African Continent (african + continent)

Distribution by Scientific Domains
Distribution within Life Sciences


Selected Abstracts


Corporate Governance in South Africa: a bellwether for the continent?

CORPORATE GOVERNANCE, Issue 5 2006
Melinda Vaughn
The recent onslaught of corporate scandals has compelled the world to acknowledge the profound impact of corporate governance practices on the global economy. Corporate governance is of particular concern in developing economies, where the infusion of international investor capital and foreign aid is essential to economic stability and growth. This paper focuses attention on corporate governance initiatives in South Africa, given its significance as an emerging market, its potential leadership role on the African continent and the country's notable corporate governance reform since the collapse of apartheid in 1994. The evolution of the country's corporate structure and the forces driving corporate governance reform over the past decade will be examined, followed by a review of the most notable reform initiatives in place today. Finally, an assessment of those initiatives will be presented, along with recommendations concerning how South Africa's initiatives can serve as models of enhanced corporate governance standards for the African continent. [source]


Redefining ,Aid' in the China,Africa Context

DEVELOPMENT AND CHANGE, Issue 5 2010
May Tan-Mullins
ABSTRACT Discussions on the politics of Chinese engagement with African development have been marked by increasing concern over Chinese use of aid in exchange for preferential energy deals. Normative liberal discourse criticizes the Chinese for disbursing ,rogue aid' and undermining good governance in the African continent. These criticisms not only ignore the longer-term motivations and modalities of Chinese aid and the historical diversity of Chinese relations with Africa, but also uncritically assume ,Western' aid to be morally ,superior' and ,more effective' in terms of development outcomes. This paper consists of three parts. First, it will discuss the debates surrounding Chinese engagement in Africa, especially around aid and development issues. Second, the paper maps the historical development of China,Africa engagement and investigates the impacts of the changing modalities of Chinese aid with reference to case studies of two countries: Angola and Ghana. It then offers a comparative analysis of the similarities and differences between these two cases. The principal argument is that Chinese and Western donors employ different ideologies and practices of governance to conceal their own interests and political discourses in the African continent. [source]


Diverse alcohol drinking patterns in 20 African countries

ADDICTION, Issue 7 2009
Thomas Clausen
ABSTRACT Aims This paper describes drinking patterns in 20 African countries, exploring the extent of abstention, heavy occasional drinking and daily light drinking and how these aspects of drinking are inter-related. Design and participants Data were collected as part of the World Health Survey in 2002,04 and comprise national representative data sets from 20 African countries. A cross-sectional survey of 77 165 adults aged 18 years and older were undertaken by face-to-face interviews in respondent households. Measures Drinking behaviour was assessed in terms of life-time abstention and the following measures over the 7 days immediately preceding interview: high consumption (15 or more drinks); heavy drinking occasions (five or more standard units at at least one session) and daily light drinking (one or two drinks daily). Findings In four countries (Comoros, Mali, Mauritania and Senegal), virtually all respondents were life-time abstainers. The prevalence of current drinkers (previous week) did not exceed one-third in any country. Among current drinkers the prevalence of heavy drinking varied between 7% and 77% and the prevalence of daily light drinkers varied between 0% and 21%. Overall drinking patterns varied significantly between and within the examined African countries. Conclusions African drinking patterns are diverse, and although life-time abstinence dominates in African countries, a single typical pattern of drinking for the African continent, such as the alleged ,all-or-none' pattern, was not observed. [source]


Pliocene forest dynamics as a primary driver of African bird speciation

GLOBAL ECOLOGY, Issue 1 2010
Gary Voelker
ABSTRACT Aim, Montane tropics are areas of high endemism, and mechanisms driving this endemism have been receiving increasing attention at a global scale. A general trend is that climatic factors do not explain the species richness of species with small to medium-sized geographic ranges, suggesting that geological and evolutionary processes must be considered. On the African continent, several hypotheses including both refugial and geographic uplift models have been advanced to explain avian speciation and diversity in the lowland forest and montane regions of central and eastern Africa; montane regions in particular are recognized as hotspots of vertebrate endemism. Here, we examine the possible role of these models in driving speciation in a clade of African forest robins. Location, Africa. Methods, We constructed the first robustly supported molecular phylogenetic hypothesis of forest robins. On this phylogeny, we reconstructed habitat-based distributions and geographic distributions relative to the Albertine Rift. We also estimated the timing of lineage divergences via a molecular clock. Results, Robust estimates of phylogenetic relationships and clock-based divergences reject Miocene tectonic uplift and Pleistocene forest refugia as primary drivers of speciation in forest robins. Instead, our data suggest that most forest robin speciation took place in the Late Pliocene, from 3.2 to 2.2 Ma. Distributional patterns are complex, with the Albertine Rift region serving as a general east,west break across the group. Montane distributions are inferred to have evolved four times. Main conclusions, Phylogenetic divergence dates coincide with a single period of lowland forest retraction in the late Pliocene, suggesting that most montane speciation resulted from the rapid isolation of populations in montane areas, rather than montane areas themselves being drivers of speciation. This conclusion provides additional evidence that Pliocene climate change was a major driver of speciation in broadly distributed African animal lineages. We further show that lowland forest robins are no older than their montane relatives, suggesting that lowland areas are not museums which house ,ancient' taxa; rather, for forest robins, montane areas should be viewed as living museums of a late Pliocene diversification event. A forest refugial pattern is operating in Africa, but it is not constrained to the Pleistocene. [source]


