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1.
The recent literature on cytogenetic and molecular studies of Anopheles funestus, a major vector of malaria in Africa, is reviewed. Molecular data from West and Central Africa suggest a new species in the group closely allied to Anopheles rivulorum. Cytogenetic and molecular studies of populations from West, Central, East and southern Africa indicate considerable genetic structuring within An. funestus itself, which may well restrict the spread of pyrethroid resistance that has been demonstrated in southern Africa.  相似文献   

2.
This paper examines the evidence for hominids outside East Africa during the Early Pleistocene. Most attention has focused recently on the evidence for or against a late Pliocene dispersal, ca. 1.8 Ma., of hominids out of Africa into Asia and possibly southern Europe. Here, the focus is widened to include North Africa as well as southern Asia and Europe, as well as the evidence in these regions for hominids after their first putative appearance ca. 1.8 Ma. It suggests that overall there is very little evidence for hominids in most of these regions before the Middle Pleistocene. Consequently, it concludes that the colonising capabilities of Homo erectus may have been seriously over-rated, and that even if hominids did occupy parts of North Africa, southern Europe and southern Asia shortly after 2 Ma, there is little evidence of colonisation. Whilst further fieldwork will doubtless slowly fill many gaps in a poorly documented Lower Pleistocene hominid record, it appears premature to conclude that the appearance of hominids in North Africa, Europe and Asia was automatically followed by permanent settlement. Rather, current data are more consistent with the view that Lower Pleistocene hominid populations outside East Africa were often spatially and temporally discontinuous, that hominid expansion was strongly constrained by latitude, and that occupation of temperate latitudes north of latitude 40 degrees was largely confined to interglacial periods.  相似文献   

3.
In contrast to mammals, little is known about the phylogeographic structuring of widely distributed African reptile species. With the present study, we contribute data for the leopard tortoise (Stigmochelys pardalis). It ranges from the Horn of Africa southward to South Africa and westwards to southern Angola. However, its natural occurrence is disputed for some southern regions. To clarify the situation, we used mtDNA sequences and 14 microsatellite loci from 204 individuals mainly from southern Africa. Our results retrieved five mitochondrial clades; one in the south and two in the north‐west and north‐east of southern Africa, respectively, plus two distributed further north. Using microsatellites, the southern clade matched with a well‐defined southern nuclear cluster, whilst the two northern clades from southern Africa corresponded to another nuclear cluster with three subclusters. One subcluster had a western and central distribution, another occurred mostly in the north‐east, and the third in a small eastern region (Maputaland), which forms part of a biodiversity hotspot. Genetic diversity was low in the south and high in the north of our study region, particularly in the north‐east. Our results refuted that translocations influenced the genetic structure of leopard tortoises substantially. We propose that Pleistocene climatic fluctuations caused leopard tortoises to retract to distinct refugia in southern and northern regions and ascribe the high genetic diversity in the north of southern Africa to genetic structuring caused by the survival in three refuges and subsequent admixture, whereas tortoises in the south seem to have survived in only one continuous coastal refuge.  相似文献   

4.
《L'Anthropologie》2019,123(1):180-188
African rituals and beliefs have been recorded by various observers (travelers and anthropologists) in different areas in southern Africa within the last two centuries, and these are useful for interpreting prehistoric rock art (paintings and engravings). Notably, Lichtenstein (1812) recorded rituals among Nguni (who interacted with San) in South Africa, where a hunter took on the form of an animal which was symbolically wounded and which was symbolically killed in the belief that this would contribute to success in a forthcoming hunt. In Namibia, Lebzelter (1934) recorded another ritual in which a San hunter symbolically wounded and symbolically killed an animal represented in a drawing. Such rituals relate to the principle of sympathetic hunting magic. The ethnological evidence is discussed in relation to prehistoric rock art in different areas of southern Africa (Wonderwerk Cave in South Africa, Apollo 11 Cave in Namibia, and Melikane Shelter in Lesotho), and in relation to an important photograph of a ritual presumed to be associated with hunting, recorded at Logageng in the southern Kalahari, South Africa. When taken together with linguistic as well as ethnographic evidence, these sources of information support the view that the so-called trance hypothesis (relating to shamanism) and the principle of sympathetic hunting magic are not mutually exclusive, at least in southern Africa (if not elsewhere).  相似文献   

