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1.
PLoS One ; 15(11): e0242726, 2020.
Article in English | MEDLINE | ID: mdl-33196675

ABSTRACT

[This corrects the article DOI: 10.1371/journal.pone.0226064.].

3.
PLoS One ; 14(12): e0226064, 2019.
Article in English | MEDLINE | ID: mdl-31869373

ABSTRACT

Flight loss has evolved independently in numerous island bird lineages worldwide, and particularly in rails (Rallidae). The Aldabra white-throated rail (Dryolimnas [cuvieri] aldabranus) is the last surviving flightless bird in the western Indian Ocean, and the only living flightless subspecies within Dryolimnas cuvieri, which is otherwise volant across its extant range. Such a difference in flight capacity among populations of a single species is unusual, and could be due to rapid evolution of flight loss, or greater evolutionary divergence than can readily be detected by traditional taxonomic approaches. Here we used genetic and morphological analyses to investigate evolutionary trajectories of living and extinct Dryolimnas cuvieri subspecies. Our data places D. [c.] aldabranus among the most rapid documented avian flight loss cases (within an estimated maximum of 80,000-130,000 years). However, the unusual intraspecific variability in flight capacity within D. cuvieri is best explained by levels of genetic divergence, which exceed those documented between other volant taxa versus flightless close relatives, all of which have full species status. Our results also support consideration of Dryolimnas [cuvieri] aldabranus as sufficiently evolutionary distinct from D. c. cuvieri to warrant management as an evolutionary significant unit. Trait variability among closely related lineages should be considered when assessing conservation status, particularly for traits known to influence vulnerability to extinction (e.g. flightlessness).


Subject(s)
Biological Evolution , Birds/classification , Animals , Birds/genetics , Birds/physiology , Conservation of Natural Resources , DNA/chemistry , DNA/isolation & purification , DNA/metabolism , Flight, Animal , Genetic Variation , Haplotypes , Indian Ocean , Islands , Phylogeny , Sequence Analysis, DNA
4.
Gigascience ; 8(9)2019 09 01.
Article in English | MEDLINE | ID: mdl-31531675

ABSTRACT

BACKGROUND: Penguins (Sphenisciformes) are a remarkable order of flightless wing-propelled diving seabirds distributed widely across the southern hemisphere. They share a volant common ancestor with Procellariiformes close to the Cretaceous-Paleogene boundary (66 million years ago) and subsequently lost the ability to fly but enhanced their diving capabilities. With ∼20 species among 6 genera, penguins range from the tropical Galápagos Islands to the oceanic temperate forests of New Zealand, the rocky coastlines of the sub-Antarctic islands, and the sea ice around Antarctica. To inhabit such diverse and extreme environments, penguins evolved many physiological and morphological adaptations. However, they are also highly sensitive to climate change. Therefore, penguins provide an exciting target system for understanding the evolutionary processes of speciation, adaptation, and demography. Genomic data are an emerging resource for addressing questions about such processes. RESULTS: Here we present a novel dataset of 19 high-coverage genomes that, together with 2 previously published genomes, encompass all extant penguin species. We also present a well-supported phylogeny to clarify the relationships among penguins. In contrast to recent studies, our results demonstrate that the genus Aptenodytes is basal and sister to all other extant penguin genera, providing intriguing new insights into the adaptation of penguins to Antarctica. As such, our dataset provides a novel resource for understanding the evolutionary history of penguins as a clade, as well as the fine-scale relationships of individual penguin lineages. Against this background, we introduce a major consortium of international scientists dedicated to studying these genomes. Moreover, we highlight emerging issues regarding ensuring legal and respectful indigenous consultation, particularly for genomic data originating from New Zealand Taonga species. CONCLUSIONS: We believe that our dataset and project will be important for understanding evolution, increasing cultural heritage and guiding the conservation of this iconic southern hemisphere species assemblage.


