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Quantitative criteria for distinguishing melanic from vertic soil horizons in the central Kruger National Park
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: S.W. Fraser --- Department of Geography, T.H. van Rooyen --- Department of Geography, E. Verster --- Department of Geography,Criteria based on shrink-swell potential, viz. linear shrinkage and COLErod, were used to distinguish between melanic and vertic soil horizons of the Mooiplaas region in central Kruger National Park. For linear shrinkage the proposed boundary value separating melanic and vertic... -
Advances in pedology in South Africa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: P.A.L. le Roux --- Department of Soil, Crop and Climate Sciences, M. Hensley --- Department of Soil, Crop and Climate Sciences, C.W. van Huyssteen --- Department of Soil, Crop and Climate Sciences,The ability of soil to serve as a unique buffer of water, organic carbon, nutrients, pH, redox and temperature is recognised in environmental research. A detailed study on hardpan carbonate and dorbank horizons in the commonly occurring ‘heuweltjies’ of the... -
Sexual size dimorphism in montane cordylid lizards: a case study of the dwarf crag lizard, Pseudocordylus nebulosus
Item type: Journal Article • Journal: African Zoology • Authors: Eloise Costandius --- Department of Botany & Zoology, South Africa P. le Fras N. Mouton --- Department of Botany & Zoology, South AfricaThe aim of this study was to provide information on sexual size dimorphism (SSD) in Pseudocordylus nebulosus and to discuss the observed variation in SSD among montane cordylids. Data for P. nebulosus were recorded in the Landdroskop area in the... -
Faecal analysis suggests generalist diets in three species of Western Cape cordylids
Item type: Journal Article • Journal: African Zoology • Authors: S. Clusella-Trullas --- Department of Botany and Zoology, South Africa A. Botes --- Department of Botany and Zoology, South AfricaClimate has been proposed as an explanation for the present-day distribution of closely-related melanistic and non-melanistic cordylid species in the southwestern Cape of South Africa. However, diet may also contribute towards shaping geographic distributions. We present preliminary data on diet... -
Are melanistic populations of the Karoo girdled lizard, Karusasaurus polyzonus, relics or ecotypes? A molecular investigation
Item type: Journal Article • Journal: African Zoology • Authors: Hanlie M. Engelbrecht --- Department of Botany and Zoology, South Africa P. le Fras N. Mouton --- Department of Botany and Zoology, South Africa Savel R. Daniels --- Department of Botany and Zoology, South AfricaIt has been proposed that melanism in cordylids evolved in response to a single climatic event and that melanistic populations of Karusasaurus polyzonus are relictual. This study investigates the genetic relationships of melanistic and non-melanistic populations of K. polyzonus along... -
Reproductive seasonality of southern African inshore and estuarine invertebrates – a biogeographic review
Item type: Journal Article • Journal: African Zoology • Authors: Alan N. Hodgson --- Department of Zoology and Entomology, South AfricaA literature review reveals that reproductive seasonality of less than 1% of South Africa’s inshore marine invertebrates has been studied. Approximately 95% of studies have been on large, long-lived, gonochoristic, iteroparous species, and nearly 50% on molluscs. There is only... -
The phylogenetic affinities of Trachylepis sulcata nigra and the intraspecific evolution of coastal melanism in the western rock skink
Item type: Journal Article • Journal: African Zoology • Authors: Daniel M. Portik --- Department of Biology, U.S.A. Aaron M. Bauer --- Department of Biology, U.S.A. Todd R. Jackman --- Department of Biology, U.S.A.The phylogenetic affinities of the melanistic subspecies Trachylepis sulcata nigra have never been investigated, and it was unclear if this subspecies represented a locally adapted population or a distinct species. Sequences from the nuclear marker RAG-1 (1149 bp), two novel... -
The abundance of an invasive freshwater snail Tarebia granifera (Lamarck, 1822) in the Nseleni River, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: RW Jones --- Department of Zoology and Entomology, South Africa JM Hill --- Department of Zoology and Entomology, South Africa JA Coetzee --- Department of Botany, South Africa TS Avery --- Department of Biology and Mathematics & Statistics, Canada OLF Weyl --- Centre for Invasion Biology, South Africa MP Hill --- Department of Zoology and Entomology, South AfricaThe invasive freshwater snail Tarebia granifera (Lamarck, 1822) was first reported in South Africa in 1999 and it has become widespread across the country, with some evidence to suggest that it reduces benthic macroinvertebrate biodiversity. The current study aimed to... -
Factors that influence household food security in Hamburg and Melani, Eastern Cape, South Africa
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Thulani Ningi --- , South Africa Amon Taruvinga --- , South Africa Leocadia Zhou --- , South Africa Saul Ngarava --- , South AfricaFood is one of the essential areas of service delivery required for a household’s wellbeing and development. Against this background, the literature suggests a high level of food insecurity among rural households in South Africa. Thus far, this study has... -
Analysis of intraspecific colour variation in the fossorial Coastal Legless Lizard, Microacontias litoralis (Scincidae: Acontiinae)
Item type: Journal Article • Journal: The Journal of the Herpetological Association of Africa • Authors: PhomoloL. Mashinini --- Transvaal Museum, South Africa Neil.J. L. Heideman --- University of the Free State, South Africa P. le FrasN. Mouton --- Stellenbosch University, South AfricaAn analysis of intraspecific variation in the fossorial skink Microacontias litoralis revealed that orange‐coloured and melanistic individuals co‐occur at several localities. Body colour was found to be independent of sex and body size. Both orange‐coloured and melanistic in situ embryos... -
New range extensions for Dasypeltis atra Sternfeld in Tanzania (Serpentes : Colubridae), with a review of the distribution of colour phases
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: DonaldG. Broadley --- Biodiversity Foundation for Africa, Zimbabwe MichaelF. Bates --- National Museum, South AfricaFour Tanzanian specimens of the patterned phase of Dasypeltis atra represent range extensions into savanna areas. One of these specimens, from Ibaya Camp in Mkomazi Game Reserve, extends the species’ range by about 100 km to the south‐east from Mount... -
Testing the thermal melanism hypothesis for Cape Cobras (Naja nivea) using community science photographic data
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: Jody M Barends --- University of Johannesburg, South Africa Kim J Scholtz --- University of the Western Cape, South AfricaAnimal colour is a highly adaptive phenotypic trait that can respond to several selection pressures, including those facilitated by variations in climate. The thermal melanism hypothesis predicts that for ectotherms, selection for darker phenotypes should be highest in cooler areas... -
A review of the reported and future potential ecological impacts of the invasive freshwater snail Tarebia granifera in South Africa.
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: JJ Pearson --- North-West University, South Africa R Gerber --- North-West University, South Africa W Malherbe --- North-West University, South Africa NJ Smit --- North-West University, South Africa L de Necker --- North-West University, South AfricaThe Southeast Asian gastropod Tarebia granifera is an invasive freshwater snail across several continents. Our review summarises the impacts of this invasive snail on invaded aquatic ecosystems. The most important impacts are those related to their ability to reproduce quickly...