Eastern Parts Of Southern Africa Research Articles

Out of the desert: Paleoclimatic changes drove the diversification of arid-adapted Ocymyrmex ants in southern Africa

A highly endemic ant fauna is found in the arid regions of southern Africa, including species in the genus Ocymyrmex. This genus of ants has higher species richness in the western arid regions of southern Africa compared to tropical and subtropical parts of the continent. The processes that have produced these patterns of diversity and distribution of arid adapted ants in southern Africa have never been investigated. The diversification of many other taxa in the region has been associated with past climate fluctuations that occurred during the Miocene epoch. In this study, the nature and timing of historical processes that may have led to the diversification within Ocymyrmex were assessed. We hypothesized that past climate oscillations, characterized by long periods of aridification, have driven the current distribution of Ocymyrmex species that resulted in the highest species richness of the genus in the Deserts & xeric shrublands biome in southern Africa.Ninety-four Ocymyrmex worker specimens from Botswana, Kenya, Namibia, South Africa, Tanzania and Zimbabwe, representing 21 currently described species and six morphospecies, were included in a phylogenomic analysis. Phylogenies for the genus, based on next generation sequencing data from ultraconserved elements, were inferred using Maximum Likelihood, and a dating analysis was performed using secondary age estimates as calibration points. A distribution database of Ocymyrmex records was used to assign species ranges, which were then coded according to major biomes in southern Africa and used as input for biogeographical analysis. We explored the phylogenomic relationships of Ocymyrmex and analysed these within a biogeographical and paleoclimatic framework to disentangle the potential processes responsible for diversification in this group. Dating analyses estimated that the crown age of Ocymyrmex dates to the Oligocene, around 32 Ma. Diversification within this group occurred between the mid-Miocene (∼12.5 Ma) and Pleistocene (∼2 Ma). Our biogeographic analyses suggest that Ocymyrmex species originated in the south-western region of southern Africa, which is now part of the Deserts & xeric shrublands biome and diversified into eastern subtropical areas during the Pliocene. Paleoclimatic changes resulting in increased aridity during the Miocene likely drove the diversification of the genus Ocymyrmex. It is most likely that the diversification of grasslands, because of historical climate change, facilitated the diversification of these ants to the eastern parts of southern Africa when open grasslands replaced forests during the early Miocene.

The taxonomy of Kalanchoe brachyloba Welw. ex Britten (Crassulaceae)

Summary: The taxonomy of Kalanchoe brachyloba Welw. ex Britten, a common species in the western, central, northern, and eastern parts of southern Africa, and further north to central Africa, is reviewed. Although having affinities with K. paniculata Harv., K. brachyloba is a distinctive species characterised by its sessile, arched, oblong-lanceolate leaves that are lengthwise-folded upwards along the midrib, and have a velvety feel to the surface. The leaf margins are coarsely and irregularly serrate-lobed to crenate, rarely entire as in K. paniculata, which has flat to variously floppily folded, subcircular to broadly ovate leaves. K. brachyloba is one of the few southern African species of which the flowers are twisted below the free portions (lobes) of the petals. An amplified description and a distribution map are provided for the species. The name K. brachyloba is lectotypified, and the typification of several of its synonyms is clarified.

Intestinal transport and absorption of bioactive phenolic compounds from a chemically characterized aqueous extract of Athrixia phylicoides

