Characterization of arbuscular mycorrhizal fungal species associating with Zea mays
- Authors: Maússe-Sitoe, Silvia , Dames, Joanna F
- Date: 2024
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/440339 , vital:73775 , https://doi.org/10.3389/fpls.2024.1345229
- Description: Taxonomic identification of arbuscular mycorrhizal (AM) fungal spores extracted directly from the field is sometimes difficult because spores are often degraded or parasitized by other organisms. Single-spore inoculation of a suitable host plant allows for establishing monosporic cultures of AM fungi. This study aimed to propagate AM fungal spores isolated from maize soil using single spores for morphological characterization. First, trap cultures were established to trigger the sporulation of AM fungal species. Second, trap cultures were established with individual morphotypes by picking up only one spore under a dissecting microscope and transferring it to a small triangle of sterilized filter paper, which was then carefully inoculated below a root from germinated sorghum seeds in each pot and covered with a sterile substrate. All pots were placed in sunbags and maintained in a plant growth room for 120 days.
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- Date Issued: 2024
Regimes of truth regarding ‘sexual justice’ in academic literature from 2012 to 2022: a scoping review
- Authors: Pinto, Pedro , Macleod, Catriona I , Jones, Megaera
- Date: 2024
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/461013 , vital:76073 , https://doi.org/10.1080/13691058.2024.2386051
- Description: The notion of ‘sexual justice’ has gained traction in academic and policy arenas in recent years. This paper presents a scoping literature review of the regimes of truth, following Foucault, of ‘sexual justice’ appearing in the scientific literature from 2012 to 2022. Thirty-eight papers were coded using (1) content analysis of the studies’ central problematics, the programmes referred to, and institutional location(s); and (2) thematic analysis of how the notion was deployed. Central problematics centred on (1) critiques of, or alternatives to, dominant approaches to sexual and reproductive health; and (2) highlighting injustices. As such, ‘sexual justice’ is fighting for legitimacy in the truth stakes. There is a distinct paucity of papers tackling the translation of ‘sexual justice’ into practice. South Africa dominates as the site in which papers on ‘sexual justice’ have been produced, but there is a lack of South-South collaboration. Two themes were apparent around which conceptions of sexual justice cohere. Firstly, sexual justice is seen as a vital, yet politically ambivalent goal, with neoliberal co-optation of progressive rights agendas being warned against. Secondly, sexual justice is viewed as a means, in which sexual justice is described as having potential to repair established frameworks’ shortcomings and oppressive legacies.
- Full Text:
- Date Issued: 2024
Recent progress in the conversion of agricultural waste into functional materials
- Authors: Xhamla, Nqoro, Raymond Taziwa,Patricia Popoola
- Date: 2023
- Language: English
- Type: text , Article
- Identifier: http://hdl.handle.net/11260/9238 , vital:73025
- Description: Agricultural waste is enriched with a variety of environmentally friendly materials that can potentially boost economic growth, reduce the spread of contagious diseases, and serve as a carbon-free renewable energy bioresource. Biopolymers produced from agricultural waste have a range of applications in medicine, agriculture, pharmaceutics, and industrial factories. The chemical extraction of biopolymers from biomass requires a series of alternating alkali, acid, and alkali treatments at controlled temperatures. Chemical extraction of plant-based biopolymers requires elevated temperatures (70–100°C), while for animal and sea organism-based biopolymers, moderate temperatures of 25–60°C are used. The obtained biopolymers are functionalized into various materials for application in a wide range of industries. The reported functional materials are loaded with inorganic nanomaterials, plant extracts, and organic compounds, which resulted in a synergistic effect and enhanced activity of the materials. Several researchers have synthesized biopolymers with synthetic polymers to improve their bioavailability, tensile strength, shelf life, and UV adsorption. This review article reports the extraction techniques of biopolymers from agricultural waste and their application in wound healing, water treatment, food storage, passive cooling, and cosmetics. The dearth of scientific articles on the applications of biopolymers generated from agricultural waste produced from food crops grown in Africa is a motivation for the present compilation.