The Branchiopoda (Crustacea: Anomopoda, Ctenopoda and Cyclestherida) of the rain forests of Cameroon, West Africa: low abundances, few endemics and a boreal,tropical disjunction

JOURNAL OF BIOGEOGRAPHY, Issue 9 2005
George Y. Chiambeng
Abstract Aim, We provide the first in-depth study of the Branchiopoda of the rain forests of Cameroon and also of the African continent. Location, Surface water environments, Cameroon. Methods, Qualitative plankton samples were collected in all types of surface water environments present, ranging from big lakes to water collected in rock crevices or fallen fruit cavities. A tow or hand-held plankton net of mesh size 100 ,m was used, and water volumes filtered were at least several m3 in large water bodies, or half to whole water volume in small water bodies. Results, We recorded 61 species (53 first records for the country), based on 700+ samples collected between September 1998 and March 2002. Anomopoda (92%) was the dominant order, followed by Ctenopoda (6.5%) and Cyclestherida (1.5%). Chydoridae (67%) was the most speciose family followed by Macrothricidae (6.5%) and Daphniidae (5%). Alona (11%) was the dominant genus followed by Chydorus (10%) and Pleuroxus (8%). Several species of Chydorinae, especially of the genus Pleuroxus, are shared with continental Eurasia,North America, but are absent from the Mediterranean and desert,steppe,savanna zones of Africa (boreal,tropical disjunction). Daphnia was absent, as in most tropical lowlands. No single species was really abundant, and a majority were rare to very rare, and of restricted occurrence within the rain forest patches. Comparing Africa, South America and Southeast Asia, we found a current total of 196 species for the combined rain forest areas, out of a world total of 500+ species. Systematic trends in richness at three taxonomic levels were the same for all continents: Anomopoda,Ctenopoda,Cyclestherida at ordinal level, Chydoridae,Daphniidae,Macrothricidae,Sididae at family level and Alona,Chydorus,Macrothrix,Diaphanosoma at genus level. Southeast Asia was richest (111 species, 14 endemics) with South America a close second (110 species, 27 endemics). Africa was the most species-poor (95 species, of which only 5 are endemics). Main conclusions, We hypothesize that the post-Miocene cooling and aridization of the world climate hit the freshwater biota of Africa particularly hard, with more extinction here than elsewhere, and little recolonization. Most extinction occurred in the savanna-desert belt, and eight disjunct boreal species (four Pleuroxus, Picripleuroxus laevis, Kurzia latissima, Alonella exigua, and Monospilus dispar) survive morphologically unchanged since pre-Pleistocene times in the Cameroon rain forest. Slow evolution thus appears typical of these cyclic parthenogenetic branchiopods in which sexual recombination occurs only at intervals. Illustrative of the same slow evolution is the fact that the two endemic cladocerans of Cameroon (Nicsmirnovius camerounensis and Bryospilus africanus) belong to tropicopolitan genera of Gondwanan age. [source]


