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Background: The molecular clock is an important genetic tool for estimating evolutionary timescales. However, the detection of a time-dependent effect on substitution rate estimates complicates its application. It has been suggested that demographic processes could be the main cause of this confounding effect. In the present study, I propose a new algorithm for estimating the coalescent age of phylogenetically related sequences, taking into account the observed time-dependent effect on the molecular rate detected by others. Results: By applying this method to real human mitochondrial DNA trees with shallow and deep topologies, I obtained significantly older molecular ages for the main events of human evolution than were previously estimated. These ages are in close agreement with the most recent archaeological and paleontological records favoring the emergence of early anatomically modern humans in Africa 315 ± 34 thousand years ago (kya) and the presence of recent modern humans outside of Africa as early as 174 ± 48 thousand years ago. Furthermore, during the implementation process, I demonstrated that in a population with fluctuating sizes, the probability of fixation of a new neutral mutant depends on the effective population size, which is in better accordance with the fact that under the neutral theory of molecular evolution, the fate of a molecular mutation is mainly determined by random drift. Conclusions: I suggest that the demographic history of populations has a more decisive effect than purifying selection and/or mutational saturation on the time-dependent effect observed for the substitution rate, and I propose a new method that corrects for this effect. [ABSTRACT FROM AUTHOR]

The helmeted guinea fowl Numida meleagris belongs to the order Galliformes. Its natural range includes a large part of sub‐Saharan Africa, from Senegal to Eritrea and from Chad to South Africa. Archaeozoological and artistic evidence suggest domestication of this species may have occurred about 2,000 years BP in Mali and Sudan primarily as a food resource, although villagers also benefit from its capacity to give loud alarm calls in case of danger, of its ability to consume parasites such as ticks and to hunt snakes, thus suggesting its domestication may have resulted from a commensal association process. Today, it is still farmed in Africa, mainly as a traditional village poultry, and is also bred more intensively in other countries, mainly France and Italy. The lack of available molecular genetic markers has limited the genetic studies conducted to date on guinea fowl. We present here a first‐generation whole‐genome sequence draft assembly used as a reference for a study by a Pool‐seq approach of wild and domestic populations from Europe and Africa. We show that the domestic populations share a higher genetic similarity between each other than they do to wild populations living in the same geographical area. Several genomic regions showing selection signatures putatively related to domestication or importation to Europe were detected, containing candidate genes, most notably EDNRB2, possibly explaining losses in plumage coloration phenotypes in domesticated populations. [ABSTRACT FROM AUTHOR]

El artículo discurre sobre los homo sapiens, la teoría de evolución del teórico inglés Charles Darwin y la evolución humana. El autor comenta sobre el descubrimiento del fósil australopitecus afarensis se llama Lucy, la arquelogía y la historia en África y Europa.

Western public administration as a discipline and practice has been foisted on Africa. In its evolutionary trajectory, the dominant narratives of public administration tend to assume a totalizing, universalistic, nomothetic posture as they both undermine and ignore other worldviews. In Africa the upshot has been public policy that scarcely responds robustly to the continent's "wicked problems." While the dominant corpus of Western public administration has seemingly evolved over time, its ontological underpinnings, securely strapped to Enlightenment ideals, remain intact. However, the current turn to process in the literature and the search for alternative ontologies offer a philosophical opening for an authentic African public administration. Such a project is validated by several African ontological values. Drawing on the work of some of Africa's leading philosophers, this article shows how these ontological values are critical for crafting a new public administration for Africa. It argues that a new African public administration must interrogate the ontological bases of the dominant public administration narratives in order to gauge their suitability vis-à-vis Africa's worldview while engaging and possibly accommodating the emergent process orientation turn. [ABSTRACT FROM AUTHOR]

Attempts to resist the marginalisation of African indigenous dialects remain inconclusive due to persistent dissensus in Africa. Thus, this paper examines language barrier as the bane of development in Africa. Data were derived from content analysis of relevant documents, while the discourse was anchored on Darwin's Theory of Evolution. It is argued that hegemonies of popular languages in Africa have contributed to underdevelopment of the continent, as indigenous initiatives geared towards development remain largely locked in folklore. Africans lack access to the rich heritage of their indigenous languages as a result of the imposition of lingua francas such as Arabic, English, French, and Portuguese languages. It is recommended that solutions to the underdevelopment of Africa should be derived from useful traditional values embedded in African indigenous languages. Such languages should be rejuvenated and translated to reflect modern reality. Also, all relevant indigenous perspectives to development must be reactivated. [ABSTRACT FROM AUTHOR]

