-takes-to-frack-a-well/">Olympic size swimming pools of water</a>.</p>
<p>In the <a href="http://www.southafrica.net/za/en/articles/entry/article-southafrica.net-the-magical-great-karoo">Karoo</a>, a semi-arid region of South Africa, that is extravagant unless alternative supplies of water are found. <a href="http://www.karooshalegas.org/archives/10025">A survey</a> of deep groundwater has shown a huge lake more than 2km below surface between the <a href="http://www.mountainpassessouthafrica.co.za/find-a-pass/western-cape/item/121-outeniqua-pass-george.html">Outeniqua mountains</a> and the <a href="http://www.sa-venues.com/attractionswc/karoo-attractions.htm">Little Karoo</a>. </p>
<p>Accessing this water could benefit the region once the holes have been fracked. Reaching this water will require far deeper holes than is normally economical, and will need exactly the same sophisticated type of drills that will be needed for fracking. It is not certain at this stage how good the water quality will prove to be.</p>
<p>A final fear is that drilling is a noisy business because it needs heavy equipment. But technology has evolved to the point where a well can be brought into production in under two months. In addition, long horizontal runs have been developed making it possible for individual wells to be several kilometres apart.</p>
<h2>Hurdles before production can commence</h2>
<p>The North American example shows that this technology can be <a href="http://www.ft.com/cms/s/0/c6ab0abc-4e29-11e4-bfda-00144feab7de.html#axzz3c0N31Ul2">immensely profitable</a> for country’s economies. Cheap gas creates many opportunities for new businesses, for large corporates and potentially for communities.</p>
<p>The first hurdle to replicating this success in South Africa is that, while there is every indication that gas is present, it is unknown if it can be produced economically. It will take several years to drill and hydraulically stimulate a number of wells and begin to understand what will take to make the gas flow. </p>
<p>The South African government still has to give the go-ahead for exploration to start. There are some delays while it undertakes essential environmental investigations. The government has estimated that these will <a href="http://www.bdlive.co.za/national/science/2015/05/12/environmental-assessment-may-affect-rules-of-fracking">take three years</a>, but it is keen to start preliminary studies before the environmental investigations are complete.</p>
<p>The second hurdle is how to distribute the gas once it is available. That will involve treating the gas to ensure it is of a quality fit for distribution, and then setting up a network of pipes to carry the gas to customers. </p>
<p>New power stations will be the key drivers for developing a gas distribution network. This will lead to the creation of many other small industries that can use the clean source of heat which gas can provide. In one unpublished study, the arrival of gas stimulated around 300 small businesses and created more than 3000 jobs in the <a href="http://www.durban.gov.za/Pages/default.aspx">eThekweni municipality in Durban</a>, in Kwazulu-Natal.</p>
<p>Fracking has identifiable but manageable risks, and has the potential to solve many of the continent’s power problems. It is also able to create many jobs – not in production, but in using the gas that fracking could bring. It might also transform the economy as it has in North America.</p><img src="https://counter.theconversation.com/content/42271/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Philip Lloyd receives funding from National Research Foundation for work on improved cookstoves.</span></em></p>Fracking presents a better alternative to coal mining. Finding a way to produce the gas economically is the first challenge to getting fracking underway.Philip Lloyd, Research Professor of Energy, Cape Peninsula University of TechnologyLicensed as Creative Commons – attribution, no derivatives.