60 results on '"Burger, Marius"'
Search Results
52. Comparison between a nature reserve and adjacent communal land in Xeric Succulent Thicket: An...
- Author
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Fabricius, Christo and Burger, Marius
- Subjects
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PLANT diversity conservation , *NATURE reserves - Abstract
Focuses on the survey designed to quantify differences in plant diversity between the nature reserve and the adjacent communal area in the point of view of the Xhosa community in South Africa. Demonstration of the contribution of the local communities to inventory-type information about park and nature reserve; Advantages to the community; Conservation benefits.
- Published
- 1997
53. Distribution of Bradypodion taeniabronchum (Smith 1831) and other dwarf chameleons in the eastern Cape Floristic Region of South Africa
- Author
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Tolley, Krystal and Burger, Marius
- Abstract
The evolutionary relationships and taxonomic status of dwarf chameleons in the eastern Cape Floristic Region is not well understood. Through a combination of field observations and mito-chondrial DNA sequencing (ND2 and 16S), it has become apparent that morphological and genetic evidence are often in conflict. In some instances, species that are morphologically quite different, show close genetic relationships, eg., Bradypodion taeniabronchum and B. ventrale. In other cases there are substantial genetic differences between lineages, with little morphological differentiation. For example, dwarf chameleons from the Kouga and the Baviaanskloof mountains were thought to represent a single undescribed species. However, chameleons from these two mountain ranges show large sequence divergence (6.8% for ND2) that is more than twice the value between B. taeniabronchum and B. ventrale. The evolutionary relationships within this group are reticulate in nature, making taxonomy difficult to resolve. Application of only mitochondrial data to resolve the taxonomy of this group is therefore insufficient, because mitochondrial DNA may only indicate historical isolation of lineages, and if used independently, may not be a good indicator of species definitions. Therefore our next step toward resolving the taxonomy of this group is the inclusion of nuclear DNA markers, in conjunction with a full morphological analysis.
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- 2004
- Full Text
- View/download PDF
54. Re-discovery of Cynisca bifrontalis in Gabon, with additional notes on Monopeltis galeata (Reptilia: Amphisbaenia)
- Author
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Branch, William, Pauwels, Olivier, and Burger, Marius
- Abstract
A small series of amphisbaenians from the Toucan/Rabi region, Ogooue-Maritime Province, south-western Gabon, is reported. It includes five specimens of Cynisca bifrontalis (Boulenger 1906), previously known only from the holotype, and five specimens of Monopeltis galeata (Hallowell 1852). The Toucan/Rabi material represents a range extension of 90 km south-east for both species. Morphological variation in the new material is discussed. Body annuli counts in both species differ from documented ranges, but the possible taxonomic significance of this cannot be assessed until larger series become available. Like congeners with extensively fused head shields, C. bifrontalis displays variability in cephalic scutellation. Pre-cloacal pores in females are represented by small scale depressions, but these lack secretion cores. The species reaches a snout-vent length of only 131 mm and is thus one of the smallest known fossorial reptiles. Cynisca haughi (Mocquard 1904) is poorly diagnosed and its taxonomic status requires further study.
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- 2003
- Full Text
- View/download PDF
55. Cryptic species of sharp-nosed reed frogs in the Hyperolius nasutuscomplex: advertisement call differences
- Author
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Channing, Alan, Moyer, David, and Burger, Marius
- Abstract
The sharp-nosed reed frog is widespread in Africa. Although currently recognized as one species, suggestions have been made that more than one species might exist. We analysed 237 calls of 69 males from 19 localities in the western to southern parts of Africa. Calls fall into three groups, which we recognize as cryptic species. Of eight published sound spectrograms, all can be assigned to one of the three species. We recognize Hyperolius nasutus,distributed from western Africa to the Okavango Delta in Botswana; Hyperolius viridis,from the central highlands of northwestern Zambia to southern Tanzania; and Hyperolius acuticeps>which occurs from the Ivory Coast to the southeastern coast of South Africa. We assign published names to the synonymies of these three species. No call data are available for populations in the Congo basin.
- Published
- 2002
- Full Text
- View/download PDF
56. HERALDING A NEW SYSTEMATIC ACCOUNT OF THE SNAKE GENUS CROTAPHOPELTIS, WITH A SPECIAL FOCUS ON THE WIDE-RANGING C. HOTAMBOEIA (SERPENTES: COLUBRIDAE).
- Author
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Engelbrecht, Hanlie M., Branch, William R., Greenbaum, Eli, Burger, Marius, Conradie, Werner, and Tolley, Krystal A.
