Botany & Zoology
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Can seabirds detect infrasound?http://www.sun.ac.za/english/Lists/news/DispForm.aspx?ID=5151Can seabirds detect infrasound?Wiida Fourie-Basson <p>​Can seabirds detect infrasound? And if yes, do they use it to navigate the vast oceans? <br></p><p>A physiological ecologist from Stellenbosch University (SU), Dr Susana Clusella-Trullas, will be charting unsailed waters as she sets out to answer this question in collaboration with a team of researchers from the USA, the United Kingdom (UK) and The Netherlands.</p><p>They have recently obtained a grant of R1.3 million from the International <a href="http://www.hfsp.org/">Human Frontier Science Program</a> as part of its <a href="http://www.hfsp.org/awardees/newly-awarded">Young Investigator Grants</a> for research into complex mechanisms of living organisms. </p><p>Seabird migration remains one of the phenomena in the animal kingdom that we still know very little about. Over the years scientists have managed to prove that some birds use the position of the stars and the earth’s magnetic field to find their way. More recently, a group from the <a href="http://www.dailymail.co.uk/sciencetech/article-4831622/How-seabirds-cross-ocean-using-sense-smell.html">universities of Oxford, Barcelona and Pisa</a>, demonstrated that shearwaters rely on their sense of smell to find their way back to their nests on land after foraging out over the ocean.</p><p>Dr Clusella-Trullas will be working with <span lang="EN-US">Jelle Assink, a g</span>eophysicist from the <span lang="EN-US">Royal Netherlands Meteorological Institute in The Netherlands; Samantha Patrick, a behavioral ecologist from the University of Liverpool in the UK; and Mathieu Basille, a spatial ecologist from the University of Florida in the USA.</span></p><p>The idea is to pool all their expertise in order to tackle this vexing question from every possible angle. </p><p>“As the physiological ecologist in the team, I will be examining the ear structures of various seabird species to test this hypothesis. Since some seabirds have tremendously long migrations, it is highly possible that they use infrasound as a medium to orientate, avoid storms and detect island shores. There are a few studies that suggest that homing pigeons can detect infrasound and some structures and mechanisms have been described for this group,” she explains.</p><p>As seabirds are often found as by-catch in fisheries, she will be obtaining fresh carcasses from various sources to do the research: “We will examine cross sections of the inner ear of these seabirds. Hopefully we will be able to identify the mechanisms that allow them to detect infrasound.” </p><p>As part of this process, she will also use 3D imaging techniques to look for the structures.</p><p>If they are able to identify the mechanisms that allow seabirds to detect infrasound, these will then be visualised and measured. The data will then be integrated by means of spatial modelling with data from the larger international collaborative project. </p><p>For more information about the project and their progress, visit the blog at <a href="https://seabirdsound.wordpress.com/">https://seabirdsound.wordpress.com/</a></p><p><em>On the photo above, Dr Susana Clusella-Trullas from SU's Department of Botany and Zoology. Photo: Stefan Els</em><br></p>
Sharksafe Barrier™ to compete in Innovation Summit’s pitching denhttp://www.sun.ac.za/english/Lists/news/DispForm.aspx?ID=5123Sharksafe Barrier™ to compete in Innovation Summit’s pitching denWiida Fourie-Basson<p>The Sharksafe Barrier™ – a cost-effective and environmentally friendly alternative to conventional anti-shark devices developed by researchers from Stellenbosch University (SU) and the University of Massachusetts Dartmouth – is one of the technologies that will compete for potential investment in the 'Pitching Den' during the SA Innovation Summit taking place in Cape Town this week.</p><p>The competition is part of the Global Cleantech Innovation Programme (GCIP-SA) – an international initiative that aims to address the most pressing energy, environmental and economic challenges of our time through promoting clean and innovative new technologies.