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The article presents a study which aims at analyzing the mitochondrial DNA genetic diversity in the Black Harrier Circus maurus, an endemic avian specie of South Africa. As mentioned, the study was conducted by analyzing the DNA collected from samples of various feather quills. According to the results of the study, the phylogeographical structure was not present in these species.

Simple Summary: Succulent Aizoaceae (often called "mesembs" or ice plants) form a dominant component of the Succulent Karoo in southern Africa, constituting one of the most species-rich families within the Greater Cape Floristic Region (GCFR). Despite the diversity and abundance of these plants, the diversity of insects specialized on them has never been surveyed methodically prior to this study. In a three-year study of the galling insects associated with succulent Aizoaceae in South Africa, we found that they support a rich community of gall midges (Diptera: Cecidomyiidae), virtually all of which are new to science. This is not surprising, given that knowledge of the Afrotropical fauna of gall midges is scarce, with most species described in the 1900s. Here, we describe the new genus Ruschiola with ten species from succulent Aizoaceae in Namaqualand, the Knersvlakte and the Cedarberg regions of South Africa based on morphological, molecular and life history data. The genetic data were particularly important in this study for differentiating taxa, given that Ruschiola species are very similar morphologically. Members of this genus develop in leaf galls or in plant tissues without visible gall formation, and are highly host specific. Aizoaceae (Caryophyllales) constitute one of the major floral components of the unique Greater Cape Floristic Region (GCFR), with more than 1700 species and 70% endemism. Within succulent Aizoaceae, the subfamily Ruschioideae is the most speciose and rapidly diversifying clade, offering potential niches for the diversification of specialized herbivorous insects. Nevertheless, insect diversity on these plants has not been studied to date, and knowledge of gall-inducing insects in the Afrotropics is generally scarce. Our recent observations indicate that succulent Aizoaceae in the GCFR support a rich and largely unstudied community of gall midges (Diptera: Cecidomyiidae). Here, we provide a first report of their diversity with a description of a new genus, Ruschiola Dorchin, and ten new species, based on morphological and molecular analyses of material collected during a three-year targeted survey across major GCFR vegetation types. A high degree of morphological uniformity in Ruschiola suggests recent diversification and necessitated the use of molecular data and laboratory rearing from host plants to verify species boundaries and host ranges. [ABSTRACT FROM AUTHOR]

Dispersal can be motivated by multiple factors including sociality. Dispersal behaviour affects population genetic structure that in turn reinforces social organization. We combined observational information with individual-based genetic data in the Karoo scrub-robin, a facultative cooperatively breeding bird, to understand how social bonds within familial groups affect mating patterns, cause sex asymmetry in dispersal behaviour and ultimately influence the evolution of dispersal. Our results revealed that males and females do not have symmetrical roles in structuring the population. Males are extremely philopatric and tend to delay dispersal until they gain a breeding position within a radius of two territories around the natal site. By contrast, females dispersed over larger distances, as soon as they reach independence. This resulted in male neighbourhoods characterized by high genetic relatedness. The long-distance dispersal strategy of females ensured that Karoo scrub-robins do not pair with relatives thereby compensating for male philopatry caused by cooperation. The observed female-biased strategy seems to be the most prominent mechanism to reduce the risk of inbreeding that characterizes social breeding system. This study demonstrates that tying together ecological data, such as breeding status, determining social relationships with genetic data, such as kinship, provides valuable insights into the proximate causes of dispersal, which are central to any evolutionary interpretation. [ABSTRACT FROM AUTHOR]