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- Date Issued: 2023
The Case for a Cray on a Chip
- Authors: Machanick, Philip
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/439277 , vital:73561 , https://www.researchgate.net/profile/Siphamandla-Mncu-be/publication/375376322_Shadow_Information_Technology_in_the_Advent_of_Open_Educational_Resources/links/65485042ce88b87031c92188/Shadow-Information-Technology-in-the-Advent-of-Open-Educational-Resources.pdf#page=22
- Description: Moore’s Law is usually interpreted as a prediction of how many transistors you can buy for the same money at some future date. It can also be interpreted as how long you need to wait until a given number of transistors falls below a target price. An example of this reverse-application of Moore’s Law is transitions such as the emergence of microprocessors competitive with traditional larger-scale computers and the emergence of smartphones. Since the late 1990s, it has become increasingly common for growth in transistors to equate to more CPUs (cores) per die. Recent designs have over 50 billion transistors and far more potential parallelism than can be supported by memory. I argue the case for a rebalancing of design goals with a much larger, faster on-chip memory and a CPU that is designed around this memory system. The proposal: a Cray-class vector CPU on a die with 1 Gibyte of static RAM, or Crayon (for Cray on a chip). The kind of organization classically used by Cray vector supercomputers is feasible to achieve on a single chip. I argue that a design like this can use the available memory bandwidth, as opposed to over-CPU designs with a large number of cores and GPU threads that are memory limited and propose how such a design could be used.
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- Date Issued: 2023
Tragic Optimism: A Psychobiography of Morgan Richard Tsvangirai.
- Authors: Harry, Tinashe T , van Niekerk, Roelf
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/434439 , vital:73060 , ISBN 978-3-031-28826-5 , https://link.springer.com/chapter/10.1007/978-3-031-28827-2_5
- Description: For many Zimbabweans, Morgan Richard Tsvangirai (1952–2018) became the face of courage and hope during his political career. Tsvangirai was subjected to and witnessed political violence, physical abuse, brutality, emotional humiliation, unlawful detentions, and persecution. He challenged the ruling party in Zimbabwe, and his leadership gave many people hope for the future. In the context of living in a colonial era, poverty, and having to endure the brutality of the Mugabe era, he lived a meaningful life that saw him becoming a Prime Minister of Zimbabwe (2009–2013). This single-case study explores and describes Tsvangirai’s life and interprets it in terms of Frankl’s existential theory. More specifically, Tsvangirai’s life is interpreted from the perspective of Frankl’s three triads, the fundamental, meaning, and tragic triads, as well as the noetic dimension. Tsvangirai was selected through purposive sampling based on his important role in Zimbabwean politics. The primary source of data was biographical and autobiographical publications. The findings indicate that Tsvangirai shifted emphasis within the meaning triad in living a meaningful life and that he was able to use the human capacity of self-distancing/detachment and self-transcendence to find meaning in his life. This chapter sheds light on how individuals make sense of their circumstances and search for meaning and purpose in adverse conditions. It also contributes towards the development of psychobiographical research among non-WEIRD samples.
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- Date Issued: 2023
Can Local Knowledge of Small-Scale Fishers Be Used to Monitor and Assess Changes in Marine Ecosystems in a European Context?
- Authors: Piñeiro-Corbeira, Cristina , Barrientos, Sara , Barreiro, Rodolfo , Aswani, Shankar , Pascual-Fernández, José , De la Cruz-Modino, Raquel
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/391331 , vital:68642 , ISBN 978-3-031-01980-7 , https://doi.org/10.1007/978-3-031-01980-7_24
- Description: Significance Statement In the last decades, many coastal areas have observed dramatic changes in marine ecosystems, due to anthropogenic and environmental alterations. The general absence of long-term data sets in the marine environment and, more specifically, on benthic and demersal communities represents a severe issue for management and conservation. We propose to incorporate the small-scale fishers’ knowledge and science for better policy recommendations, both in terms of fisheries optimization and resource conservation. Based on two different cases of study with diverse ecosystems, we explore the combination of quantitative and qualitative tools, and participative techniques used to incorporate fishers’ local ecological knowledge. The results highlight fishers’ capacity to identify coastal and marine landscapes resources and changes, reinforcing and complementing the scientific assessment.