</p><p>Dr Sara Andreotti, a marine biologist in SU's Department of Botany and Zoology, will be doing the pitching. She developed the Sharksafe Barrier™ in collaboration with Dr Craig O' Connell (University of Massachusetts Dartmouth), Michael Rutzen (white shark conservationist and shark cage diving operator) and Prof Conrad Matthee (head of the Department of Botany and Zoology at SU). </p><p>This innovative structure is composed of an array of black plastic pipes deployed in the ocean, to biomimic a kelp forest when viewed from within the water. The pipes are anchored to the sea-floor and are vertically buoyant.</p><p>“Our work indicates that kelp forests deter large predatory sharks and that they generally avoid swimming through them," explains Dr Andreotti.</p><p>Furthermore, to enhance the effectiveness of the barrier, ceramic magnets are arranged along the length of the artificial kelp forest. Previous work showed that magnets deter shark species, including great white sharks, bull sharks, tiger sharks and hammerhead sharks.</p><p>The concept has been tested in Gansbaai, the mecca of South Africa's great white sharks. The research team built an underwater exclusion zone of 13 x 13 metres, and attracted sharks to the middle using bait. After 34 trials, and with 255 hours of video footage collected over two years, not a single white shark entered the zone. Smaller fish, like skates, herring and mallets, did enter the exclusion zone and moved freely between the kelp-like structures.</p><p>The results from this project was published in the journal <em>Aquatic Conservation: Marine and Freshwater Ecosystems </em>recently, with the title “<a href="http://onlinelibrary.wiley.com/doi/10.1002/aqc.2803/abstract">Testing the exclusion capabilities and durability of the Sharksafe Barrier<span><span>™</span></span> to determine its viability as an eco-friendly alternative to current shark culling methodologies</a>".</p><p>The Sharksafe Barrier™ concept has been patented by SU, and has been accepted in Australia (2013350811) and Europe (13821175.0), with applications pending in Brazil (BR112015012008-3), the USA (14/647,646) and South Africa (2015/04471).  (F2016/00959; F2016/00960; F2016/00961; F2016/00962). The Shark Barrier End Caps concept (F2016/00959; F2016/00960; F2016/00961; F2016/00962) has been granted as a functional design in South Africa.</p><p>Dr Andreotti says the technology addresses two major issues: the unjustified loss of human lives and the equally unjustified loss of marine life (whales, turtles, dolphins and sharks) due to the use of shark nets and drumlines: “Between 2011 and 2016 there have been 491 registered shark attacks worldwide, of which 43 proved to be fatal. Over the past 20 years, however, almost 4 000 sea creatures have been caught in shark nets lining the beaches of New South Wales in Australia alone."</p><p>Tourism is another important reason for protecting the world's great whites. In South Africa, the local white shark diving tourism industry is worth US$4.4 million a year: “The temporary disappearance of white sharks in 2017 has already forced one of the eight cage diving companies to suspend their activities" she warns.</p><p>The popular tourist destination, La Réunion Island, experiences on average a 40% loss in bookings after a shark attack. Between 2011 and 2016, there have been 19 shark attacks in this area, forcing the authorities to permanently close one of the beaches, she adds.</p><p>As part of the Global Cleantech programme, the public is invited to participate in an <a href="https://docs.google.com/forms/d/e/1FAIpQLScZVSYlk7IRJY3wFzDPH0-2QxaY_q_VC2HvG7TKnAFsDHvA0A/viewform">opinion survey</a> about beach safety and people's perceptions about sharks and shark conservation. <a href="https://docs.google.com/forms/d/e/1FAIpQLScZVSYlk7IRJY3wFzDPH0-2QxaY_q_VC2HvG7TKnAFsDHvA0A/viewform">Click here</a> to participate.</p><p><em>Photos: </em><span><span><em>Daniel Botelho</em></span></span><br></p>
