A re-evaluation of morphological differences in the Karoo Thrush Turdus smithi–Olive Thrush Turdus olivaceus species complex
- Authors: Wilson, J W , Symes, C T , Brown, M , Bonnevie, Bo T , de Swardt, D H , Hanmer, D
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447680 , vital:74666 , https://doi.org/10.2989/OSTRICH.2009.80.3.7.970
- Description: There is confusion in the literature concerning the taxonomic status of the Turdus smithi—T. olivaceus species complex. Here we attempt to clarify morphological differences within this complex. In addition, we attempt to clarify identification of the respective taxa. Although mean measurements of morphometric features differed significantly between species and subspecies, these features are not useful in separating species or subspecies due to considerable overlap in measurements. Furthermore, there were often larger differences between subspecies of T. olivaceus (particularly the geographically isolated T. o. swynnertoni) than between T. olivaceus and T. smithi. We therefore suggest that further work investigates the elevation of T. o. swynnertoni to full species status. Plumage characteristics proved more useful in separating T. olivaceus and T. smithi in the field, except in regions where the distributions overlap (potential hybridisation zones). We highlight the importance of clarifying the delineation of separate species particularly with respect to bird census data (e.g. Southern African Bird Atlas Project 2) and studies related to these species.
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A tetrapod fauna from within the Devonian Antarctic Circle
- Authors: Gess, Robert W , Ahlberg, Per Erik Ahlberg
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/72690 , vital:30100 , https://doi.org/10.1126/science.aaq1645 , https://www.sciencemag.org/content/360/6393/1120/suppl/DC1
- Description: Until now, all known fossils of tetrapods (limbed vertebrates with digits) and near-tetrapods (such as Elpistostege, Tiktaalik, and Panderichthys) from the Devonian period have come from localities in tropical to subtropical paleolatitudes. Most are from Laurussia, a continent incorporating Europe, Greenland, and North America, with only one body fossil and one footprint locality from Australia representing the southern supercontinent Gondwana. Here we describe two previously unknown tetrapods from the Late Devonian (late Famennian) Gondwana locality of Waterloo Farm in South Africa, then located within the Antarctic Circle, which demonstrate that Devonian tetrapods were not restricted to warm environments and suggest that they may have been global in distribution.
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Apis florea in Jordan: source of the founder population
- Authors: Haddad, N , Fuchs, S , Hepburn, H Randall , Radloff, Sarah E
- Date: 2009
- Language: English
- Type: text , Article
- Identifier: vital:6844 , http://hdl.handle.net/10962/d1011047
- Description: A recent isolated population of Apis florea has been reported from Aqaba in Jordan at the Red Sea, consisting of numerous colonies within a still limited range which apparently is expanding. This region is about 1500 km apart from its next occurrences in Sudan where it had been introduced and first detected in 1985 and about 2000 km apart from its next natural occurrences in Iran and Oman. These bees apparently have been imported by human transport, most likely by ship. This new location thus represents a major jump in the progression of the species still to fill a wide area of possible locations offering adequate living conditions. Here we attempt to track the possible origin of this new population by morphometric methods. This analysis indicated closest relation to A. florea from Oman, thus being the most likely source of this population.
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Augmenting an e-Commerce service for Marginalized Communities: A Rewards Based Marketing Approach
- Authors: Jere, Norbert R , Thinyane, Mamello , Terzoli, Alfredo
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428463 , vital:72513 , https://www.researchgate.net/profile/Alfredo-Terzoli/publication/228968666_Augmenting_an_e-Com-merce_service_for_Marginalized_Communities_A_Rewards_Based_Marketing_Approach/links/09e4151344c1f615f7000000/Augmenting-an-e-Commerce-service-for-Marginalized-Communities-A-Rewards-Based-Marketing-Approach.pdf
- Description: Information and Communication technologies (ICTs) have been widely deployed in developmental programmes and this has lead to the crea-tion of a new field–ICT for development (ICT4D). Many e-Commerce platforms now exist in many rural areas in developing countries. ICT4D allows Small, Medium and Micro Enterprises (SMMEs) in rural areas to increase sales and gain the market share on the global market. Howev-er, many of these ICT4D projects in marginalized areas fail as a result of lacking the required resources to support ICTs. SMMEs in rural areas face problems in marketing their products on the global market. There-fore, ensuring sustainability of such systems in marginalized areas is important. This paper explains an e-Marketing strategy through a re-ward based negotiation application, aimed at improving the existing e-Commerce platform. The e-Commerce platform has been deployed for the Dwesa community. Dwesa is a rural area in the Eastern Cape prov-ince of South Africa.