A new land-cover map of Africa for the year 2000

JOURNAL OF BIOGEOGRAPHY, Issue 6 2004
Philippe Mayaux
Abstract Aim, In the framework of the Global Land Cover 2000 (GLC 2000), a land-cover map of Africa has been produced at a spatial resolution of 1 km using data from four sensors on-board four different Earth observing satellites. Location, The map documents the location and distribution of major vegetation types and non-vegetated land surface formations for the entire African continent plus Madagascar and the other surrounding islands. Methods, The bulk of these data were acquired on a daily basis throughout the year 2000 by the VEGETATION sensor on-board the SPOT-4 satellite. The map of vegetation cover has been produced based upon the spectral response and the temporal profile of the vegetation cover. Digital image processing and geographical information systems techniques were employed, together with local knowledge, high resolution imagery and expert consultation, to compile a cartographic map product. Radar data and thermal sensors were also used for specific land-cover classes. Results, A total of 27 land cover categories are documented, which has more thematic classes than previously published land cover maps of Africa contain. Systematic comparison with existing land cover data and 30-m resolution imagery from Landsat are presented, and the map is also compared with other pan-continental land cover maps. The map and digital data base are freely available for non-commercial uses from http://www.gvm.jrc.it/tem/africa/products.htm Main conclusions, The map improves our state of knowledge of the land-cover of Africa and presents the most spatially detailed view yet published at this scale. This first version of the map should provide an important input for regional stratification and planning purposes for natural resources, biodiversity and climate studies. Résumé Objet, Dans le cadre du projet Global Land Cover 2000 (GLC 2000), une carte d'Afrique d'occupation du sol a été produite à la résolution spatiale de 1 km à partir de données satellitales de 4 capteurs différents. Localisation, La carte représente la distribution des principaux types de végétation et des surfaces non-végétales du continent africain plus Madagascar et les autres îles voisines du continent. Méthodes, La plupart des données fut acquise durant l'année 2000 par le capteur VEGETATION, embarquéà bord du satellite SPOT-4. La réponse spectrale et le profil temporel des formations végétales ont permis la production de la carte d'occupation du sol. Des techniques de traitement d'image et de systèmes d'information géographique ont été combinées à la consultation d'experts locaux et à l'utilisation de cartes nationales et de données à haute résolution spatiale. Des images radar et thermiques ont servi à cartographier des classes spécifiques. Résultats, Un total de 27 classes est cartographié, ce qui est plus que les précédentes cartes basées sur l'imagerie satellitale. Une comparaison systématique avec les cartes publiées et des images Landsat à 30 m est présentée. Les données sont libres d'accès pour un usage non-commercial à l'adresse http://www.gvm.jrc.it/tem/africa/products.htm Conclusion, Cette carte accroît notre connaissance de l'occupation du sol de l'Afrique et présente la vue la plus détaillée jamais publiée à cette échelle. La première version de la carte devrait fournir une base importante pour une stratification régionale et pour la planification d'études sur les ressources naturelles, la biodiversité et le climat. [source]


Natural regeneration and population dynamics of the tree Afzelia quanzensis in woodlands in Southern Africa

AFRICAN JOURNAL OF ECOLOGY, Issue 4 2009
Karin Gerhardt
Abstract The logging of tree species of high commercial value is increasing throughout the African continent, yet the ecology of these species is generally poorly known. We studied the regeneration pattern and size class distribution of Afzelia quanzensis populations in northern South Africa over a 5-year period. Recruitment was low as the annual seedling mortality was >65%. Seedlings were located under the canopy and were affected by drought and browsing. The adults were scattered or were in a clump-dispersed pattern, which would result in higher recruitment of offspring near parents. Individuals of 0,10 cm diameter at breast height (DBH) were few, while there were 32 trees ha,1 at >10 cm DBH with an annual mortality of 0.8%. Annual diameter increments varied between 0.06 and 0.28 cm. It appears that the transition from the sapling into the juvenile stage could be a bottleneck in the regeneration of the species. A longer study, including more rainfall cycles, may reveal other patterns as dry and wet years have different impacts on dynamics. Résumé La coupe d'espèces d'arbres de grande valeur commerciale augmente dans tout le continent africain, pourtant l'écologie de ces espèces est généralement mal connue. Nous avons étudié le schéma de régénération et la distribution des classes d'âge des populations d'Afzelia quanzensis dans le nord de l'Afrique du Sud pendant cinq ans. Le recrutement était faible car la mortalité annuelle des jeunes plants était de plus de 65%. Les jeunes plans se trouvaient sous la canopée et étaient affectés par la sécheresse et par le broutage des animaux. Les adultes étaient dispersés ou se trouvaient en un schéma en bosquet, qui résulte en un plus fort recrutement de la progéniture près des parents. Les individus de 0,10 cm DBH étaient rares, alors qu'il y avait32 arbres ha,1à >10 cm DBH, avec une mortalité annuelle de 0,8%. L'incrément annuel du diamètre variait entre 0,06 et 0,28 cm. Il semble que la transition entre le stade de jeune arbre et celui de juvénile pourrait bien constituer un étranglement dans la régénération de l'espèce. Une étude plus longue, comprenant plus de cycles de pluies, pourrait révéler un autre schéma étant donné que les années sèches et humides ont des impacts différents sur cette dynamique. [source]