Oceans are key to our survivalhttp://www.sun.ac.za/english/Lists/news/DispForm.aspx?ID=4941Oceans are key to our survivalSophie von der Heyden<p>Thursday (8 June 2017) is World Oceans Day. In an article published on The Conversation website on Tuesday (6 June 2017), Prof Sophie von der Heyden, from the Department of Botany and Zoology, writes that we must look after our oceans because without them our chances of survival are low.</p><ul><li>Read the complete article below or click <a href="https://theconversation.com/a-tribute-to-the-worlds-oceans-why-we-couldnt-survive-without-them-78945" style="text-decoration:underline;"><strong class="ms-rteThemeForeColor-5-0" style="text-decoration:underline;">here</strong></a> for the piece as published. <br></li></ul><p><strong>Time to reflect on the big blue</strong></p><p><strong>S</strong><strong>ophie von der Heyden</strong>*</p><p>World Oceans Day, an international event that is commemorated on the 8th June every year, is a chance to reflect on the importance of oceans, whether you live next to the sea or many thousands of kilometres inland. Most of us do not realise the impact of the oceans on our daily lives, nor how humanity has changed vast parts of the big blue and its inhabitants. About one quarter of all species live in the sea (roughly about 2.2 million, with the current estimates of all species on earth at about 8.7 million) and their linkages with us are far-reaching and more pervasive than we can imagine.</p><p><strong>Oceans are key to our survival</strong></p><p>Water covers about 71% of the planet's surface, which means that it is not only home to much of life on earth, but it is also closely involved in many functions that provide a stable environment for life to thrive. For example, oceans are an integral part of our weather and climate patterns, absorbing, storing and redistributing heat through currents and they play a critical role in maintaining stable climates. They are also the largest absorbers of carbon dioxide (CO2), one of the greenhouse gasses that actively contribute to global warming. </p><p>Oceans absorb about one quarter of all CO2 produced by human activities, providing an invaluable service to life on land, especially in mitigating some of the effects of human driven climate change. In addition, microscopic plants, called phytoplankton produce between half to 70% of all oxygen. To put this into perspective, researchers have tried to calculate how much oxygen humans use just for breathing, a figure that comes to over 6 billion tonnes of oxygen per year. </p><p>The oceans also provide many other important benefits; they have been extensively used to transport goods around the globe and they are a source of renewable energy from the action of wind and waves. Marine waters are also a potential goldmine for the pharmaceutical industry with some bacteria, sponges and algae showing great promise for treatments for diseases such as cancer. It is difficult to put a price on all of this, but researchers have tried to provide a monetary estimate of all that the oceans provide for humanity and arrived at a conservative value of a about US$2.5 trillion per year. Add to that the spiritual and cultural benefits and the sheer fun of being at the beach and the list of ocean services becomes very impressive. </p><p><strong>So why a World Oceans Day?</strong></p><p>If it isn't a 'catch of the day', we tend to forget about the myriad of life beneath the waves. This diversity is fantastic, from tiny microscopic plants and animals to the largest mammal that has ever existed on earth, the blue whale. Ocean life has evolved to inhabit many different kinds of environments, from the ocean surface to the deepest known point at about 11,000m and a range from frozen seas to tropical coral reefs. World Oceans Day celebrates this diversity and reminds us of the importance of the big blue. It also serves to highlight the plight that the oceans are facing from continued anthropogenic pressures. </p><p>Most people are aware that many of the fish, crustacean and shellfish stocks in South Africa and beyond are overfished and that the bounty of the sea is a fraction of what it should be. With over a billion people relying on protein provided directly by the ocean, it is easy to how much pressure humans are putting on natural resources. </p><p>Climate change too has contributed towards changing the temperatures and chemistry of the oceans. As the levels of CO<sub>2</sub> have been increasing in the atmosphere, so has the uptake of this gas into marine waters. The next effect has been that some parts of the ocean are getting more acidic, which is a real problem for some animals and plants that rely on calcium carbonate as part of their bodies, that are literally dissolving in these new environments. </p><p>In addition, temperatures have also been changing in the oceans, which has led to large-scale shifts in marine life; for example, in their search for cooler some fish species in the North Atlantic have been documented to shift their ranges towards the North Pole or into greater depths. Pollution, as effluent, agricultural run off that includes fertilisers and pesticides and plastics are also heavily contributing towards killing marine species at unprecedented rates.