Ethnopharmacological relevanceAthrixia phylicoides, popularly known as “bush tea”, is an indigenous aromatic shrub found in mountainous and grassland areas of the northern and eastern parts of southern Africa. The plant is traditionally used for the treatment of several ailments, including coughing, treating infected wounds, treating boils and sore throat, hypertension and heart disease. Potential anti-diabetic effects have also been demonstrated in vitro. Aim of the studyTo investigate the intestinal transport of prominent phenolic constituents, across a fully differentiated Caco-2 monolayer, using a characterized aqueous extract of A. phylicoides, previously shown to have bioactivity. Materials and methodsHPLC-DAD and LC/MS analyses were used to identify the major phenolic compounds within the extract. Intestinal transport of the phenolic compounds was assessed using a differentiated Caco-2 monolayer model in order to predict bioavailability and identify metabolite formation. Rate of transport, efflux and percentage cross-over were calculated for the respective phenolic compounds. ResultsNine prominent compounds, present in the aqueous extract of A. phylicoides, were identified. Of these, three phenolic acids (protocatechuic acid, caffeic acid and para-coumaric acid), crossed the Caco-2 cell monolayer in significant amounts, with Papp values of 4.52, 4.35 (×10−6cm/s) and 2.38 (×10−5cm/s), respectively. para-Coumaric acid was shown to have the highest predicted bioavailability. ConclusionsPara-Coumaric acid, identified for the first time in A. phylicoides, was shown to have the highest predicted bioavailability suggesting that it could play a major role in the bioactivity of A. phylicoides.

Taxonomic revision of the Afrotropical bee genus Serapista Cockerell (Hymenoptera: Apoidea: Megachilidae: Megachilinae: Anthidiini).

The Sub-Saharan bee genus Serapista Cockerell is revised. It comprises six species. Serapista pernigra Cockerell is restored as a valid species, S. aspernigra Eardley and Griswold, new species, is described from the eastern part of southern Africa and Serapista rhodesiana Mavromoustakis is synonymized with S. pernigra. Descriptions, keys for identification, distributional records and floral associations of the species of Serapista are given.

Model simulations of rainfall over southern Africa and its eastern escarpment

Rainfall simulations over southern and tropical Africa in the form of low-resolution Atmospheric Model Intercomparison Project (AMIP) simulations and higher resolution National Centre for Environmental Prediction (NCEP) reanalysis downscalings are presented and evaluated in this paper. The model used is the conformal-cubic atmospheric model (CCAM), a variable-resolution global atmospheric model. The simulations are evaluated with regards to rainfall totals, spatial distribution, seasonality and inter-annual variability. Since both Global Circulation Models (GCMs) and Regional Climate Models (RCMs) are known to have relatively large biases and shortcomings in simulating rainfall over the steep eastern escarpment of southern Africa and in particular Lesotho, the paper has a focus on evaluating model performance over these regions. It is shown that in the reanalysis simulations the model realistically represents the seasonal cycle in rainfall. However, the AMIP simulations are prone to the model overestimating rainfall totals in spring. The spatial distribution of rainfall is simulated realistically; however rainfall totals are significantly overestimated over the escarpment areas of both southern Africa and East Africa. When nudged within the observed circulation patterns of the reanalysis data, the model is capable of realistically simulating inter-annual rainfall variability over the eastern parts of southern Africa.

Predicted Regional and National Distribution ofBactrocera dorsalis(syn.B. invadens) (Diptera: Tephritidae) in Southern Africa and Implications for Its Management

Since its detection in Kenya in 2003, the exotic fruit fly, Bactrocera dorsalis, has rapidly spread throughout sub-Saharan Africa. This study was conducted to predict the potential distribution of B. dorsalis in the southern African region using suitable environmental variables and some feral host plants. Presence data from surveillance information carried out in Mozambique and Swaziland up to 2013 were used for niche modelling to predict the potential geographical distribution of the pest in the southern African region. Prediction for its national distribution within Swaziland was also carried out using distribution data for eight feral host plants. Although variable between countries, predicted habitat suitability for the pest was potentially greater in the eastern parts of southern Africa, with response curves suggesting higher probability of the pest's occurrence in low altitude areas with moderate diurnal temperature and high precipitation during the wettest month of the year. Of the host plants considered, the pest's distribution was associated mainly with Ficus sycomorus. The model's prediction also suggested that human-associated activities, such as irrigation, could influence the distribution and establishment of the pest even in areas of low host-plant richness. Since the presence of B. dorsalis causes restrictions in international trade of its host plants, it is imperative that countries within the region continue surveillance programmes and coordinated strategies to reduce the impact of the pest.