- Abstract
Crotaphopeltis is one of Africa's most widespread snake genera. Of the six species, the Herald Snake, C. hotamboeia, has the widest distribution across nearly all Afrotropical biomes, except rainforest and hyper-arid regions. Its extensive range, relative abundance, and presumed high dispersal ability suggest that gene flow may be adequate to prevent species-level diversification between populations. Yet, it is possible that ecological and geographical barriers throughout the heterogeneous landscape of sub-Saharan Africa may have promoted allopatric speciation within C. hotamboeia. In contrast, the habitat discontinuity of specialist conspecifics (e.g., the Afromontane C. tornieri) might have induced allopatric speciation, and thus strong genetic structure is especially expected for the habitat specialists in the genus. Therefore, we assessed phylogenetic species boundaries within four of the six Crotaphopeltis species using five genetic markers (16S, cyt b, ND4, c-mos, and RAG1), coupled with a phylogeographical study of the wide-ranging C. hotamboeia. The species-delimitation approach included genetic barcoding in combination with two coalescent-based methods. Results indicated Crotaphopeltis barotseensis, C. degeni, and C. hotamboeia are valid species, whereas C. tornieri comprised two candidate species. Crotaphopeltis hotamboeia did not show cryptic speciation, although strong phylogeographic structure was detected, which appears to correspond with the spatio-temporal pattern of the African savanna. [ABSTRACT FROM AUTHOR]
- Published
- 2019
57. The South African Frog Atlas Project--latest update.
- Author
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Burger, Marius
- Abstract
Reports on the project for the study of frogs called South African Frog Atlas Project (SAFAP) in South Africa. Operational goals of SAFAP for data collection; Duration of the project; Contact person of the project.
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- 1996
58. FROGS ABD FROGGING IN SOUTHERN AFRICA (Book Review).
- Author
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Burger, Marius
- Abstract
Reviews the book 'Frogs and Frogging in Southern Africa,' by Vincent Carruthers.
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- 2002
59. Exploring rain forest diversification using demographic model testing in the African foam‐nest treefrog Chiromantis rufescens
- Author
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Edem A. Eniang, Adam D. Leaché, Danielle Rivera, Eli Greenbaum, Rayna C. Bell, Daniel M. Portik, Marius Burger, Caleb Ofori-Boateng, Gregory F.M. Jongsma, Matthew K. Fujita, Johannes Penner, Mark-Oliver Rödel, Václav Gvoždík, and 30998360 - Burger, Marius
- Subjects
education.field_of_study ,Species complex ,Rhacophoridae ,Ecology ,biology ,Population size ,Species distribution ,Population ,Allopatric speciation ,biology.organism_classification ,Coalescent theory ,Chiromantis rufescens ,Phylogeography ,Geography ,Biogeography ,West Africa ,education ,Ecology, Evolution, Behavior and Systematics ,Demography ,SNPs - Abstract
AIM: Species with wide distributions spanning the African Guinean and Congolian rain forests are often composed of genetically distinct populations or cryptic species with geographic distributions that mirror the locations of the remaining forest habitats. We used phylogeographic inference and demographic model testing to evaluate diversification models in a widespread rain forest species, the African foam‐nest treefrog Chiromantis rufescens. LOCATION: Guinean and Congolian rain forests, West and Central Africa. TAXON: Chiromantis rufescens. METHODS: We collected mitochondrial DNA (mtDNA) and single‐nucleotide polymorphism (SNP) data for 130 samples of C. rufescens. After estimating population structure and inferring species trees using coalescent methods, we tested demographic models to evaluate alternative population divergence histories that varied with respect to gene flow, population size change and periods of isolation and secondary contact. Species distribution models were used to identify the regions of climatic stability that could have served as forest refugia since the last interglacial. RESULTS: Population structure within C. rufescens resembles the major biogeographic regions of the Guinean and Congolian forests. Coalescent‐based phylogenetic analyses provide strong support for an early divergence between the western Upper Guinean forest and the remaining populations. Demographic inferences support diversification models with gene flow and population size changes even in cases where contemporary populations are currently allopatric, which provides support for forest refugia and barrier models. Species distribution models suggest that forest refugia were available for each of the populations throughout the Pleistocene. MAIN CONCLUSIONS: Considering historical demography is essential for understanding population diversification, especially in complex landscapes such as those found in the Guineo–Congolian forest. Population demographic inferences help connect the patterns of genetic variation to diversification model predictions. The diversification history of C. rufescens was shaped by a variety of processes, including vicariance from river barriers, forest fragmentation and adaptive evolution along environmental gradients.