The abundant evidence that Homo sapiens evolved in Africa within the past 200 000 years, and dispersed across the world only within the past 100 000 years, provides us with a strong framework in which to consider the evolution of human diversity. While there is evidence that the human capacity for culture has a deeper history, going beyond the origin of the hominin clade, the tendency for humans to form cultures as part of being distinct communities and populations changed markedly with the evolution of H. sapiens. In this paper, we investigate ‘cultures’ as opposed to ‘culture’, and the question of how and why, compared to biological diversity, human communities and populations are so culturally diverse. We consider the way in which the diversity of human cultures has developed since 100 000 years ago, and how its rate was subject to environmental factors. We argue that the causes of this diversity lie in the distribution of resources and the way in which human communities reproduce over several generations, leading to fissioning of kin groups. We discuss the consequences of boundary formation through culture in their broader ecological and evolutionary contexts. [ABSTRACT FROM AUTHOR]

For most frogs, advertisement calls are essential for reproductive success, conveying information on species identity, male quality, sexual state and location. While the evolutionary divergence of call characters has been examined in a number of species, the relative impacts of genetic drift or natural and sexual selection remain unclear. Insights into the evolutionary trajectory of vocal signals can be gained by examining how advertisement calls vary in a phylogenetic context. Evolution by genetic drift would be supported if more closely related species express more similar songs. Conversely, a poor correlation between evolutionary history and song expression would suggest evolution shaped by natural or sexual selection. Here, we measure seven song characters in 20 described and two undescribed species of African clawed frogs (genera Xenopus and Silurana) and four populations of X. laevis. We identify three call types - click, burst and trill - that can be distinguished by click number, call rate and intensity modulation. A fourth type is biphasic, consisting of two of the above. Call types vary in complexity from the simplest, a click, to the most complex, a biphasic call. Maximum parsimony analysis of variation in call type suggests that the ancestral type was of intermediate complexity. Each call type evolved independently more than once and call type is typically not shared by closely related species. These results indicate that call type is homoplasious and has low phylogenetic signal. We conclude that the evolution of call type is not due to genetic drift, but is under selective pressure. [ABSTRACT FROM AUTHOR]

A strong postzygotic reproductive barrier separates the recently diverged Asian and African cultivated rice species, Oryza sativa and O. glaberrima. Recently a model of genetic incompatibilities between three adjacent loci: S1A, S1 and S1B (called together the S1 regions) interacting epistatically, was postulated to cause the allelic elimination of female gametes in interspecific hybrids. Two candidate factors for the S1 locus (including a putative F-box gene) were proposed, but candidates for S1A and S1B remained undetermined. Here, to better understand the basis of the evolution of regions involved in reproductive isolation, we studied the genic and structural changes accumulated in the S1 regions between orthologous sequences. First, we established an 813 kb genomic sequence in O. glaberrima, covering completely the S1A, S1 and the majority of the S1B regions, and compared it with the orthologous regions of O. sativa. An overall strong structural conservation was observed, with the exception of three isolated regions of disturbed collinearity: (1) a local invasion of transposable elements around a putative F-box gene within S1, (2) the multiple duplication and subsequent divergence of the same F-box gene within S1A, (3) an interspecific chromosomal inversion in S1B, which restricts recombination in our O. sativa×O. glaberrima crosses. Beside these few structural variations, a uniform conservative pattern of coding sequence divergence was found all along the S1 regions. Hence, the S1 regions have undergone no drastic variation in their recent divergence and evolution between O. sativa and O. glaberrima, suggesting that a small accumulation of genic changes, following a Bateson-Dobzhansky-Muller (BDM) model, might be involved in the establishment of the sterility barrier. In this context, genetic incompatibilities involving the duplicated F-box genes as putative candidates, and a possible strengthening step involving the chromosomal inversion might participate to the reproductive barrier between Asian and African rice species. [ABSTRACT FROM AUTHOR]