Characterizing the Late Pleistocene MSA Lithic Technology of Sibudu, KwaZulu-Natal, South Africa.

Studies of the African Middle Stone Age (MSA) have become central for defining the cultural adaptations that accompanied the evolution of modern humans. While much of recent research in South Africa has focused on the Still Bay and Howiesons Poort (HP), periods following these technocomplexes were often neglected. Here we examine lithic assemblages from Sibudu that post-date the HP to further the understanding of MSA cultural variability during the Late Pleistocene. Sibudu preserves an exceptionally thick, rich, and high-resolution archaeological sequence that dates to ∼58 ka, which has recently been proposed as type assemblage for the “Sibudan”. This study presents a detailed analysis of the six uppermost lithic assemblages from these deposits (BM-BSP) that we excavated from 2011–2013. We define the key elements of the lithic technology and compare our findings to other assemblages post-dating the HP. The six lithic assemblages provide a distinct and robust cultural signal, closely resembling each other in various technological, techno-functional, techno-economic, and typological characteristics. These results refute assertions that modern humans living after the HP possessed an unstructured and unsophisticated MSA lithic technology. While we observed several parallels with other contemporaneous MSA sites, particularly in the eastern part of southern Africa, the lithic assemblages at Sibudu demonstrate a distinct and so far unique combination of techno-typological traits. Our findings support the use of the Sibudan to help structuring this part of the southern African MSA and emphasize the need for further research to identify the spatial and temporal extent of this proposed cultural unit.

Using potential distributions to explore environmental correlates of bat species richness in southern Africa: Effects of model selection and taxonomy

Abstract We tested the prediction that at coarse spatial scales, variables associated with climate, energy, and productivity hypotheses should be better predictor(s) of bat species richness than those associated with environmental heterogeneity. Distribution ranges of 64 bat species were estimated with niche-based models informed by 3629 verified museum specimens. The influence of environmental correlates on bat richness was assessed using ordinary least squares regression (OLS), simultaneous autoregressive models (SAR), conditional autoregressive models (CAR), spatial eigenvector-based filtering models (SEVM), and Classification and Regression Trees (CART). To test the assumption of stationarity, Geographically Weighted Regression (GWR) was used. Bat species richness was highest in the eastern parts of southern Africa, particularly in central Zimbabwe and along the western border of Mozambique. We found support for the predictions of both the habitat heterogeneity and climate/productivity/energy hypotheses, and as we expected, support varied among bat families and model selection. Richness patterns and predictors of Miniopteridae and Pteropodidae clearly differed from those of other bat families. Altitude range was the only independent variable that was significant in all models and it was most often the best predictor of bat richness. Standard coefficients of SAR and CAR models were similar to those of OLS models, while those of SEVM models differed. Although GWR indicated that the assumption of stationarity was violated, the CART analysis corroborated the findings of the curve-fitting models. Our results identify where additional data on current species ranges, and future conservation action and ecological work are needed.

Breeding Season ofEpomophorus walhbergiin the Lowveld of Swaziland

The fruit bat Epomophorus wahlbergi is abundant in the eastern parts of southern Africa, but its breeding biology remains poorly documented. This study aimed to ascertain the breeding season of this species in northeastern Swaziland where 340 individuals were netted over a 21-month period. Subadults were present throughout the year with two peaks, while lactating females were only present between December and May. These contradictory data are consistent with a bimodal birth peak, and the fact that pregnancy and lactation were both difficult to detect in the field.