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- 2019
60. Sexual Dichromatism Drives Diversification Within a Major Radiation of African Amphibians
- Author
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Jimmy A. McGuire, Lucinda P. Lawson, Václav Gvoždík, Werner Conradie, Raffael Ernst, Caleb Ofori-Boateng, Robert C. Drewes, William R. Branch, Timothy J. Colston, Marcel T. Kouete, Michael Veith, Gregory F.M. Jongsma, Annemarie Ohler, Eli Greenbaum, Jos Kielgast, Mark-Oliver Rödel, Aaron M. Bauer, Annika Hillers, Zoltán T. Nagy, David C. Blackburn, Simon P. Loader, Jens V. Vindum, Stefan Lötters, Theodore J. Papenfuss, Ange-Ghislain Zassi-Boulou, Marius Burger, Alan Channing, Mareike Hirschfeld, Christopher D. Barratt, James Harvey, J. Maximilian Dehling, Arie van der Meijden, Susanne Müller, Ulrich Sinsch, Rayna C. Bell, Daniel M. Portik, Michele Menegon, Adam D. Leaché, Daniela C. Rößler, Nelson Mandela Metropolitan University [Port Elizabeth, South Africa], North-West University [Potchefstroom] (NWU), Port Elizabeth Museum, University of Texas [El Paso] (UTEP ), University of East Anglia [Norwich] (UEA), Museo di Scienze, Trento, Museo di Scienze Trento, Department of Chemical Engineering [Loughborough], Loughborough University, Institut de Systématique, Evolution, Biodiversité (ISYEB ), Muséum national d'Histoire naturelle (MNHN)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Museum für Naturkunde [Berlin], Leibniz-Institut für Neue Materialien gGmbh (INM), Leibniz Association, Institut National de Recherche en Sciences Exactes et Naturelles (IRSEN ), Universität Trier, 30998360 - Burger, Marius, and 20274491 - Channing, Alan Eric
- Subjects
Male ,0301 basic medicine ,Amphibian ,0106 biological sciences ,media_common.quotation_subject ,Macroevolution ,Diversification (marketing strategy) ,Biology ,010603 evolutionary biology ,01 natural sciences ,03 medical and health sciences ,Phylogenetics ,biology.animal ,Genetics ,Animals ,Phylogeny ,Color evolution ,ComputingMilieux_MISCELLANEOUS ,Ecology, Evolution, Behavior and Systematics ,030304 developmental biology ,media_common ,Sex Characteristics ,0303 health sciences ,Dichromatism ,Pigmentation ,[SDV.BID.EVO]Life Sciences [q-bio]/Biodiversity/Populations and Evolution [q-bio.PE] ,Phylogenetic comparative methods ,Biological Evolution ,Sexual dimorphism ,Speciation ,030104 developmental biology ,Sexual selection ,Evolutionary biology ,Diversification ,Africa ,Afrobatrachia ,Trait ,Female ,Anura ,Regular Articles - Abstract
Theory predicts that sexually dimorphic traits under strong sexual selection, particularly those involved with intersexual signaling, can accelerate speciation and produce bursts of diversification. Sexual dichromatism (sexual dimorphism in color) is widely used as a proxy for sexual selection and is associated with rapid diversification in several animal groups, yet studies using phylogenetic comparative methods to explicitly test for an association between sexual dichromatism and diversification have produced conflicting results. Sexual dichromatism is rare in frogs, but it is both striking and prevalent in African reed frogs, a major component of the diverse frog radiation termed Afrobatrachia. In contrast to most other vertebrates, reed frogs display female-biased dichromatism in which females undergo color transformation, often resulting in more ornate coloration in females than in males. We produce a robust phylogeny of Afrobatrachia to investigate the evolutionary origins of sexual dichromatism in this radiation and examine whether the presence of dichromatism is associated with increased rates of net diversification. We find that sexual dichromatism evolved once within hyperoliids and was followed by numerous independent reversals to monochromatism. We detect significant diversification rate heterogeneity in Afrobatrachia and find that sexually dichromatic lineages have double the average net diversification rate of monochromatic lineages. By conducting trait simulations on our empirical phylogeny, we demonstrate that our inference of trait-dependent diversification is robust. Although sexual dichromatism in hyperoliid frogs is linked to their rapid diversification and supports macroevolutionary predictions of speciation by sexual selection, the function of dichromatism in reed frogs remains unclear. We propose that reed frogs are a compelling system for studying the roles of natural and sexual selection on the evolution of sexual dichromatism across micro- and macroevolutionary timescales.
- Published
- 2018
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