In the process of proliferation from Africa, communities of Homo sapiens became more and more different in terms of the colour of their eyes and skin, the languages they spoke, the songs they sang, the animals they hunted or domesticated; now a reverse process seems to be slowly taking place. Of course, many differences remain and there is a strongly positive side to that. However, today in the emerging global megapolis, a painful process of assimilation is replacing the earlier process of dissimilation. The East and the West will probably meet somewhere in the middle ground; both not merely bringing their respective values to the evolving global normative synthesis, these values are being modified in this process. Neither exclusively “Eastern authoritarian collectivistic” nor “Western liberal individualistic” responses are adequate when facing contemporary challenges. In a sense, humankind may indeed be in the process of completing a full cycle: from a single community through the proliferation and diversification of communities towards the emergence of a community of communities that should become, in some important respects, more and more similar to each other, i.e., a slow and contradictory process of assimilation is replacing the millenia-long process of dissimilation. [ABSTRACT FROM PUBLISHER]

This article discusses several general problems that are encountered in the field of evolutionary musicology, with particular reference to theories that postulate an evolutionary link between musical and linguistic ability. Before addressing some of the most pressing theoretical problems in the field, the article acknowledges the potentially unique contributions that researchers situated in Africa can make to the discussion of the origins of music, given their unique relation to the rich abundance of African palaeo-anthropological, archaeological and ethnographic data. Some of the issues raised include the definition of the term 'music', the status of music as some sort of communicative medium for the expression of emotion, musical meaning, musical universals and grammars, and the issue of empirical evidence from other disciplines. [ABSTRACT FROM AUTHOR]

We suggest an ethno-biological approach to analyze the cultural and social drivers of hunting activities and assess sustainability in villages near Makokou, northeast Gabon, based on interviews with hunters, participatory mapping of hunting territories, and daily records of offtakes for 1 yr. Hunting in villages of northeast Gabon is practiced for both local consumption and cash income to cover basic family expenses. There appears to be no clear tendency to abandon subsistence hunting for commercial hunting as in other regions of Africa. Cultural and socioeconomic factors explain the temporal and spatial variation in hunting activities. Hunting increases in the dry season during circumcision ceremonies, when it is practiced mainly at > 10 km from villages, and decreases during the rainy season because most hunters are occupied by other economic activities. Degraded forest such as secondary regrowth supplies 20% of the animals killed and the greatest diversity of species at short distances from villages. Mature forest supplies the species with the greatest commercial value, e.g., red river hog (Potamochoerus porcus), and is the preferred source of meat for traditional ceremonies. In the last 15 yr, hunting patterns have changed rapidly, mainly because of the spread of gun hunting, which had serious implications for the nature of offtakes. Our results suggest that there is potential to allow hunting for resistant species such as blue duiker (Cephalophus monticola) and African brush-tailed porcupine (Atherurus africanus). Other species such as red river hog and small diurnal monkeys require more attention. Specific management systems could be discussed in participatory hunting management plans to identify possible solutions to maintain the population levels of the more critical species. [ABSTRACT FROM AUTHOR]

The article discusses the publication of a document that endorses strategies needed to be implemented for the economic progress and prosperity in Africa and for the establishment of better relationship with the European Union. The strategy introduces forward-looking approach to be implemented that includes economic initiatives, political innovations, geographic coherence, and the possibility for more money.

Discusses various aspects related to the evolution of human beings. Reference to a study on the topic by H. Müller-Karpe; Tabular representation of the history of mankind; Information on several species of early human beings that were found two and a half million years ago in Africa.

In this paper we propose that historically generated institutions and persistent pattern of human capital formation condition the emergent systems of innovation in Africa. These factors determine the development path of the region. We advance the notion of dynamic and non-dynamic systems of innovation, the latter describing the African condition. We combine the strands of literature on institutions and their persistence in shaping development with evolutionary theory and systems of innovation. Evidence is presented on the colonial origins of skewed schooling enrolment, at variance with the industrialization objective of modern economies. Employing simple statistical tests, the persistence of initial human capital (school enrolment) reflects in the significant correlation among the three levels of schooling enrolments, and correlation of enrolment in 1970 with per capita income in 2000, a periodicity of some three decades. This outcome is consistent with the literature on countries at early stages of development. Path-dependency is partially proved even though we did not attempt to investigate all variables making up the system of innovation. This is a first tentative attempt to explore long-run development in Africa within the systems of innovation framework. [ABSTRACT FROM AUTHOR]

Discusses several theories of human anthropology concerning the Africa and the rest of the world evolutionary hypothesis. Assessment of the concept of continental divide; Weaknesses of the Multiregional Model; Trellis model of recurrent genetic interchange.