Antimalarial drug quality in Africa

JOURNAL OF CLINICAL PHARMACY & THERAPEUTICS, Issue 5 2007
A. A. Amin PhD
Abstract Background and objective: There are several reports of sub-standard and counterfeit antimalarial drugs circulating in the markets of developing countries; we aimed to review the literature for the African continent. Methods: A search was conducted in PubMed in English using the medical subject headings (MeSH) terms: ,Antimalarials/analysis'[MeSH] OR ,Antimalarials/standards'[MeSH] AND ,Africa'[MeSH]' to include articles published up to and including 26 February 2007. Data were augmented with reports on the quality of antimalarial drugs in Africa obtained from colleagues in the World Health Organization. We summarized the data under the following themes: content and dissolution; relative bioavailability of antimalarial products; antimalarial stability and shelf life; general tests on pharmaceutical dosage forms; and the presence of degradation or unidentifiable impurities in formulations. Results and discussion: The search yielded 21 relevant peer-reviewed articles and three reports on the quality of antimalarial drugs in Africa. The literature was varied in the quality and breadth of data presented, with most bioavailability studies poorly designed and executed. The review highlights the common finding in drug quality studies that (i) most antimalarial products pass the basic tests for pharmaceutical dosage forms, such as the uniformity of weight for tablets, (ii) most antimalarial drugs pass the content test and (iii) in vitro product dissolution is the main problem area where most drugs fail to meet required pharmacopoeial specifications, especially with regard to sulfadoxine,pyrimethamine products. In addition, there are worryingly high quality failure rates for artemisinin monotherapies such as dihydroartemisinin (DHA); for instance all five DHA sampled products in one study in Nairobi, Kenya, were reported to have failed the requisite tests. Conclusions: There is an urgent need to strengthen pharmaceutical management systems such as post-marketing surveillance and the broader health systems in Africa to ensure populations in the continent have access to antimalarial drugs that are safe, of the highest quality standards and that retain their integrity throughout the distribution chain through adequate enforcement of existing legislation and enactment of new ones if necessary, and provision of the necessary resources for drug quality assurance. [source]


The Upper Pleistocene to Holocene sediments on the Mediterranean island of Lampedusa (Italy)

JOURNAL OF QUATERNARY SCIENCE, Issue 6 2004
C. Giraudi
Abstract The island of Lampedusa lies on the northern edge of the African continental shelf, but during some Quaternary marine lowstands it was joined to the African continent. The study and dating of the aeolian, alluvial, detrital sediments, calcareous crusts and speleothems have established that the climatic,environmental variations recorded on the island can be related chronologically to those known for northern Libya, Tunisia and the Italian peninsula. During the Last Glacial Maximum, phases of Saharan dust accumulation on Lampedusa occurred, and were coeval with dust accumulation in crater lakes and on high mountains in central-southern Italy, and with phases of glacial advance in the Apennines and in the Alps. During the late Holocene, accumulation of Saharan dust on Lampedusa occurred but there was little accumulation of dust on the northern side of the Mediterranean Sea. With the new data from Lampedusa, it is possible to envisage two different scenarios of atmospheric circulation relating to the Last Glacial Maximum and to the late Holocene. During the Last Glacial Maximum, southerly atmospheric circulation brought rainfall to the southern slopes of the Alps and to the Apennines. During the late Holocene, a prevalent westerly atmospheric circulation became established in the northern Mediterranean. Copyright © 2004 John Wiley & Sons, Ltd. [source]


REGIONAL INCOME EVOLUTION IN SOUTH AFRICA AFTER APARTHEID,

JOURNAL OF REGIONAL SCIENCE, Issue 3 2008
Maarten Bosker
ABSTRACT South Africa is one of the wealthiest countries on the African continent. The high national level (and growth) of GDP per capita, however, masks significant differences in economic performance across South Africa's regions. This paper uses (spatial) Markov chain techniques to describe the evolution of the entire cross-section regional income distribution in terms of its intra-distributional characteristics during the post-Apartheid period. The results indicate a heavily diverging regional income distribution. Relatively poor regions are likely to remain poor or become even poorer and the richest regions will maintain their lead in terms of income levels. Explicitly taking account of space furthermore shows that these high-income regions are acting as local growth poles, absorbing economic activity from their immediate surroundings. Location, trade, education, and the variable fortune of the gold mining industry seem to be important determinants of the observed evolution. [source]