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- Date Issued: 2022
Digitalisation and Transformative Learning for Sustainable Futures in Rural Africa Leaving No One Behind
- Authors: Shetye, Nyanta , Lotz-Sisitka, Heila , Albrecht, Eike , Durr, Sarah , Marx, Dirk , Chirambo, Dumisani , Metelerkamp, Luke , van Zyl-Bulitta, Verena
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/435263 , vital:73143 , ISBN 9781928502241 , https://www.taylorfrancis.com/chapters/oa-edit/10.4324/9781003274322-14/digitalisation-transformative-learning-sustainable-futures-rural-africa-niyanta-shetye-heila-lotz-sisitka-eike-albrecht-sarah-durr-dirk-marx-dumisani-chirambo-luke-metelerkamp-verena-van-zyl-bulitta
- Description: This chapter assesses the use of Information and Telecommunication Technologies (ICTs) for social and community learning to achieve sustainable development in rural communities in Africa. It focuses on new and emerging trends in the cooperation between the African Union and European Union (AU–EU) and links two thematic areas; namely green transitions and digital transformations. The chapter highlights low-cost and effective digital learning solutions. It is based on a literature review and cases that provide insight into potential AU–EU cooperation and the “leave no one behind” agenda. The chapter argues that in addition to digital technology transfer, innovation and investments are needed in building a learning-centred support for green transitioning and digital cooperation. Hence, we focus on transformative learning opportunities and informal Education for Sustainable Development (ESD). In response to ICTs becoming a catalyst for such a transformation, we seek insights into how constructive AU–EU cooperation and co-learning can pave ways for societal transformations, particularly in rural communities.
- Full Text:
- Date Issued: 2022
Developing Rural Economies through Small to Medium Tourism Enterprise: the case of Matatiele and Cedarville in the Eastern Cape, South Africa
- Authors: Mxunyelwa, Siyabonga , Matarinano, Obert , Vallabh, Dinesh
- Date: 2021
- Subjects: Matatiele, South Africa Small and medium-sized enterprises Small Business Computer File
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/6015 , vital:45081 , https://www.ijicc.net/index.php/ijicc-editions/2021/226-vol-15-iss-10
- Description: Globally, nations depend on small businesses as engines for economic growth. Small to Medium Tourism Enterprises (SMTEs), as part of the small business sector, are increasingly becoming important in terms of job creation, wealth creation and driving economic growth in smaller rural geographic areas. Utilising a mixed research approach, the paper identifies characteristics of SMTEs in Matatiele and Cedarville with the intention of identifying specific ways in which they can be supported to attain their real potential in enabling economic development in rural environment. Purposive sampling method was used to select respondents and self-administered questionnaires utilised to gather relevant data from managers/owners. The results indicate that the rural tourism is dominated by female-owned enterprises primarily offering accommodation services. Most of the enterprises have been in operation for a period of more than five years which points to potential growth as they are able to survive. The results further show that the businesses that participated in the survey intent employing more full-time employees. Furthermore, the results underscore that there is lack of local government support to promote entrepreneurship in the SMTEs sector particularly those that are located in the rural environment. The findings elucidate the ability of SMTEs to greatly reduce the high unemployment in rural economies if appropriate systems are put in place to support these enterprises. These findings have implications for the national, provincial and local government spheres in South Africa in their quest to create job opportunities in rural areas through entrepreneurship and SMTEs in order to provide impetus to the Eastern Cape Province and South African Economy. This paper
- Full Text:
- Date Issued: 2021
Futures analysis
- Authors: Hichert, Tanya , Biggs, Reinette , de Vos, Alta
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/433871 , vital:73006 , ISBN 9781000401516 , https://library.oapen.org/handle/20.500.12657/49560
- Description: Futures analysis methods can help people to think constructively and systematically about the future and advance our understanding of change and uncertainty in complex social-ecological systems (SES). This is important because there is not one single predictable future but multiple ones, depending on the complex, unpredictable interplays and interactions of actors, institutions, ecological processes and other elements of the system and its dynamics. Actively developing ideas, images and/or stories about different futures can enable us to make different choices and take different actions in the present in relation to, for example, risk mitigation, adaptation, resource allocation and strategy development, which can help build more sustainable and just futures.