An in vitro assessment of the effect of Athrixia phylicoides DC. aqueous extract on glucose metabolism

Athrixia phylicoides DC. is an aromatic shrub indigenous to the eastern parts of Southern Africa. Indigenous communities brew “bush tea” from dried twigs and leaves of A. phylicoides, which is consumed as a beverage and used for its medicinal properties. Plant polyphenols have been shown to be beneficial to Type 2 diabetes mellitus (T2D) and obesity. Aqueous extracts of the plant have been shown to be rich in polyphenols, in particular phenolic acids, which may enhance glucose uptake and metabolism. The aim of this study was to determine the phenolic composition of a hot water A. phylicoides extract and assess its in vitro effect on cellular glucose utilisation. The most abundant phenolic compounds in the extract were 6-hydroxyluteolin-7-O-glucoside, chlorogenic acid, protocatechuic acid, a di-caffeoylquinic acid and a methoxy-flavonol derivative. The extract increased glucose uptake in C2C12, Chang and 3T3-L1 cells, respectively. Intracellular glucose was utilised by both oxidation (C2C12 myocytes and Chang cells; p<0.01 and p<0.05, respectively) and by increased glycogen storage (Chang cells; p<0.05). No cytotoxicity was observed in Chang cells at the concentrations tested. The effects of the extract were not dose-dependent. A. phylicoides aqueous extract stimulated in vitro glucose uptake and metabolism, suggesting that consumption of this phenolic-rich extract could potentially ameliorate metabolic disorders related to obesity and T2D.

Breeding season of Epomophorus walhbergi in the lowveld of Swaziland

The fruit bat Epomophorus wahlbergi is abundant in the eastern parts of southern Africa, but its breeding biology remains poorly documented. This study aimed to ascertain the breeding season of this species in northeastern Swaziland where 340 individuals were netted over a 21-month period. Subadults were present throughout the year with two peaks, while lactating females were only present between December and May. These contradictory data are consistent with a bimodal birth peak, and the fact that pregnancy and lactation were both difficult to detect in the field.

Is commercial Protea farming causing a change in the seasonal range of Gurney's Sugarbird Promerops gurneyi in the KwaZulu-Natal Midlands, South Africa?

Species worldwide are threatened due to various factors including habitat transformation and degradation. The Gurney's Sugarbird Promerops gurneyi is a bird species endemic to southern Africa. It is a nectarivorous species that is highly dependent on Protea woodland areas in the eastern parts of southern Africa and makes seasonal migrations between these localities. Although many of these habitats have been destroyed by human development activities, the start of commercial Protea farms in the KwaZulu-Natal Midlands may provide alternative habitat and year-round food resources for sugarbirds. Presence/absence of Gurney's Sugarbird on seven KwaZulu-Natal Protea farms were recorded monthly for one year (2006–2007) and compared to past distributions from 1980 and 1992. Sugarbirds were found to be resident for the entire year on some farms and breeding. The total distribution of Gurney's Sugarbird has extended with the development of Protea farms, as has its seasonal distribution and its breeding range. Our results also highlight the reliance that sugarbirds have on Protea whether indigenous or exotic species. More research on the interactions between Gurney's Sugarbirds and the commercial Protea farms is needed.

A taxonomic revision of Allocassine N. Robson (Celastraceae)

A taxonomic account is given of the genus Allocassine N. Robson (Cassinoideae, Celastraceae). Allocassine is an isolated monotypic genus remotely related to the other southern African Cassinoideae. A. laurifolia (Harv.) N. Robson is a liana occurring in the eastern parts of southern Africa, Zimbabwe and Mozambique.

Tectonic evolution of the Late Archaean Pongola-Mozaan basin, South Africa

The Pongola-Mozaan basin in the eastern part of southern Africa was subjected to at least one extensional and two regional compressional tectonic events during the Late Archaean. Early NNW-directed thrust and normal faulting events were followed by a major northwest-southeast shortening event. The style and geometry of the deformational structures in the basin were strongly influenced by the pre-existing structure and, in particular, a fault-bounded basement salient along the northwestern margin of the basin.

Prediction of the Summer Rainfall over South Africa

Abstract This study develops methods for the extended-range forecasting of summer rainfall in the eastern part of southern Africa. The predictand is an index (TVR) of the December–January–February precipitation in the Transvaal. The predictors are based on empirical-diagnostic analyses and include the July–August–September values of Tahiti minus Darwin pressure difference as an index (SOI) of the Southern Oscillation; the preceding January–February–March value of the 50-mb zonal wind over Singapore (U50); an index of the October–November surface westerlies along the Indian Ocean equator (UEQ); and an index of November sea surface temperature in the southwestern Indian Ocean (UKT). These predictors serve as input to stepwise multiple regression, linear discriminant analysis, and neural networking. The training period is 1954–78, and the verification period 1979–93. Regression models, using as predictors U50, UEQ, and UKT, account for more than 30% of the variance in the independent dataset. The linear disc...