Impact of irrigation on malaria in Africa: paddies paradox

MEDICAL AND VETERINARY ENTOMOLOGY, Issue 1 2001
J. N. Ijumba
Summary The high population growth rate of the African continent has led to an increased demand for food and is in danger of outstripping agricultural production. In order to meet this need, many governments have sought ways of improving food production by initiating large-scale irrigation projects, involving reclamation of arid and semi-arid areas for the cultivation of crops. Although crop irrigation promises one solution to alleviating hunger and encourages economic growth, irrigation has often been blamed for aggravating disease in local communities. Malaria is one of the major tropical diseases associated with irrigation schemes, and changes in the transmission pattern of this disease following irrigation development have been a perennial subject of debate. It has often been assumed that high numbers of malaria vector Anopheles mosquitoes (Diptera: Culicidae) resulting from irrigation schemes lead inevitably to increased malaria in local communities. However, recent studies in Africa have revealed a more complex picture. Increased numbers of vectors following irrigation can lead to increased malaria in areas of unstable transmission, where people have little or no immunity to malaria parasites, such as the African highlands and desert fringes. But for most of sub-Saharan Africa, where malaria is stable, the introduction of crop irrigation has little impact on malaria transmission. Indeed, there is growing evidence that for many sites there is less malaria in irrigated communities than surrounding areas. The explanation for this finding is still unresolved but, in some cases at least, can be attributed to displacement of the most endophilic and anthropophilic malaria vector Anopheles funestus Giles by An. arabiensis Patton with lower vectorial capacity, as the latter thrives more than the former in ricefields. Similarly, among members of the An. gambiae complex, some cytotypes of An. gambiae sensu stricto are more vectorial than others. For example, the Mopti form has high vectorial capacity and breeds perennially in irrigated sites, whereas the savanna form is often sympatric but more seasonal. Also we suggest that many communities near irrigation schemes benefit from the greater wealth created by these schemes. Consequently irrigation communities often have greater use of bednets, better access to improved healthcare and receive fewer infective bites compared with those outside such development schemes. Thus, in most cases, irrigation schemes in Africa do not appear to increase malaria risk, except in areas of unstable transmission. However, developers should take the opportunity to improve health-care facilities for local communities when planning irrigation schemes wherever they occur. [source]


Macrogeographic population structuring in the cosmopolitan agricultural pest Bactrocera cucurbitae (Diptera: Tephritidae)

MOLECULAR ECOLOGY, Issue 13 2010
M. VIRGILIO
Abstract The macrogeographic population structure of the agricultural pest Bactrocera cucurbitae (Diptera: Tephritidae) was investigated in order to identify the geographic origin of the species and reconstruct its range expansion. Individuals of B. cucurbitae were collected from 25 worldwide-distributed localities (n = 570) and genotyped at 13 microsatellite loci. The Bayesian clustering reveals that B. cucurbitae can be subdivided into five main groups corresponding to populations from (i) the African continent, (ii) La Réunion, (iii) Central Asia, (iv) East Asia and (v) Hawaii. The proportions of inter-regional assignments and the higher values of genetic diversity in populations from Pakistan, India and Bangladesh suggest that B. cucurbitae originated in Central Asia and expanded its range to East Asia and Hawaii on one hand and to Africa and the islands of the Indian Ocean on the other. A number of outliers (10,19 specimens according to different clustering algorithms) show high levels of admixture (Q > 0.70) with populations from different regions and reveal complex patterns of inter-regional gene flow. Anthropogenic transport is the most plausible promoter of this large-scale dispersal. The introduction of individuals from geographically distant sources did not have a relevant role in the most recent African invasions, which originated from the expansion of local populations. These results could provide a useful background to better evaluate invasion risks and establish priorities for the management of this cosmopolitan agricultural pest. [source]


Parasitoid fig-wasp evolutionary diversification and variation in ecological opportunity

MOLECULAR ECOLOGY, Issue 7 2010
M. J. MCLEISH
Abstract Ecological processes are manifest in the evolution and form of phenotype diversity. The great abundance of parasitoid species has led to speculation whether rates of speciation and extinction are dependent on parasitoid diversity. If these factors are mutually exclusive, species diversity should fluctuate instead of remaining relatively constant over time. It is not known whether radiations constrained by coevolutionary interactions conform to density-dependent diversification processes. Here we test the prediction that parasitoid fig wasp diversification responds to changes in ecological opportunity and density-independent processes. A phylogenetic approach is used to estimate relative divergence times and infer diversification rate changes using ,-statistics. Monte Carlo constant rates tests that accommodate incomplete sampling could not reject constant rates diversification. Parasitoid fig wasp diversification is consistent with a more complex explanation than density-dependent cladogenesis. The results suggest contemporary African parasitoid fig wasp diversity remains a legacy of an ancient ecological opportunity facilitated by fig tree diversification following the breakup of Pan-African forests and evolution of the savanna biome over the last 55 Ma and the more recent aridification of the African continent in the last 5 Ma. These results imply that amplified phenotypic differentiation of specialist insects coevolving with plants is coupled to evolutionarily infrequent changes in ecological opportunity. [source]


Ethics and Foreign Policy: the Antinomies of New Labour's ,Third Way' in Sub-Saharan Africa