Gene flow is traditionally thought to be antagonistic to population differentiation and local adaptation. However, recent studies have demonstrated that local adaptation can proceed provided that selection is greater than the homogenizing effects of gene flow. We extend these initial studies by combining ecology (climate), phenotype (body size), physiological genetics (oxidative phosphorylation genes), and neutral loci (nuclear microsatellites and introns) to test whether selection can counter-balance gene flow and hence promote local adaptation in a bird whose distribution spans an aridity gradient. Our results show that the Karoo scrub-robin's climatic niche is spatially structured, providing the potential for local adaptation to develop. We found remarkably discordant patterns of divergence among mtDNA, morphology, and neutral loci. For the mitochondrial genes, two amino acid replacements, strong population structure and reduced gene flow were associated with the environmental gradient separating western coastal sites from the interior of southern Africa. In contrast, morphology and the neutral loci exhibited variation independent of environmental variables, and revealed extensive levels of gene flow across the aridity gradient, 50 times larger than the estimates for mitochondrial genes. Together, our results suggest that selective pressures on physiology, mediated by the mitochondrial genome, may well be a common mechanism for facilitating local adaptation to new climatic conditions. [ABSTRACT FROM AUTHOR]

Clinus cottoides is a fish endemic to the coast of South Africa, predominantly inhabiting rock pools. All South African clinids are viviparous, but probably breed throughout the year; as such, their dispersal may be limited, unlike species with pelagic larval stages. We analysed 343 fish from 14 localities on the west, south and east coasts using two mitochondrial genes and the second intron of the S7 ribosomal gene. Mitochondrial DNA analyses recovered significant genetic differentiation between fish populations from the east coast and other sampling locations, with a second break found between Gansbaai and Cape Agulhas on the south coast. Nuclear DNA recovered shallower, but significant, levels of population structure. Coalescent analyses suggested remarkably asymmetrical gene flow between sampling locations, suggesting that the cold Atlantic Benguela Current and Indian Ocean Agulhas counter-current play important roles in facilitating dispersal. There was no gene flow between the east coast and the other sites, suggesting that these populations are effectively isolated. Divergence times between them were estimated to at least 68 000 years. Neutrality tests and mismatch distributions suggest recent population expansions, with the exception of peripheral western and eastern populations (possibly a consequence of environmental extremes at the edge of the species distribution). Analyses of the current South African marine protected areas network show that it is not connected and that De Hoop, one of South Africa's largest marine reserves, appears to be an important source population of recruits to both the south and southwest coasts. [ABSTRACT FROM AUTHOR]

The use of DNA sequence data in systematic studies has brought about a revolution in our understanding of avian relationships and when combined with digitized distributional data, has facilitated new interpretations about the origins of diverse clades of the African avifauna including its diversification up through the Tertiary until the present. Here we review recent studies with special reference to Africa’s forest avifauna and specifically comment on the putative origins of ‘hotspots’ of endemism in the Eastern Arc Mountains of Tanzania and in the Cape Region of South Africa. Intriguingly, both these areas appear to have retained populations of relict taxa since the mid-tertiary thermal optimum and at the same time have been centres of recent species differentiation. [ABSTRACT FROM AUTHOR]

Southern Africa is remarkably rich in avian species diversity; however, the evolutionary and biogeographic mechanisms responsible for that diversity are, in general, poorly understood, and this is particularly true with respect to the many species that are endemic or near-endemic to the region. Here, we used mtDNA to assess genetic structure in three southern African bird species to determine whether each was genetically panmictic, or whether there was standing genetic variation upon which abiotic factors (e.g., climate, biome boundaries, geographic features) could have acted to drive lineage diversification. Haplotype diversity was partitioned into two (two species) or three (one species) distinct haplotype clusters that did not reflect biogeographic or biome partitioning; instead, haplotype clusters overlapped in central South Africa. Population and demographic analyses, along with ecological niche modeling and Bayesian Skyline Plots, indicated that each of the three species were likely isolated in refugia during Pleistocene climatic perturbations, with subsequent expansions from refugia resulting in present-day overlapping distributions. Collectively, our analyses suggest that an ephemeral speciation model is operating in southern Africa, driven by the dynamic climatic oscillations that characterize the region. At least some of the regional endemic bird species (e.g., White-eyes, Zosterops spp.) may be the result of sufficiently long periods in refugia as opposed to the distinct but ephemeral clusters recovered within our three focal species. [ABSTRACT FROM AUTHOR]