- Full Text:
- Date Issued: 2021
Mapping Computational Thinking Skills to the South African Secondary School Mathematics Curriculum
- Authors: Bradshaw, Karen L , Milne, Shannon
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/440285 , vital:73763 , ISBN 9783030950033 , https://doi.org/10.1007/978-3-030-95502-1_41
- Description: Computational thinking (CT) is gaining recognition as an important skill for learners in both Computer Science (CS) and several other disciplines, including mathematics. In addition, researchers have shown that there is a direct correlation between poor mathematical skills and the high attrition rate of CS undergraduates. This research investigates the use of nine core CT skills in the South African Grades 10–12 Mathematics curriculum by mapping these skills to the objectives given in each of the topics in the curriculum. The artefact developed shows that all the identified CT skills are used in the curriculum. With the use of this mapping, future research on interventions to develop these skills through mathematics at secondary school, should produce school leavers with better mathematical and problem solving abilities, which in turn, might contribute to better success rates in CS university courses.
- Full Text:
- Date Issued: 2021
Potential repurposing of four FDA approved compounds with antiplasmodial activity identified through proteome scale computational drug discovery and in vitro assay
- Authors: Diallo, Bakary N , Swart, Tarryn , Hoppe, Heinrich C , Tastan Bishop, Özlem , Lobb, Kevin A
- Date: 2021
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/177531 , vital:42830 , https://doi.org/10.1038/s41598-020-80722-2
- Description: Malaria elimination can benefit from time and cost-efficient approaches for antimalarials such as drug repurposing. In this work, 796 DrugBank compounds were screened against 36 Plasmodium falciparum targets using QuickVina-W. Hits were selected after rescoring using GRaph Interaction Matching (GRIM) and ligand efficiency metrics: surface efficiency index (SEI), binding efficiency index (BEI) and lipophilic efficiency (LipE). They were further evaluated in Molecular dynamics (MD). Twenty-five protein–ligand complexes were finally retained from the 28,656 (36×796) dockings.
- Full Text:
- Date Issued: 2021
The politics of postgraduate education: supervising in a troubled world
- Authors: McKenna, Sioux
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/434502 , vital:73069 , ISBN 9781991201225 , https://www.google.co.za/books/edition/The_Global_Scholar/KvQ3EAAAQBAJ?hl=enandgbpv=0
- Description: In our rapidly globalising world, "the global scholar" is a key concept for reimagining the roles of academics at the nexus of the global and the local. This book critically explores the implications of the concept for understanding postgraduate studies and supervision. It uses three conceptual lenses - "horizon", "currency" and "trajec-tory" - to organise the thirteen chapters, concluding with a reflection on the implica-tions of Covid-19 for postgraduate studies and supervision. Authors bring their perspectives on the global scholar from a variety of contexts, including South Afri-ca, Australia, the United States, the United Kingdom, Chile, Germany, Cyprus, Kenya and Israel. They explore issues around policy, research and practice, sharing a con-cern with the relation between the local and the global, and a passion for advancing postgraduate studies and supervision.
- Full Text:
- Date Issued: 2021
The practice and design of social-ecological systems research
- Authors: de Vos, Alta , Maciejewski, Kristine , Bodin, Orjan , Norstrom, Albert , Schluter, Maja , Tengo, Maria
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/433826 , vital:73003 , ISBN 9781000401516 , https://library.oapen.org/handle/20.500.12657/49560
- Description: Studying social-ecological systems (SES) can be a challenging task, as explained in Chapter 2. Phenomena of interest and characteristics of SES research result from both social and ecological processes, and complicated feedback dynamics blur the distinction between cause and effect (Young et al. 2006). Furthermore, multiple causal processes may be operating simultaneously, outcomes are strongly influenced by the system’s context and it is difficult to determine system boundaries (Bodin and Prell 2011).
- Full Text:
- Date Issued: 2021
Willem Anker’s Red Dog, Cormac McCarthy, and the Enigma of Coenraad de Buys
- Authors: Cornwell, Gareth D N
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/458217 , vital:75724 , https://hdl.handle.net/10520/ejc-iseaeng_v48_n2_a1
- Description: Willem Anker has been accused of stealing from Cormac McCarthy’s Blood Meridian (1985) in his novel Red Dog (2018), the English translation of his award-winning Buys (2014). I defend Anker on the charge of plagiarism, while conceding that his novel could not have been the book that it is without the precedent of Blood Meridian. I go on to voice other reservations about Red Dog via discussion, inter alia, of Anker’s characterisation of Coenraad Buys and the rendering in English of his Afrikaans original. I conclude that the historical Coenraad Buys appears intractable to novelistic treatment, and that Anker signals his awareness of this while at the same time making a valiant attempt to bring the character to life.