POLITICAL STUDIES, Issue 2 2001
Rita Abrahamsen
This article explores how New Labour has attempted to implement its ideas about a ,third way' foreign policy in sub-Saharan Africa. Through an examination of British foreign policy practices, we explore whether New Labour has succeeded in finding a ,third way' between traditional views of socialism and capitalism in Africa. In particular, the article focuses on New Labour's attempts to build peace, prosperity and democracy on the African continent. We conclude that although New Labour's claims to add an ,ethical dimension' to foreign policy have succeeded in giving Britain a higher profile in the international arena, the implementation of such a policy is intrinsically difficult. These difficulties in turn arise from the antinomies embodied in New Labour's policy, or more specifically from the tension between the liberal internationalism of the third way and traditional concerns for the national interest, as well as the contradictions inherent in a commitment to both political and economic liberalism. [source]


Sufism in West Africa

RELIGION COMPASS (ELECTRONIC), Issue 10 2010
Rüdiger Seesemann
Sufism had a decisive influence on the development and spread of Islam in West Africa. Although it has been the subject of a considerable number of academic works, Sufism in West Africa remains understudied and often misunderstood. French and British colonial views of Islam had a lasting impact on the perception of Sufism in Africa, resulting in its depreciation as a kind of "popular" Islam of the ignorant masses. A closer look at eminent West African Sufi leaders and their movements, including the Qadiriyya, the Tijaniyya, and the Muridiyya, reveals that Sufism articulated itself in a variety of ways over the past three centuries, and that it continues to be a formidable spiritual, intellectual, and social force in many countries in the Western parts of the African continent. [source]


Y-specific microsatellites reveal an African subfamily in taurine (Bos taurus) cattle

ANIMAL GENETICS, Issue 3 2010
L. Pérez-Pardal
Summary Five cattle Y-specific microsatellites, totalling six loci, were selected from a set of 44 markers and genotyped on 608 Bos taurus males belonging to 45 cattle populations from Europe and Africa. A total of 38 haplotypes were identified. Haplogroups (Y1 and Y2) previously defined using single nucleotide polymorphisms did not share haplotypes. Nine of the 27 Y2-haplotypes were only present in African cattle. Network and correspondence analyses showed that this African-specific subfamily clustered separately from the main Y2-subfamily and the Y1 haplotypes. Within-breed genetic variability was generally low, with most breeds (78%) showing haplotypes belonging to a single haplogroup. amova analysis showed that partitioning of genetic variation among breeds can be mainly explained by their geographical and haplogroup assignment. Between-breed genetic variability summarized via Principal Component Analysis allowed the identification of three principal components explaining 94.2% of the available information. Projection of principal components on geographical maps illustrated that cattle populations located in mainland Europe, the three European Peninsulas and Mediterranean Africa presented similar genetic variation, whereas those breeds from Atlantic Europe and British Islands (mainly carrying Y1 haplotypes) and those from Sub-Saharan Africa (belonging to Y2-haplogroup) showed genetic variation of a different origin. Our study confirmed the existence of two large Y-chromosome lineages (Y1 and Y2) in taurine cattle. However, Y-specific microsatellites increased analytical resolution and allowed at least two different Y2-haplotypic subfamilies to be distinguished, one of them restricted to the African continent. [source]


Variation in mitochondrial DNA and maternal genetic ancestry of Ethiopian cattle populations

ANIMAL GENETICS, Issue 4 2009
H. Dadi
Summary This study describes complete control region sequences of mitochondrial DNA (mtDNA) from 117 Ethiopian cattle from 10 representative populations, in conjunction with the available cattle sequences in GenBank. In total, 79 polymorphic sites were detected, and these defined 81 different haplotypes. The haplotype and nucleotide diversity of Ethiopian cattle did not vary among the populations studied. All mtDNA sequences from Ethiopian cattle converged into one main maternal lineage (T1) that corresponds to African Bos taurus cattle. According to the results of this study, no zebu mtDNA haplotypes have been found in Ethiopia, where the most extensive hybridization took place on the African continent. [source]


Front and Back Covers, Volume 26, Number 3.