We describe the isolation of six tetranucleotide microsatellites from the Cape sugarbird ( Promerops cafer) using an enrichment protocol. All loci were highly variable with number of alleles ranging from nine to 26 and values of observed heterozygosity ranging from 0.534 to 0.931. All loci were in Hardy–Weinberg equilibrium with the exception of Pro66 and Pro86. Further analysis of Pro86 indicated it was Z-linked. All loci amplified and were variable in the congeneric Gurneys sugarbird ( Promerops gurneyi). These loci will be used in mating system and phylogeographic studies of Cape sugarbirds in South Africa. [ABSTRACT FROM AUTHOR]

Twenty years after establishing the genus Amblymelanoplia Dombrow, 2002 a large amount of new material collected has warranted a critical review of the established species and a revision of the genus. From this process, we describe 93 new species from the Northern Cape, Western Cape, Mpumalanga and Limpopo Provinces of the Republic of South Africa. A lectotype is designated for Gouna burchelli Arrow, 1917 which is transferred to Amblymelanoplia. The new species are: A. aequabilis Dombrow, new species, A. albolineata Dombrow, new species, A. albosquamosa Dombrow, new species, A. alluaudi Dombrow, new species, A. aquifolia Dombrow, new species, A. arrowi Dombrow, new species, A. atritica Dombrow, new species, A. baehri Dombrow, new species, A. balkei Dombrow, new species, A. bicostata Dombrow, new species, A. bidentata Dombrow, new species, A. bimucronata Dombrow, new species, A. brancuccii Dombrow, new species, A. braunsi Dombrow, new species, A. brinckmanni Dombrow, new species, A. burmeisteri Dombrow, new species, A. caliginosa Dombrow, new species, A. carinata Dombrow, new species, A. castanea Dombrow, new species, A. cederbergensis Dombrow, new species, A. citrusdalensis Dombrow, new species, A. constricta Dombrow, new species, A. costata Dombrow, new species, A. crenata Dombrow, new species, A. deyrollei Dombrow, new species, A. dregei Dombrow, new species, A. drumonti Dombrow, new species, A. elkeae Dombrow, new species, A. enodisuturalis Dombrow, new species, A. fabricii Dombrow, new species, A. felschei Dombrow, new species, A. frischi Dombrow, new species, A. fryi Dombrow, new species, A. fusca Dombrow, new species, A. gifbergensis Dombrow, new species, A. glenlyonensis Dombrow, new species, A. goodhopensis Dombrow, new species, A. gydoensis Dombrow, new species, A. jekeli Dombrow, new species, A. klassi Dombrow, new species, A. kraatzi Dombrow, new species, A. kulzeri Dombrow, new species, A. laingsburgensis Dombrow, new species, A. lichtensteini Dombrow, new species, A. lajoyei Dombrow, new species, A. macrodentata Dombrow, new species, A. mamreensis Dombrow, new species, A. mcleodi Dombrow, new species, A. microdentata Dombrow, new species, A. montana Dombrow, new species, A. mortoni Dombrow, new species, A. multidentata Dombrow, new species, A. murrayi Dombrow, new species, A. nigra Dombrow, new species, A. obscura Dombrow, new species, A. paraunidentata Dombrow, new species, A. pascoei Dombrow, new species, A. pentheri Dombrow, new species, A. pseudocostata Dombrow, new species, A. pseudostrigata Dombrow, new species, A. pseudounidentata Dombrow, new species, A. pulchra Dombrow, new species, A. pulleiacea Dombrow, new species, A. punctata Dombrow, new species, A. pygidialis Dombrow, new species, A. reichei Dombrow, new species, A. robertsi Dombrow, new species, A. sainvali Dombrow, new species, A. scheini Dombrow, new species, A. scutellaris Dombrow, new species, A. selbi Dombrow, new species, A. septentrionalestris Dombrow, new species, A. setosa Dombrow, new species, A. soetwaterensis Dombrow, new species, A. sprecherae Dombrow, new species, A. squamosa Dombrow, new species, A. stalsi Dombrow, new species, A. stellenboschensis Dombrow, new species, A. strigata Dombrow, new species, A. sulcata Dombrow, new species, A. swartbergensis Dombrow, new species, A. swellendamensis Dombrow, new species, A. thomsoni Dombrow, new species, A. tradouwensis Dombrow, new species, A. tuberculata Dombrow, new species, A. turneri Dombrow, new species, A. unidentata Dombrow, new species, A. vansoni Dombrow, new species, A. webbi Dombrow, new species, A. wittmeri Dombrow, new species, A. worcesterensis Dombrow, new species, A. zuercherae Dombrow, new species and A. zumpti Dombrow, new species. Three cryptic species complexes within the species A. burchelli (Arrow, 1917) [+6], A. cornuta Dombrow, 2002 [+10] and A. capensis Dombrow, 2002 [+14] were detected. A revised key of the genus and observations about its biogeography and phylogeny are given. Important details of the morphological characters of the body and the parameres of the species are illustrated and their distributions are mapped. We also provide habitat information.