Subject(s)
Genome , Spheniscidae/genetics , Animals , Evolution, Molecular , Phylogeny
7.
PLoS One ; 10(3): e0117003, 2015.
Article in English | MEDLINE | ID: mdl-25798604

ABSTRACT

The samango monkey is South Africa's only exclusively forest dwelling primate and represents the southernmost extent of the range of arboreal guenons in Africa. The main threats to South Africa's forests and thus to the samango are linked to increasing land-use pressure and increasing demands for forest resources, resulting in deforestation, degradation and further fragmentation of irreplaceable habitats. The species belongs to the highly polytypic Cercopithecus nictitans group which is sometimes divided into two species C. mitis and C. albogularis. The number of subspecies of C. albogularis is also under debate and is based only on differences in pelage colouration and thus far no genetic research has been undertaken on South African samango monkey populations. In this study we aim to further clarify the number of samango monkey subspecies, as well as their respective distributions in South Africa by combining molecular, morphometric and pelage data. Overall, our study provides the most comprehensive view to date into the taxonomic description of samango monkeys in South Africa. Our data supports the identification of three distinct genetic entities namely; C. a. labiatus, C. a. erythrarchus and C. a. schwarzi and argues for separate conservation management of the distinct genetic entities defined by this study.


Subject(s)
Cercopithecus/classification , Cercopithecus/genetics , DNA, Mitochondrial/genetics , Genetic Speciation , Genetic Variation/genetics , Microsatellite Repeats , Animals , Body Mass Index , Conservation of Natural Resources , Ecosystem , Hair/chemistry , Phylogeny , Population Density , Species Specificity
8.
Ecol Evol ; 5(19): 4389-99, 2015 10.
Article in English | MEDLINE | ID: mdl-26819703

ABSTRACT

Captive management of ex situ populations of endangered species is traditionally based on pedigree information derived from studbook data. However, molecular methods could provide a powerful set of complementary tools to verify studbook records and also contribute to improving the understanding of the genetic status of captive populations. Here, we compare the utility of single nucleotide polymorphisms (SNPs) and microsatellites (MS) and two analytical methods for assigning parentage in ten families of captive African penguins held in South African facilities. We found that SNPs performed better than microsatellites under both analytical frameworks, but a combination of all markers was most informative. A subset of combined SNP (n = 14) and MS loci (n = 10) provided robust assessments of parentage. Captive or supportive breeding programs will play an important role in future African penguin conservation efforts as a source of individuals for reintroduction. Cooperation among these captive facilities is essential to facilitate this process and improve management. This study provided us with a useful set of SNP and MS markers for parentage and relatedness testing among these captive populations. Further assessment of the utility of these markers over multiple (>3) generations and the incorporation of a larger variety of relationships among individuals (e.g., half-siblings or cousins) is strongly suggested.

9.
PLoS One ; 9(2): e86382, 2014.
Article in English | MEDLINE | ID: mdl-24498273

ABSTRACT

Host and pathogen ecology are often closely linked, with evolutionary processes often leading to the development of host specificity traits in some pathogens. Host specificity may range from 'generalist', where pathogens infect any available competent host; to 'specialist', where pathogens repeatedly infect specific host species or families. Avian malaria ecology in the region remains largely unexplored, despite the presence of vulnerable endemic avian species. We analysed the expression of host specificity in avian haemosporidia, by applying a previously developed host specificity index to lineages isolated from wetland passerines in the Western Cape, South Africa. Parasite lineages were isolated using PCR and identified when possible using matching lineages deposited in GenBank and in MalAvi. Parasitic clades were constructed from phylogenetic trees consisting of Plasmodium and Haemoproteus lineages. Isolated lineages matched some strains of Plasmodium relictum, P. elongatum, Haemoproteus sylvae and H. lanii. Plasmodium lineages infected a wide range of hosts from several avian families in a generalist pattern of infection. Plasmodium spp. also exhibited an infection trend according to host abundance rather than host species. By contrast, Haemoproteus lineages were typically restricted to one or two host species or families, and displayed higher host fidelity than Plasmodium spp. The findings confirm that a range of host specificity traits are exhibited by avian haemosporidia in the region. The traits show the potential to not only impact infection prevalence within specific host species, but also to affect patterns of infection at the community level.


Subject(s)
Bird Diseases/parasitology , Haemosporida/physiology , Host Specificity , Passeriformes/parasitology , Animals , Avian Proteins/genetics , Bird Diseases/classification , Bird Diseases/genetics , Cytochromes c/genetics , Geography , Haemosporida/classification , Haemosporida/genetics , Passeriformes/classification , Passeriformes/genetics , Phylogeny , Sequence Analysis, DNA , South Africa , Species Specificity , Wetlands
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