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Drought, change and resilience in South Africa's arid and semi-arid rangelands
- Authors: Vetter, Susan M
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6557 , http://hdl.handle.net/10962/d1006017
- Description: Droughts can have serious ecological and economic consequences and will pose an increasing challenge to rangeiand users as the global climate is changing. Finding ways to reduce ecological and economic impacts of drought should thus be a major research thrust. Resilience, defined as the amount of perturbation a social or ecological system can absorb without shifting to a qualitatively different state, has emerged as a prominent concept in ecosystem ecology and more recently as a conceptual framework for understanding and managing complex social-ecological systems. This paper discusses the application and relevance of resilience to understanding and managing ecosystem change, and enhancing the capacity of land users to adapt to droughts. Drought can trigger vegetation change and factors such as grazing management can influence the likelihood of such transitions. Drought can cause differential mortality of perennial plants and this could provide an opportunity for rangeland restoration by opening up establishment sites for desirable species. The capacity of land users to cope with drought is influenced by the resilience of their agro-ecosystems, the diversity of livelihood options, access to resources and institutional support. By these criteria, current agricultural development approaches in South Africa, particularly in communal rangelands and areas of land reform, are unlikely to enhance land users' resilience to drought and other perturbations.
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Rhodes University 2009 Graduation Ceremonies Address
- Authors: Badat, Saleem
- Date: 2009
- Language: English
- Type: text
- Identifier: vital:7585 , http://hdl.handle.net/10962/d1006575
- Description: From introduction: To be awarded a degree or diploma from Rhodes University entails dedicated endeavour. When you joined us you were told that at Rhodes learning and education is a partnership, a relationship of mutual commitment to the pursuit of knowledge and understanding, to the development of expertise and skills, and to the embrace of appropriate values and attitudes. Your graduation is testimony that you have fulfilled your side of the partnership. You have displayed the necessary commitment and willingness to learn, to acquire knowledge and to develop expertise. Your achievement, the fruits of many months and years of toil, is,ultimately, your own great accomplishment.
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Simulating crowd phenomena in african markets
- Authors: Tasse, Flora P , Glass, Kevin R , Bangay, Shaun D
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/433285 , vital:72959 , https://doi.org/10.1145/1503454.1503463
- Description: Crowd simulation is an important feature in the computer graphics field. Typical implementations simulate battle scenes, emergency situations, safety issues or add content to virtual environments. The problem stated in this paper falls in the last category. We present a crowd simulation behavioural model which allows us to simulate identified phenomena in popular local African markets such as narrow street flows and crowd formation around street performances. We propose a three-tier architecture model enable to produce intentions, perform path planning and control movement. We demonstrate that this approach produces the desired behaviour associated with crowds in an African market, which includes navigation, flow formation and circle creation.
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The willingness to pay for dusky kob (Argyrosomus japonicus) restocking: using recreational linefishing licence fees to fund stock enhancement in South Africa
- Authors: Palmer, Ryan M , Snowball, Jeanette D
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/71322 , vital:29833 , https://doi.org/10.1093/icesjms/fsp075
- Description: The economic feasibility of stock enhancement of Argyrosomus japonicus in South Africa was investigated using a willingness-to-pay (WTP) survey. The pilot study provides a unique example of the use of the contingent valuation method as a valuation tool for a proposed stock enhancement programme. An increase in the cost of a recreational fishing permit is used as a potential vehicle of payment. The median value of the maximum that fishers were willing to pay for a recreational fishing permit was R155 (South African Rand) for frequent fishers and R100 for non-frequent fishers. Analysis showed that a fee of more than R100 excluded up to 50% of anglers from the fishery, but that a fee of R100 excluded only 28% of recreational anglers and would generate an additional R12 million annually from the sale of recreational fishing permits. The estimated costs of set-up and running of a stock enhancement programme are substantially lower than this, suggesting that stock enhancement may be an economically feasible management option that deserves more investigation. The WTP method itself produces robust results and is likely to be an effective tool in the management of the marine environment.
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