Advances in understanding the process of species formation require an integrated perspective that includes the evaluation of spatial, ecological and genetic components. One approach is to focus on multiple stages of divergence within the same species. Species that comprise phenotypically different populations segregated in apparently distinct habitats, in which range is presently continuous but was putatively geographically isolated provide an interesting system to study the mechanisms of population divergence. Here, we attempt to elucidate the role of ecology and geography in explaining observed morphological and genetic variation in an understorey-dwelling bird endemic to southeastern Africa, where two subspecies are recognized according to phenotype and habitat affinity. We carried out a range-wide analysis of climatic requirements, morphological and genetic variation across southeast Africa to test the hypothesis that the extent of gene flow among populations of the brown scrub-robin are influenced by their distinct climatic niches. We recovered two distinct trends depending on whether our analyses were hierarchically structured at the subspecies or at the within subspecies level. Between subspecies we found pronounced morphological differentiation associated with strong reproductive isolation (no gene flow) between populations occupying divergent climatic niches characterized by changes in the temperature of the warmest and wettest month. In contrast, within subspecies, we recovered continuous morphological variation with extensive gene flow among populations inhabiting the temperate and sub-tropical forests of southern Africa, despite divergence along the climate axis that is mainly determined by minimum temperature and precipitation of the coldest months. Our results highlight the role of niche divergence as a diversifying force that can promote reproductive isolation in vertebrates.

Studies of both vertebrates and invertebrates have suggested that specialists, as compared to generalists, are likely to suffer more serious declines in response to environmental change. Less is known about the effects of environmental conditions on specialist versus generalist parasites. Here, we study the evolutionary strategies of malaria parasites (Plasmodium spp.) among different bird host communities. We determined the parasite diversity and prevalence of avian malaria in three bird communities in the lowland forests in Cameroon, highland forests in East Africa and fynbos in South Africa. We calculated the host specificity index of parasites to examine the range of hosts parasitized as a function of the habitat and investigated the phylogenetic relationships of parasites. First, using phylogenetic and ancestral reconstruction analyses, we found an evolutionary tendency for generalist malaria parasites to become specialists. The transition rate at which generalists become specialists was nearly four times as great as the rate at which specialists become generalists. We also found more specialist parasites and greater parasite diversity in African lowland rainforests as compared to the more climatically variable habitats of the fynbos and the highland forests. Thus, with environmental changes, we anticipate a change in the distribution of both specialist and generalist parasites with potential impacts on bird communities., (© 2011 Blackwell Publishing Ltd.)