ANTHROPOLOGY TODAY, Issue 3 2010
June 2010
Front cover caption, volume 26 issue 3 Front cover A Greenpeace activist dressed as Justice protests in front of the Japanese embassy in Buenos Aires. She draws attention to the trial of Toru Suzuki and Junichi Sato, two Greenpeace activists seeking to expose corruption in the Japanese whale meat industry, who are being prosecuted in the Japanese courts for theft and trespass, in a trial that has continued since 2008. Back in 1993, Arne Kalland analyzed the notable success of the Western environmental movement, Greenpeace in particular, in mobilizing public opinion against continued whaling in the northern hemisphere. The key to this success, Kalland argued, lay in the environmentalists' construction of the ,superwhale', an imaginary, mythic creation which displayed numerous positive qualities with which people could closely identify. Environmentalist thinking has now become intertwined with the discourse of animal rights, including the claim that whales are special to the extent that they are entitled to legal rights on a somewhat similar basis to human beings. In this image, the script on the dress, the Japanese emblem of the rising sun, the blindfold and the scales of justice unbalanced by Japanese-caught whale meat all work to signify that the Japanese are entirely out of step with such progressive ideas. In this issue, Adrian Peace argues that the conflicting attitudes of Japan and Australia to whales and on the practice of whaling stem from diverging cultural and historical factors , the most basic among which is that, whilst Australians construe whales as awesome mammals, the Japanese perceive them as mere fish. Back cover FOOTBALL IN AFRICA On 11 June 2010, all eyes will turn to Johannesburg, South Africa, for the start of the 19th FIFA World Cup. The month-long tournament is one of the world's biggest sporting events, and this year will involve 32 teams from all over the world, attracting a worldwide audience of over 3 billion people and involving commercial agreements worth more than US $21 billion. Significantly, this is also the first time the competition has been held on the African continent. On the eve of the tournament, Richard Vokes reflects on the history and meaning of ,the beautiful game' in Africa, on the basis of a case study from southwestern Uganda. Football was introduced to Uganda by early European missionaries, and later gained in popularity as a result of the patronage it received from first colonial, and later post-colonial, state enterprises. However, the game's current mass appeal is a more recent phenomenon, due in large part to the media reforms introduced in Uganda after 1986, and the advent of satellite broadcasting technology. Vokes examines the nature of this new fandom, and of the media environments which have generated it. He argues that whilst certain features of the current craze , in particular, its peculiar fascination for specifically English football , can be seen as an outcome of spectatorship, this does not mean that the phenomenon is superficial. On the contrary, the new interest in football in Uganda has frequently produced unexpected, and in some ways quite profound, social effects. In his editorial Keith Hart uses the occasion of the World Cup to reflect on South Africa's significance for the world, as both the most developed African nation and the chief victim of the HIV/AIDS epidemic. [source]


A Case of Mistaken Identity: "China Inc." and Its "Imperialism" in Sub-Saharan Africa

ASIAN POLITICS AND POLICY, Issue 4 2009
Ian Taylor
The emergence of major Chinese economic and political stakes in Africa is arguably the most important process to have emerged on the African continent since the end of the Cold War. China is now Africa's second most important trading partner, behind the United States but ahead of France and the United Kingdom. Relations are a continuation of Sino-African historical ties, propelled by China's desire to obtain new sources of raw materials and energy for its ongoing economic growth and new export markets for China-based producers on the one hand, and African elites' initiatives to find a non-Western option/leverage on the other hand. However, various commentators have misunderstood the nature of this expansion. It is common for observers to talk of either Chinese "colonization" of Africa, or of "China Inc.'s" venture into Africa. Both views are wide of the mark and reflect an ignorance of the dynamics underpinning the developing relationships between Chinese and African actors. [source]


Child Labour: a survey of selected Asian countries

ASIAN-PACIFIC ECONOMIC LITERATURE, Issue 2 2004
Ranjan Ray
While the African continent has the highest child labour force participation rates, Asia contains the largest pool of child workers. The nature, magnitude and decline in child labour vary sharply between Asian countries. East Asia now has little child labour; however, child labour continues to have a significant presence in South Asia and in parts of Southeast Asia. This paper surveys the literature on child labour in selected Asian countries, paying special attention to its causes and consequences. The evidence presented shows that Asian child labour, especially in South and Southeast Asia, has some common features. For example, the bulk of child labour is in the 10,14 years age group. The phenomenon is largely rural, and child domestic labour constitutes a significant share. The participation rate of Asian children in the 15,17 years age group in economic activities, 48.4 per cent, is the highest in the world. There is a significant gender element in Asian child labour with boys outnumbering girls in economically active work, while the reverse is the case with domestic child labour. A focus of the survey is the empirical findings that provide insights into the policy instruments that may be needed in combating this phenomenon. The survey also discusses some of the important international and national initiatives that have been taken to reduce child labour. [source]


Linkage disequilibrium and natural selection for mimicry in the Batesian mimic Hypolimnas misippus (L.) (Lepidoptera: Nymphalidae) in the Afrotropics

BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2010
IAN J. GORDON
On two occasions, on opposite sides of the African continent (Cape Coast, Ghana, and Dar es Salaam, Tanzania), high adult population densities in the polymorphic butterfly Hypolimnas misippus (a presumed mimic of Danaus chrysippus) were followed by linkage disequilibrium in combinations of fore- and hindwing colour patterns. On both occasions, disequilibrium was caused by significant changes in morph frequencies favouring rarer and more mimetic forms. Recaptures were too few for analysis at Dar, although the changes there took place within a single generation and must have been the result of differential survival. Recapture rate data and survival rate estimates at Cape Coast support the hypothesis that selective predation was responsible, as does the observation of synchronous linkage disequilibrium at Dar in the model D. chrysippus, indicating parasitic mimicry. There was clear selection for the perfection of mimicry for forewings at Dar and for hindwings at Cape Coast. Disequilibrium is also reported for two other sites, Legon (Ghana) and Boksburg (South Africa) and, in all four sites, it was associated with an increase in the most mimetic forms. New chemical evidence is presented to support the contention that D. chrysippus is a defended model. Although all the evidence leads to the conclusion that H. misippus is a Batesian mimic of D. chrysippus, many questions remain, particularly with regard to the identity of predators, the episodic nature of selective predation events, and their apparent lack of lasting and significant impact on overall gene frequencies. We conclude that H. misippus presents both challenges and opportunities for studies on mimicry, and we suggest that linkage disequilibrium can be a useful generic indicator for Gestalt predation on polymorphic prey. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 100, 180,194. [source]


Geschichte und Evolution der Lactose(in)toleranz.

BIOLOGIE IN UNSERER ZEIT (BIUZ), Issue 6 2009
Das Erbe der frühen Viehzüchter
Abstract Die Fähigkeit, auch im Erwachsenenalter noch Lactose verarbeiten zu können, basiert auf Punktmutationen in einem dem Lactase-(LPH-)Gen vorgelagerten Sequenzbereich, der Bindestellen für Regulatorproteine enthält. Die Ursache für die weltweit sehr uneinheitliche Verteilung der Lactase-Persistenz liegt in der europäischen Menschheitsgeschichte: Im Verlauf des 8. vorchristlichen Jahrtausends entwickelte sich im Nahen Osten innerhalb einer größtenteils lactoseintoleranten Population eine Tradition der Milchviehzucht und des Milchverzehrs. Durch den starken Selektionsdruck auf die Lactosetoleranz verbreiteten sich die mutierten Allele sehr schnell. Während des 7. Jahrtausends v. Chr. begannen etliche dieser Populationen sukzessiv Europa zu besiedeln. Auch im nordöstlichen Afrika und auf der arabischen Halbinsel entstand eine Milchwirtschaft, die jedoch auf anderen Mutationen basiert. The ability to digest lactose in adulthood is baised on point mutations within an upstream region of the lactase-(LPH-)gene. This region contains multiple binding sites for different transcription factors. The heterogenous distribution of the lactase persistence all over the world originates from the European history of humanity: in the course of the eighth millennium BC among a mainly lactose-intolerant population in the Near East evolved a cultural practice of dairy farming and milk consumption. As a result of the strong and positive selection the mutated alleles spread out rapidly. In the course of the seventh millennium BC many of these populations gradually settled Central Europe. The beginning of dairy farming in the north east of the African continent and on the Arabian Peninsula are based upon different point mutations. [source]


Polyploidy and new chromosome counts in Helichrysum (Asteraceae, Gnaphalieae)

BOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 3 2008
MERCÈ GALBANY-CASALS
Mitotic chromosome numbers are reported for 31 populations representing 28 taxa of Helichrysum. Twelve are new and eight others provide confirmation of a unique previous reference. A new chromosome number, 2n = 42, is reported for H. odoratissimum. Polyploidy is confirmed as the most significant evolutionary trend in chromosome number within the genus. Chromosome data agree with trends observed in phylogenetic studies: a South African and diploid origin of the genus, followed by a radiation and diversification in southern Africa and several migrations towards the north of the African continent, the Mediterranean basin and Asia. Expansion and diversification of the genus have been accompanied by several genome duplications which have led to the acquisition of the tetraploid, hexaploid and octoploid levels, all in several independent events. Both autopolyploidy and allopolyploidy are suggested as probable speciation agents within the genus. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158, 511,521. [source]


Business ethics as academic field in Africa: its current status

BUSINESS ETHICS: A EUROPEAN REVIEW, Issue 4 2000
Belinda Barkhuysen
Reflection on the state of business ethics as academic field in Africa has been largely neglected, partly because there existed no overall picture of what is happening in this field of study. This paper reports the findings of the first comprehensive survey on the state of business ethics as academic field on the African continent. It has both a descriptive and reflective component. In the descriptive part of the paper the research strategy and methodology used to conduct this survey is outlined as well as the difficulties encountered in the research project. Then the findings with regard to how academics perceived the purpose of this field of study, what academic activity there is within this field, where it is being done, and how it is institutionalised are reported. In the reflective part of the paper, the implications of these findings are considered and some directives for the further development of business ethics as academic field are proposed. [source]