- Full Text:
- Date Issued: 2021
Body mass and condition of a fynbos bird community investigating impacts of time, weather and raptor abundance from long-term citizen-science datasets
- Authors: Lee, Alan T K , Barnard, Phoebe , Fraser, Mike , Lennard, Chris , Smit, Ben , Oschadleus, Hans-Dieter
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/441546 , vital:73897 , https://doi.org/10.2989/00306525.2019.1683093
- Description: Variation in body size, especially mass, is a function of local environmental conditions for any given species. Recent recorded decreases in body size of endotherms have been attributed to climate change in some cases. This prediction is based on the trend of smaller body size of endotherms in warmer climates (Bergmann’s rule) and it implies genetic responses rather than phenotypic flexibility. Alternatively, selection for smaller body size or lower mass could be explained by the starvation-predation hypothesis, where lighter individuals have a higher probability of escaping pursuing predators, such as raptors. Evidence that climate warming is driving patterns of size selection in birds in recent times has been mixed. We inspected data on 40 bird species contributed by bird ringers to the South African Ringing Scheme (SAFRING) for changes in body mass and condition as a function of time (year), minimum temperature of the day of capture, maximum temperature of the previous day, and rainfall data in the south-western Cape Floristic Region (fynbos) around Cape Town, South Africa, for the period 1988–2015. The region shows a warming trend over the study period (0.035 °C yr−1). Interannual body mass and condition change were poorly explained by year or temperature. High daily minimum temperature explained loss of body condition for four species, whereas evidence from recaptured birds indicated negative effects of increasing maximum daily temperature, as well as rain. For the alternative hypothesis, because raptor abundance is stable or only weakly declining, there is little evidence to suggest these as a driver influencing mass trends. Any decrease in body mass over the study period that we observed for birds appear more likely to be plastic responses to stress associated with temperature or rainfall at this time, rather than systematic selection for smaller body size, as predicted by Bergmann’s Rule.
- Full Text:
- Date Issued: 2020
Body mass and condition of a fynbos bird community investigating impacts of time, weather and raptor abundance from long-term citizen-science datasets
- Authors: Lee, Alan T K , Barnard, Phoebe , Fraser, Mike , Lennard, Chris , Smit, Ben , Oschadleus, Hans-Dieter
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/448383 , vital:74726 , https://doi.org/10.2989/00306525.2019.1683093
- Description: Variation in body size, especially mass, is a function of local environmental conditions for any given species. Recent recorded decreases in body size of endotherms have been attributed to climate change in some cases. This prediction is based on the trend of smaller body size of endotherms in warmer climates (Bergmann’s rule) and it implies genetic responses rather than phenotypic flexibility. Alternatively, selection for smaller body size or lower mass could be explained by the starvation-predation hypothesis, where lighter individuals have a higher probability of escaping pursuing predators, such as raptors. Evidence that climate warming is driving patterns of size selection in birds in recent times has been mixed. We inspected data on 40 bird species contributed by bird ringers to the South African Ringing Scheme (SAFRING) for changes in body mass and condition as a function of time (year), minimum temperature of the day of capture, maximum temperature of the previous day, and rainfall data in the south-western Cape Floristic Region (fynbos) around Cape Town, South Africa, for the period 1988–2015.
- Full Text:
- Date Issued: 2020
Detecting Similarity in Multi-procedure Student Programs Using only Static Code Structure
- Authors: Bradshaw, Karen L , Chindeka, Vongai
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/440260 , vital:73761 , ISBN 9783030356286 , https://doi.org/10.1007/978-3-030-35629-3_14
- Description: Plagiarism is prevalent in most undergraduate programming courses, including those where more advanced programming is taught. Typical strategies used to avoid detection include changing variable names and adding empty spaces or comments to the code. Although these changes affect the visual components of the source code, the underlying structure of the code remains the same. This similarity in structure can indicate the presence of plagiarism. A system has been developed to detect the similarity in the structure of student programs. The detection system works in two phases: The first phase parses the source code and creates a syntax tree, representing the syntactical structure of each of the programs, while the second takes as inputs two program syntax trees and applies various comparison algorithms to detect their similarity. The outcome of the comparison allows the system to report a result from one of four similarity categories: identical structure, isomorphic structure, containing many structural similarities, and containing few structural similarities. Empirical tests on small sample programs show that the prototype implementation is effective in detecting plagiarism in source code, although in some cases manual checking is needed to confirm the presence of plagiarism.