Among the African Murinae (Rodentia, Muridae), the Praomys complex, whose systematics has been studied by different approaches, has raised numerous taxonomic problems. Different taxa, namely Praomys, Mastomys , Myomys and Hylomyscus have been considered either as separate genera or subgenera of Praomys . In order to understand the relationships within the Praomys complex and to test the monophyly of the genus Praomys , a cladistic analysis was conducted, based on morpho-anatomical factors involving different species of Praomys , Mastomys , Myomys and Hylomyscus. The results indicate that the Praomys complex is monophyletic, as are the genera Hylomyscus , Mastomys and Myomys , whereas the genus Praomys appears paraphyletic. Indeed, a group of species including Praomys jacksoni was found to be more closely related to the genera Mastomys and Myomys than to a Praomys tullbergi -group. The biotopes and the distribution areas of the species were mapped on the phylogeny. It appears that the different clades each present a relative ecological cohesion and are arranged according to a gradient from closed to open habitats. From there, an evolutionary scenario is proposed for the emergence of the different clades and species of the genus Praomys sensu stricto. [ABSTRACT FROM AUTHOR]

Cichlid fishes (Perciformes: Teleostei) found in the lakes of Africa have served as model systems for the study of evolution. The enormous number of species (1000 in Lake Malawi alone), the great diversity of trophic adaptations and behaviors, and the extreme rapidity of their divergence (<50,000 y for some faunas) single out these organisms as examples of evolution in progress. Because these fishes are confined to discrete lacustrine environments and their origination is bounded by geological features, these groups provide models with which to study evolution. We review theoretical studies and empirical research on the cichlid faunas of Africa to provide a synthetic overview of current knowledge of the evolutionary processes at work in this group. This view provides the critical information needed to formulate and test hypotheses that may permit discrimination among the diverse theories and models that have been advanced to explain the evolution of these fishes. [ABSTRACT FROM AUTHOR]

Abstract Aim We propose a phylogeny of selected Hyperolius species (Anura: Hyperoliidae), based on mtDNA sequence data and parsimony analysis. This phylogeny was used to interpret the historical biogeography of the genus in Africa. Location Samples were collected throughout the distribution of Hyperolius in Africa. Methods We compiled distributional maps of all species, summarized historical changes in vegetation and climate in Africa since the late Cretaceous, and used these in combination to identify historical factors that may have contributed to speciation in these frogs. A phylogeny for Hyperolius was derived from mtDNA sequence data and interpreted in terms of climatic and vegetation changes in Africa. Main conclusions Lowland rainforest is proposed to have been the ancestral habitat of Hyperolius . The expansion of savannah and reduction of lowland rainforest were identified as important factors in the differentiation of the more basal species. Finally, the development of the Rift Valley system played an important role in the speciation of derived species with relatively limited distributions. [ABSTRACT FROM AUTHOR]

The article focuses on the developments in hominid paleontology in Africa. New studies on the morphology of many specimens with a concomitant better appreciation of the total morphological pattern and of the ranges of variation within populations. The time scale of hominid evolution in East Africa is becoming progressively clearer with new age determinations based upon the potassium-argon method. It is becoming possible to formulate rentative synoptic models of the chronological and phylogenetic relationships between the South and East African fossil hominids and a single pattern of African hominid phylogeny.

Discusses the importance of ecology in the formation of species. How Charles Darwin got his ideas of species; Ecology being neglected in this century's evolutionary science; The ecological speciation model; Attention being given to environmental factors as well as genes; Bursts of speciation as seen in the cichlid fish in Africa's Lake Victoria; Study on marine and stream-dwelling stickleback fish from British Columbia and their genetically distant counterparts in Japan.

The article presents the author's comments on the study "Genes, Tribes, and the African History," by Scott Mac Eachern, which has been published within the issue. The author thinks that the development of greater chronological controls for rates of genetic change is very important. Referring to some of the social and political issues which accompany genetic research in Africa, the author feels the analysis given in the study should be extended.

The article reports on the production of two human genomes produced in Africa. The genomes are created of civil rights activist Desmond Tutu, and Gubi, a Namibian hunter-gatherer. Gubi, who belongs to the Khoisan community, is the first genome from the minority population of Africa and Tutu comes from the Bantu, the majority population in southern Africa. David Comas, a student of human diversity, states that the genomes will help in tracing the evolution and genetic differences in human beings.