5.
This study examines geographic and temporal variation in three mammalian taxa co-occurring in eastern and southern Africa. The selected taxa-the spotted hyena (Crocuta crocuta), the plains zebra (Equus burchellii), and the impala (Aepyceros melampus)--are geographically widespread in modern times and are abundant in eastern and southern African Plio-Pleistocene fossil sites. Craniodental measurements of modern conspecifics from known geographic locations are compared using multivariate statistical methods to discern patterns of modern geographic variation within taxa. Modern and fossil samples are statistically compared to assess the nature and extent of inferred shifts in body size, both between modern samples and through time in each region. These results indicate that modern spotted hyenas and plains zebras exhibit mainly size variation between regions, with southern African samples possessing statistically larger craniodental metrics than eastern African samples. Comparison of fossil and modern samples reveals that the fossil assemblages do not show the same pattern of geographic variation. Significant temporal changes are more numerous between fossil and modern eastern African samples, and these changes are not mirrored by similar changes in the southern African samples. The changes experienced by taxa in eastern Africa appear to have been more extreme and wide-ranging than those in southern Africa, a presumed refugium. This result accords well with genetic studies of several large mammal species and paleoenvironmental studies suggesting that eastern African localized environments were more affected by tectonism and volcanism than were those in southern Africa. This study suggests that different evolutionary scenarios may have existed within Africa during the Plio-Pleistocene, but that both regions played unique and complementary roles in the evolution of African hominins and the broader faunal community.  相似文献   

6.
Hamer  M.L.  Brendonck  L. 《Hydrobiologia》1997,359(1-3):1-12
Southern Africa is defined here as Africa south of the Zambezi and Kunene Rivers. Here, annual average rainfall, rainfall season, and effective temperature are climatic factors which influence anostracan distribution. The type of temporary pool also appears to have some effect on distribution. Areas of high species richness are not confined to any particular climatic region and such areas occur in arid, montane and subtropical regions of southern Africa. Forty-six anostracan species have been recorded from the subcontinent and 80% of these are endemic. IUCN Red Data assessment of species revealed that two species can be considered 'Critically Endangered', while a further four are 'Endangered', and three are 'Vulnerable'. Many parts of southern Africa have been inadequately sampled but in South Africa, where the anostracans are relatively well known, temporary pool inhabitants are threatened mainly by agriculture, urbanization, pollution and pesticides. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

7.
Summary The prediction that spinescence in plants increases with aridity, soil fertility and mammalian herbivory was examined at regional and local scales in southern Africa. Spinescence tended to increase with aridity. Within arid areas, vegetation of moist, nutrient-rich habitats was more spinescent than that of the surrounding dry plains. Spinescence in plants of drainage lines and pans in arid southern Africa occurs in a wide range of genera and appears to have been selected by the effect of large mammals which concentrate on these moist patches. It is concluded that spinescence may be selected by breakage as well as herbivory, and that in arid areas moisture may be important in mediating mammalian selection of spinescence.  相似文献   

8.
A phylogenetic hypothesis for the patellid limpets is reconstructed by cladistic analysis of morphological characters from 37 species, representing all but one of the living members of the family. Characters included in the analysis are derived from shell shape and microstructure, headfoot and pallial complex, radula and sperm. The species fall into four clades, providing the basis for a new phylogenetic classification into four monophyletic genera: Helcion (four species; southern Africa), Cymbula (eight species; southern Africa, eastern Atlantic, southern Indian Ocean), Scutellastra (17 species; southern and southwestern Africa, Australia, Indo-West Pacific, Eastern Pacific) and Patella (nine species; northeastern Atlantic and Mediterranean). The analysis suggests sister-group relationships between Helcion and Cymbula, and between Scutellastra and Patella. In combination with present-day patterns of geographical distribution, this phylogenetic hypothesis is used to discuss the historical biogeography of the Patellidae. Scutellastra may have originated in southern Africa and dispersed across the Pacific, or alternatively may be a primitively Tethyan group. Both Helcion and Cymbula appear to have originated in southern Africa, but three Cymbula species have dispersed respectively to northwest Africa, St Helena and the southern Indian Ocean. The patellids of the northeastern Atlantic form a single clade, Patella (including P. pellucida), which may have arrived by northward dispersal of an ancestor from southern Africa, or possibly by vicariance of a widespread ancestral Tethyan distribution. The known fossil record of patellids is too fragmentary to permit choice between these alternatives.  相似文献   