Early Pottery from the Eastern Part of Southern Africa

Early Pottery from the Eastern Part of Southern Africa

Studies in the genus Lotononis (Crotalarieae, Fabaceae). VIII. A new species of the L. corymbosa group and notes on the taxonomy of the section Lipozygis

The section Lipozygis (E. Mey.) Benth. of Lotononis (DC.) Eckl. & Zeyh. is shown to be an artificial group that should be divided into two distinct and geographically isolated sections. L. pentaphylla (E. Mey.) Benth., L. polycephala (E. Mey.) Benth. and other annuals from the western Cape Province are to be excluded from the section. The remaining species [L. corymbosa (E. Mey.) Benth. and its allies] are all perennial pyrophytes from grassland areas along the eastern parts of southern Africa. A new species of this group, L. difformis B-E. van Wyk, is described. The unusual inflorescence of the new species provides a possible explanation for the evolutionary origin of the inflorescence structure in Lipozygis sensu stricto and related groups. Daar word aangetoon dat die seksie Lipozygis (E. Mey.) Benth. van Lotononis (DC.) Eckl. & Zeyh. ’n kunsmatige groep is wat in twee duidelik onderskeibare en geografies geïsoleerde seksies verdeel behoort te word. L. pentaphylla (E. Mey.) Benth., L. polycephala (E. Mey.) Benth. en ander jaarplante van die westelike Kaapprovinsie sal uitgesluit word van die seksie. Die oorblywende spesies [L. corymbosa (E. Mey.) Benth. en verwante spesies] is almal meerjarige pirofiete van grasveldgebiede langs die oostelike dele van suider-Afrika. ’n Nuwe spesie van hierdie groep, L. difformis B-E. van Wyk, word beskryf. Die ongewone bloeiwyse van die nuwe spesie bied ’n moontlike verklaring vir die evolusionêre ontwikkeling van die bloeiwyse-struktuur in Lipozygis sensu stricto en verwante groepe.

Some Aspects of the Soul-Concept among the Bantu-Speaking Nguni-Tribes of South Africa

The purpose of this paper is to consider some aspects of the fundamental belief system of the Nguni, namely, the worship of the ancestors. Specifically we will be concerned with a few major points; the distinction between the soul and the spirit as the Nguni conceive of it; the difference between family and tribal spirits; the appearance of these spirits to man, and finally the relationship between the living and the dead. This paper pertains to a complex of Bantu-speaking tribes, fairly homogeneous with respect to culture and language, who, with the exception of the Ndebele who moved to the Transvaal little over a century ago, live in the eastern part of southern Africa on the plateau between the Drakensberg escarpment and the Indian Ocean. Generally, they can be divided into three groups, namely the Swazi in the north, the Zulu extending throughout Natal, and the tribes collectively spoken of as the southern Nguni, including the Xhosa, Pondo, Fingo, Ngqika, Baca, Bomvana and others. All of these tribes are historically related, but the passing of four centuries since their division and the influence of neighboring tribal groups, such as the Tonga in the north, Sotho in the west and Khoisan groups in the south have brought about the local linguistic and cultural differences that we observe today. All the Nguni-tribes distinguish clearly in their conception of and their terminology for, the duality in the living person. Each human being has in addition to his physical body (called umzimba by the Zulu), a spiritual counterpart. This takes on the form of the shadow or personality (the Zulu isithunzi) or the breath (the Xhosa umoya), and as an old Xhosa told me, it is this which causes him to lead a good life-in other words it is seen as the conscience. The soul is localized in the chest or heart, or in the head, and according to some is an exact miniature replica of the * This paper was read at the annual Spring Meeting of the American