</p><p>As a global collective, with many of us living far from the coastline, we need to become more aware of the far-reaching consequences of our daily activities and how these play out not only on land, but also in the sea. All of us should be contributing towards the safeguarding of the big blue, because without it the chances of our own survival are very low indeed. So let's celebrate World Oceans Day and with it our future.   </p><p>---------------------</p><p>*<em>Sophie von der Heyden is an Associate Professor of Marine Genomics and Conservation in the Department of Botany and Zoology at Stellenbosch University. She is the author of the popular 'Southern African Seashores – a Guide for Young Explorers' (2012) published by Struik Nature. </em></p><p><br></p>
Book donation boosts Iimbovane ant projecthttp://www.sun.ac.za/english/Lists/news/DispForm.aspx?ID=4935Book donation boosts Iimbovane ant projectMedia and communication, Faculty of Science<p>The Iimbovane Outreach Project has received a generous donation of books, which will be used to help in the teaching of biodiversity science to the high school learners.  </p><p>The donation of 50 copies of the first ever guide to ants of Southern Africa, was made possible by the Mapula Trust and the author, Peter Slingsby. While Peter is well renowned for his maps, he is also an avid ant enthusiast and author of several books on rock art of the southern Cape and Cederberg. </p><p>His new book, <em>Ants of Southern Africa: a Friendly Guide</em> was published in March 2017.<img src="/english/PublishingImages/Lists/dualnews/AllItems/Coverantbook.jpg" alt="Coverantbook.jpg" class="ms-rtePosition-1" style="margin:5px;width:191px;height:248px;" /> </p><p>The donation was handed over during a presentation by Peter where he explained how his lifelong passion for ants translated into a brilliant new field guide. His passion started from a young age, sparked by a book written by the eminent South African entomologist, Sydney Harold Skaife, and continued throughout his adult life. </p><p>What struck Peter was the lack of knowledge on ants freely available to the public. He decided to solve this by writing the book which contains high quality photographs of live ants. </p><p>"<em>Botanists use dried plants in herbaria, which the public will get bored of, as the need to see the live plants to gain interest; similarly, scientists need pinned ants in a reference collection for studies, the public however, need to see live ants</em>" explains Peter.<img src="/english/PublishingImages/Lists/dualnews/AllItems/IMG_3567.jpg" alt="IMG_3567.jpg" class="ms-rtePosition-2" style="margin:5px;width:410px;height:361px;" /> </p><p>With inputs and guidance from some of the world's leading experts, Peter has filled 256 full-colour pages with descriptions of some 250 species, with mentions of 400 more. The book<em> </em>is filled with fabulous drawings by Peter, photographs by Philip Herbst, and the best of fifty images from <a href="https://www.ispotnature.org/communities/southern-africa">iSpot</a> contributors. <a href="https://www.ispotnature.org/communities/southern-africa">iSpot</a> is an online community wherein anyone can post and contribute to identification of photographs of any living organism. </p><p>Over the years, Peter has worked with several environmental education organisations, teaching children about ants and myrmechochory (seed dispersal by ants). Upon hearing about the work that Iimbovane does, Peter, with the financial support from the Mapula Trust, donated 50 copies of the guide book to the <a href="file:///C:/Users/dorette/AppData/Local/Microsoft/Windows/Temporary%20Internet%20Files/Content.Outlook/WXDH7L5V/www0.sun.ac.za/iimbovane">Iimbovane ant project</a>. </p><p><a href="file:///C:/Users/dorette/AppData/Local/Microsoft/Windows/Temporary%20Internet%20Files/Content.Outlook/WXDH7L5V/www0.sun.ac.za/iimbovane">Iimbovane</a> is a science outreach project, based at the Stellenbosch University, which uses ants as a model species to teach learners about biodiversity and science.  </p><p>"<em>This is a very welcome addition to the resources of the Iimbovane project. We will use the donated books during our workshops and field excursions to introduce learners to the full diversity of the species. The brilliant photographs and ants facts will be used to enrich our classroom lessons on ant biology, their social behaviour and biological classification. These books are instrumental in our efforts to educate the youth about biodiversity</em>" says Dorette du Plessis, from the <a href="file:///F:/www0.sun.ac.za/iimbovane">Iimbovane ant project</a>. </p><p>For more information about the book, contact Peter at <a href="mailto:slingsby@icon.co.za">slingsby@icon.co.za</a></p><p>The book can be ordered from <a href="http://www.slingsbymaps.com/">www.slingsbymaps.com</a> <br></p><p><em>On the photo, Dorette du Plessis from the Iimbivane-ant project with the writer, Peter Slingsby</em><br></p>
SU researchers aim to grow research collaboration with African countrieshttp://www.sun.ac.za/english/Lists/news/DispForm.aspx?ID=4817SU researchers aim to grow research collaboration with African countriesWiida Fourie-Basson<p>'Orphan crops' and the impact of an invasive weed on subsistence farmers in Nigeria are two of the topics Stellenbosch University (SU) researchers will investigate as part of a research visit funded by SU's Centre for Collaboration in Africa (CCA) and the International Foundation for Science (IFS).</p><p>Dr Ethel Phiri and Dr Natasha Mothapo, postdoctoral fellows in SU's departments of genetics and botany and zoology, are visiting the University of Lagos from 17 to 22 April 2017. During this time they will both present seminars, while Dr Mothapo will conclude the final stage of a research project into subsistence farmers' perceptions and use of orphan crops.</p><p>They will also be hosted by Prof. Linus Opara, holder of the S<a href="/english/faculty/agri/postharvest-technology/Pages/default.aspx">ARChI research chair in postharvest technology </a>at SU and currently on sabbatical in Nigeria.</p><p>Their main aim is to establish and grow networks with African universities in order to strengthen the African research agenda: "As young and emerging researchers in South Africa, we have a vested interest in African research and would like to maintain the focus of our research within the continent," they comment.</p><p>Dr Mothapo, who is also team coordinator of a collaborative project funded by the IFS, will use the opportunity to complete a survey investigating the socio-economic impacts of an invasive weed on subsistence farmers and their perceptions thereof.</p><p>She explains: "Farmers perceive some invasive plant species as being good in improving soil fertility, but often these plants cause damage to crops and reduce yield significantly. These perceptions also limit invasive species management plans.</p><p>"We will also talk to farmers to understand how they use and perceive orphan and other underutilised crops. While the major food crops like maize, wheat and rice dominate global production, so-called orphan crops have the potential to be of economic and agronomic significance for developing countries struggling with food security and climate change," she adds.</p><p>In Sub-Saharan Africa, for example, orphan crops like sorghum and millets are more important than rice and wheat.  However, because they are not traded internationally, orphan crops have received less attention in terms of research and agricultural training.</p><p>"We are the generation of researchers that should be focusing on Africa's research problems," Dr Phiri concludes.<br></p><p><em>Op die foto, dr. Ethel Phiri (links) en dr. Natasha Mothapo. Foto: Wiida Fourie</em><br></p><p><br></p>
Climate change impacts felt from genes to ecosystemshttp://www.sun.ac.za/english/Lists/news/DispForm.aspx?ID=4477Climate change impacts felt from genes to ecosystemsMedia & Communication, Faculty of Science<span><p></p><p>New research published in <em>Science</em> today shows that climate-change impacts have already impacted every aspect of life on Earth from genes to entire ecosystems, with increasingly worrying consequences for humans.