9.
The large daisy tribe Gnaphalieae occurs in extra-tropical habitats worldwide, but is most diverse in southern Africa and in Australia. We explore the age and evolutionary history of the tribe by means of a phylogenetic hypothesis based on Bayesian analysis of plastid and nuclear DNA sequences, maximum likelihood reconstruction of ancestral areas, and relaxed Bayesian dating. Early diversification occurred in southern Africa in the Eocene-Oligocene, resulting in a grade of mostly Cape-centred lineages which subsequently began speciating in the Miocene, consistent with diversification times for many Cape groups. Gnaphalieae from other geographic regions are embedded within a southern African paraphylum, indicating multiple dispersals out of southern Africa since the Oligocene to Miocene which established the tribe in the rest of the world. Colonisation of Australia via direct long-distance trans-oceanic dispersal in the Miocene resulted in the radiation which produced the Australasian gnaphalioid flora. The similarly diverse regional gnaphalioid floras of Australasia and southern Africa thus exhibit very different temporal species accumulation histories. An examination of the timing and direction of trans-Indian Ocean dispersal events in other angiosperms suggests a role for the West Wind Drift in long-distance dispersal eastwards from southern Africa.  相似文献   

10.
The phylogeography of three species of African bovids, the hartebeest (Alcelaphus buselaphus), the topi (Damaliscus lunatus), and the wildebeest (Connochaetes taurinus), is inferred from sequence variation of 345 sequences at the control region (d-loop) of the mtDNA. The three species are closely related (tribe Alcelaphini) and share similar habitat requirements. Moreover, their former distribution extended over Africa, as a probable result of the expansion of open grassland on the continent during the last 2.5 Myr. A combination of population genetics (diversity and structure) and intraspecific phylogeny (tree topology and relative branch length) methods is used to substantiate scenarios of the species history. Population dynamics are inferred from the distribution of sequence pairwise differences within populations. In the three species, there is a significant structuring of the populations, as shown by analysis of molecular variance (AMOVA) pairwise and hierarchical differentiation estimations. In the wildebeest, a pattern of colonization from southern Africa toward east Africa is consistent with the asymmetric topology of the gene tree, showing a paraphyletic position of southern lineages, as well as their relatively longer branch lengths, and is supported by a progressive decline in population nucleotide diversity toward east Africa. The phylogenetic pattern found in the topi and the hartebeest differs from that of the wildebeest: lineages split into monophyletic clades, and no geographical trend is detected in population diversity. We suggest a scenario where these antelopes, previously with wide pan-African distributions, became extinct except in a few refugia. The hartebeest, and probably also the topi, survived in refugia north of the equator, in the east and the west, respectively, as well as one in the south. The southern refugium furthermore seems to have been the only place where the wildebeest has survived.  相似文献   

11.
After several decades of research on the subject, we now know when the first livestock reached southern Africa but the question of how they got there remains a contentious topic. Debate centres on whether they were brought with a large migration of Khoe-speakers who originated from East Africa; or whether the livestock were traded down-the-line among hunter-gatherer communities; or indeed whether there was a long history of diverse small scale population movements in this part of the world, one or more of which ‘infiltrated’ livestock into southern Africa. A new analysis of the distribution of stone toolkits from a sizeable sample of sub-equatorial African Later Stone Age sites, coupled with existing knowledge of the distribution of the earliest livestock remains and ceramics vessels, has allowed us to isolate two separate infiltration events that brought the first livestock into southern Africa just over 2000 years ago; one infiltration was along the Atlantic seaboard and another entered the middle reaches of the Limpopo River Basin. These findings agree well with the latest results of genetic research which together indicate that multiple, small-scale infiltrations probably were responsible for bringing the first livestock into southern Africa.  相似文献   