- Full Text:
- Date Issued: 2020
Learning how to theorize in doctoral writing: A tool for teaching and learning
- Authors: Wilmot, Kirsten
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/445824 , vital:74435 , ISBN 9781003028215 , https://www.taylorfrancis.com/chapters/edit/10.4324/9781003028215-8/learning-theorize-doctoral-writing-kirstin-wilmot
- Description: Doctoral writing is an elusive research practice. Given their size, individuality and disciplinary complexity, analysing doctoral dissertations is a complex task – one that makes defining exact rules for students to follow difficult, if not impossible. In order to open up access to increasingly diverse students, there is a need to make this tacit writing practice explicit. To do so requires a more detailed understanding of what doctoral writing involves. This chapter illustrates an approach that can provide such an understanding. Drawing on the concept of ‘semantic gravity’ from Legitimation Code Theory (LCT), the chapter focuses on a student’s progression from ‘raw’ data description to fully realized theoretical discussions of data. The findings demonstrate how, through the drafting process, specific movements in writing – notably, from strongly contextualized to more abstract meanings – are developed over time. In showcasing these findings, the chapter reveals how LCT is able to make this aspect of doctoral writing explicit and demonstrable to students and supervisors.
- Full Text:
- Date Issued: 2020
No evidence of genetic structure in a sky island endemic: implications for population persistence under a shrinking thermal niche
- Authors: Oswald, Krista N , Edwards, Shelley , Lee, Alan T K , Cunningham, Susan J , Smit, Ben
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/440558 , vital:73793 , https://www.authorea.com/doi/full/10.22541/au.157901262.24420308
- Description: Mountain habitats physically isolated from one another (“sky islands”) represent a unique system for studying dispersal in seemingly isolated populations. The Cape Fold Belt of southwest South Africa forms a sky island archipelago of high-altitude mountain fynbos of which the Cape Rockjumper Chaetops frenatus is an avian-endemic. Continued contraction of habitat due to increasing temperatures may be causing further isolation of C. frenatus populations beyond their dispersal capacities, resulting in currently declining populations in warmer areas of their habitat. In this study, we sequenced two mitochondrial loci and one nuclear locus of 73 C. frenatus samples from 13 localities representing 8 mountain ranges. We found (1) low overall genetic diversity, (2) no evidence for geographically-based genetic structuring, and (3) no evidence for inbreeding within localities. While this may indicate birds are effectively dispersing, it may also indicate strong selective pressure is being placed on their specific genotype. Haplotype networks suggested that C. frenatus may have experienced a bottleneck or founder effect in their recent genetic past —- a result supported by a significantly negative Tajima’s D value. As the first avian genetic study to arise from a range-restricted species of the Cape Fold Belt sky islands, our results show no evidence that C. frenatus are unable to disperse across inhospitable lowland habitat, and thus may not experience isolation due to climate change. We thus potentially found further support that selective pressure in species with highly specialized habitat niches may have a stronger effect than dispersal limitations.
- Full Text:
- Date Issued: 2020
Occurrence of Indo-Pacific bottlenose dolphins (Tursiops aduncus) off the Wild Coast of South Africa using photographic identification:
- Authors: Caputo, Michelle , Bouveroux, Thibaut , Froneman, P William , Shaanika, Titus , Plön, Stephanie
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/160367 , vital:40439 , https://0-doi.org.wam.seals.ac.za/10.1111/mms.12740
- Description: The present study represents the first reported boat‐based photographic identification study of Indo‐Pacific bottlenose dolphins (Tursiops aduncus) off the Wild Coast of southeast South Africa. This area is known for the annual sardine run, which attracts apex predators to the region during the austral winter. Dedicated photo‐identification surveys were conducted along this coast at three different study sites in February, June, and November of each year from 2014 to 2016.
- Full Text:
- Date Issued: 2020