</p><p>The article, "The broad footprint of climate change from genes to biomes to people", co-authored by Dr Wendy Foden from Stellenbosch University, has been published in <em>Science</em> today (11 November 2016). Dr Foden is also chair of the International Union for the Conservation of Nature's (IUCN) Species Survival Commission and Climate Change Specialist Group (CCSG) where the study originated. </p><p>In the study, researchers identified a set of core ecological processes that underpin the functioning of healthy ecosystems. Of the 94 processes considered and published in peer-reviewed literature, 82% showed robust evidence of impacts from climate change. These impacts include changes to genetic diversity or seasonal migration, all which influence the functioning of healthy marine, freshwater and terrestrial ecosystems.</p><p>"These climate change impacts are deeply concerning, and are more extensive than we expected. It is clear that climate change is a major concern, not for the future, but now,"<em> </em>Dr Foden says.<strong> </strong></p><p>Dr Brett Sheffers, lead author of the article from the University of Florida and also a member of the IUCN SSC CCSG group, says they now have evidence that, with only a ~1<sup>o</sup>C of warming globally, major impacts are already being felt. These range from individual genes changing, significant shifts in species' physiology and physical features such as body size, to species moving to entirely new areas<em>.</em></p><p>The researchers warn that the many observed impacts of climate change at different levels of biological organisation points to an increasingly unpredictable future for humans in terms of food security and human health. Healthy ecosystems contribute to climate mitigation and adaption by sequestering substantial amounts of carbon, regulating local climate and reducing risks from climate-related hazards such as floods, sea-level rise and cyclones, the report states. </p><p>"This study has strong implications for the world leaders gathering for climate negotiations in Marrakesh." says Dr Foden. "Countries are currently committing to reduce global temperature rise to around 3<sup>o</sup>C. But we are showing that there are already serious impacts right across biological systems at an increase of only 1<sup>o</sup>C. If we are going to keep natural systems delivering the services we rely so heavily on, it is imperative that we step up our efforts."</p><p>She says many of these impacts have already been observed in Africa. A <a href="http://onlinelibrary.wiley.com/doi/10.1111/j.1472-4642.2007.00391.x/abstract%3bjsessionid=97D8AE3C31AEEDEF1EDCB290C0727911.f03t04">2007 study</a> found that Southern Africa's Quiver Trees (<em>Aloe dichotoma</em>) have been suffering from high mortality and poor reproduction in their hot, arid northern distribution range in Namibia due to increased drought stress. However, at their southern range edge in South Africa, where conditions were previously at the limit of their tolerance for cool, wet conditions, populations have been rapidly expanding.</p><p>A <a href="http://www.pnas.org/content/113/34/9563">2016 study</a> attributes declining fishing yields from Africa's Lake Tanganyika to changes in lake circulation due to warming of surface waters. Other studies have documented the impact of climate change on food security, such as the decline of maize yields in Africa. The outbreak of diseases such as <em>Babesia</em> and canine distemper virus (CDV) in 1994 and 2001 that killed over one-third of the <a href="http://phenomena.nationalgeographic.com/2008/06/24/lions-killed-by-perfect-storm-of-changing-climate-virus-and-parasites/">Serengeti lion population</a> was also the result of a cycle of processes, initiated by climate change. Researchers attributed the disease-outbreak to a combination of viral infections, blood parasites and extreme weather events.</p><p>Prof Guy Midgley, head of the global change biology research group in SU's Department of Botany and Zoology, says the Science paper highlights what they have been seeing on the ground in South Africa: "Climate change impacts have now become wide-spread and are accumulating more quickly than we expected. It is essential that we act decisively and quickly to reduce our greenhouse gas emissions worldwide." </p><p>The full study can be accessed here. </p><p><strong>Media interviews</strong></p><p>Dr Wendy Foden</p><p>E: fodenw@gmail.com</p><p>Tel: +44 793 280 4214</p><p>Skype: wendyfoden; </p><p> </p><p>Prof. Guy Midgley</p><p>E: <a href="mailto:gfmidgley@sun.ac.za">gfmidgley@sun.ac.za</a></p><p>Tel: +27_21 808 3223</p></span>