12.
Recent taxonomic revisions of the freshwater crabs of southern Africa (Angola, Botswana, Lesotho, Mozambique, Namibia, South Africa, Swaziland, Zambia and Zimbabwe) allow accurate depictions of their diversity, distribution patterns and conservation status. The southern African region is home to nineteen species of freshwater crabs all belonging to the genus Potamonautes (family Potamonautidae). These crabs show high levels of species endemism (84%) to the southern African region and to the country of South Africa (74%). The conservation status of each species is assessed using the IUCN (2003) Red List criteria, based on detailed compilations of the majority of known specimens. The results indicate that one species should be considered vulnerable, fifteen species least concern and three species data deficient. The results have been utilized by the IUCN for Red Lists, and may prove useful when developing a conservation strategy for southern Africa’s endemic freshwater crab fauna.  相似文献   

13.
Asteraceae are the largest family in southern Africa. Elucidating its origins and radiation in the region requires well-supported species-level phylogenies of the lineages. This paper presents a phylogenetic framework for subtribe Arctotidinae, which have a southern and eastern African-Australian distribution centered in the winter-rainfall region of South Africa. DNA sequence data from five chloroplast fragments (ndhF, psbA-trnH, rps16, trnS-trnfM, and trnT-trnF) and the nuclear ITS region were analyzed separately and in combination using parsimony and Bayesian methods. The data sets comprised exemplars from 18 ingroup species, representing the five currently accepted genera, and four outgroup species from Gorteriinae. All analyses indicated Arctotis and Haplocarpha are polyphyletic as presently circumscribed. The Australian-endemic Cymbonotus lawsonianus was placed within a strongly supported clade also containing A. arctotoides from South Africa and H. schimperi from eastern Africa. Retention of Dymondia and resurrection of Landtia at generic level are strongly supported. The phylogenetic hypotheses indicate the subtribe might have originated in temperate southern or eastern Africa, or it was ancestrally widespread in southern Africa and has diversified vicariously. The derived placement of C. lawsonianus indicates long-distance dispersal from southern Africa to Australia occurred.  相似文献   

14.
15.
T. B. Oatley 《Ostrich》2013,84(1-2):205-209
Oatley, T.B. 2000. Migrant European swallows Hirundo rustica in southern Africa: a southern perspective. Ostrich 71 (1 & 2): 205–209.

A total of 1 457 recoveries and controls of European Swallows Hirundo rustica in the South African Bird Ringing Unit data bank were analysed to provide an update of the apparent origins and dispersion of migrant European Swallows in southern Africa, to investigate local movements within southern Africa, and to yield an estimate of the age structure of the visiting migrants. Although birds from the former USSR and from Britain and Ireland predominate, over 200 recoveries from 20 other European countries have been recorded. More than half of the swallows migrating to southern Africa are from the central third of the species' breeding range. The dispersion of recoveries of swallows ringed in Britain and Ireland is widespread, with 55% recorded from the Eastern Cape, Free State and KwaZulu-Natal. Controls of southern African-ringed swallows at roosts and recoveries elsewhere in the subcontinent suggest that the daily range of migrant swallows is encompassed within a circle of 100 km diameter, but wide-ranging intra-seasonal movements within South Africa have also been recorded. Conservative estimates of the age of European Swallows at recovery indicate that as many as 14% of migrant swallows ringed in southern Africa may Survive to more than three years of age. It is suggested that the experience of migrants that survive to return to Africa one or more times may permit some flexibility in choice of final destination and that mixing of populations in roosts may result in birds arriving at new destinations.  相似文献   

16.
The Makapansgat Limeworks is a significant Pliocene site both for its sample of 35 hominin fossils as well as its wealth of fossil fauna. The lithological and paleontological successions reveal local environmental changes that are important for understanding the context of hominin evolution in southern Africa. Yet most of the site's fossils were found in dumps left behind by quarry operations, and the paleoecological interpretations rest upon debatable assumptions about the original fossil provenience. We have recently initiated systematic paleoanthropological excavations at Makapansgat to recover well provenanced fossils in order to: 1) assess whether faunal successions are discernable in the Makapansgat sequence; 2) assist environmental interpretations of the site; 3) and potentially recover the oldest hominins in South Africa, roughly coincident with Australopithecus afarensis in East Africa. This paper presents a summary of our current paleoenvironmental research at the Limeworks and preliminary results of ongoing in situ excavations.  相似文献   

17.
The research presented here offers new information on the recent evolution of Khoisan populations of southern Africa through the new study of Holocene skeletons. When combined with subfossil and historical remains, these archeological specimens provide a skeletal record for the last 5000–9000 years of southern African prehistory. Multivariate statistical analyses of cranial measurements were used to determine patterns of morphological variation in the skeletal record with which hypotheses of biocultural evolution were tested. These analyses yielded the following results. First, the traditional distinction between Bushmen and Hottentots holds for recent inland individuals. Second, there is a suggestion of a morphologically distinct San population living on the coast of South Africa. The idea of a “Strandloper” population suggested by early scholars is here revived. The third result is that there is little evidence of complete population succession on the coast of South Africa, suggesting that there were no massive population movements associated with the spread of Hottentot pastoralism throughout southern Africa.  相似文献   

18.
Eriocaulon crassiusculum sp. nov. is described from the Kefa province in southwestern Ethiopia. Illustrations are provided for habit as well as details of flowers (including pollen) and seeds. The new species is most closely related to E. transvaalicum , a widespread species in southern and eastern Africa.  相似文献   

19.
Given high‐level commitments to reducing the rate of biodiversity loss by 2010, there is a pressing need to develop simple and practical indicators to monitor progress. In this context, a biodiversity intactness index (BII) was recently proposed, which provides an overall indicator suitable for policy makers. The index links data on land use with expert assessments of how this impacts the population densities of well‐understood taxonomic groups to estimate current population sizes relative to premodern times. However, when calculated for southern Africa, the resulting BII of 84% suggests a far more positive picture of the state of wild nature than do other large‐scale estimates. Here, we argue that this discrepancy is in part an artefact of the coarseness of the land degradation data used to calculate the BII, and that the overall BII for southern Africa is probably much lower than 84%. In particular, based on two relatively inexpensive, ground‐truthed studies of areas not generally regarded as exceptional in terms of their degradation status, we demonstrate that Scholes and Biggs might have seriously underestimated the extent of land degradation. These differences have substantial bearing on BII scores. Urgent attention should be given to the further development of cost‐effective ground‐truthing methods for quantifying the extent of land degradation in order to provide reliable estimates of biodiversity loss, both in southern Africa and more widely.  相似文献   

20.
The rust mycobiota (Uredinales, Basidiomycota) of southern Africa (Botswana, Namibia, and South Africa) is analysed with regard to species richness, generic composition, and similarities to the rust mycobiotas of the remaining African continent and other regions of the world. Southern Africa is home to about 546 rust species: ca 522 species have been reported from South Africa, 73 from Namibia, and less than ten from Botswana. Thirty-two species were considered to be exotics. Two hundred and twenty-five of the species are restricted to southern Africa, suggesting an endemism rate of ca 44 %. At present, the rust fungus:host ratio is 1:38.5, which is much lower than expected from other regions of the world. This low ratio may partly be due to under-exploration of the area, but the results presented here indicate that a natural paucity of rust fungi on certain, especially species-rich plant taxa centred in southern Africa and possibly environmental factors are more important reasons. The predominant genera are Puccinia and Uromyces accounting for ca 59 % of the rust species. The genera Hemileia, Phakopsora and especially Ravenelia, centred in tropical regions, are well represented and sum up to 8 % of the species. Members of Melampsoraceae and Phragmidiaceae, common in temperate regions of the Northern Hemisphere, are scarce. Most of the other 28 recorded teleomorph genera are only represented by three or less species. In an African context, most species are shared with central and east Africa (almost 16 %). Only a few species are disjunct between southern and West Africa or Madagascar. Ca 10 % of the species are shared only with other parts of the paleotropics, especially the Indian subcontinent. Disjunctions of native species with the New World, Australia/New Zealand, or Europe are rare.  相似文献   

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