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Showing 1 to 20 of 23 for “"Lake Malawi"”.
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EVOLUTION OF FRESHWATER CRABS IN LAKE MALAWI AND THE LAKE MALAWI BASIN IN THE EAST AFRICAN RIFT VALLEY
<p>Lake Malawi is the southernmost lake in the East African Rift Valley and is home to a single species of freshwater crab, the Malawi Blue Crab. Little is known about species diversity and the phylogenetic relationships of the freshwater crabs of Lake Malawi, in contrast to the lake’s …
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Genetic structure and inversions in the Lake Malawi cichlid radiation
… on the adaptive radiation of cichlid fishes in Lake Malawi, one of the most dramatic speciation events known in vertebrates. Following a general introduction, I first characterize a new variant callset of 2,198 Malawi cichlids from ~250 species and provide an overview of the genetic structure of …
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Towards a Pangenome Perspective on the Lake Malawi Cichlid Radiation
The cichlid fishes in the East African Rift lakes are one of nature’s most spectacular vertebrate radiations and form an excellent system to study the evolutionary process of speciation. Lake Victoria, Malawi and Tanganyika are each home to hundreds of species with a wide spectrum of sizes, …
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Patterns and process during the diversification of the cichlid fishes in Lake Malawi, Africa
<p>The 500-1000 cichlid species endemic to Lake Malawi constitute one of the most rapid and extensive radiations of vertebrates ever discovered. The objective of this dissertation was to test the assumptions and predictions of several recently published models of cichlid speciation. First, a novel …
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Inheritance of Dorsal Fin Coloration in the Metriaclima Species Complex (Teleostei: Cichlidae) of Lake Malawi
The rock-dwelling cichlids (mbuna) of Lake Malawi have undergone an explosive evolution, giving rise to an assemblage of 300-500 species within the last one million years. Most widespread mbuna 'species' are characterized by the presence of local endemic populations, differing primarily in …
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Population genetics of the cichlid, Cynotilapia afra (Günther 1894), in its native and introduced ranges in Lake Malawi
… the natural world. The cichlid species flock of Lake Malawi consists of an estimated 451-800 species and is a textbook example of explosive speciation that has been studied as a model system of evolution in the past three decades. In addition, fish are of major socio-economic importance to …
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An evaluation of lake and river levels as indicators of climate variability in tropical Southern Africa
Southern Africa has only a few.large lakes, one of which is Lake Malawi. It forms part of the lower Zambezi River catchment and is part of the Great Rift Valley. Lake Malawi plays a significant role in socio- economic development particularly in food production, health, energy, transport, …
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Genetic variation in fast-evolving East African cichlid fishes: an evolutionary perspective
Cichlid fishes from the East African Rift lakes Victoria, Tanganyika and Malawi represent a preeminent example of replicated and rapid evolutionary radiation. In this single natural system, numerous morphological (eg. jaw and tooth shape, color patterns, visual sensitivity), behavioral (eg. …
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The generation and maintenance of diversity in a rapid adaptive radiation
The Lake Malawi cichlid fishes are a pre-eminent example of adaptive evolutionary radiation. The diversity of species (nearly 1000 extant) is mirrored by an array of variation in dozens of phenotypes (e.g. trophic morphology, tooth shape, color patterns, behavior, development). The unique …
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Male gamete morphology in relation to swimming velocity and fertilisation microenvironment
… research focuses on cichlid fish. Cichlids from Lake Malawi have been underrepresented in the published literature in sperm biology despite being extensively studied in relation to other aspects of their biology. A phylogenetically controlled study into links between sperm morphology and velocity …
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Genetic basis of adaptive radiation in East African cichlids
… Convergent evolution of trophic forms between lakes suggests a common mechanism. What combination of intrinsic and extrinsic factors constitute this mechanism still remains to be seen. The goal of this dissertation was to examine the genetic basis of shape differences between two closely …
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Pre-rift evolution of Malawian high-grade basement rocks
… controversy in terms of the basement geology of Malawi which ultimately stems from the overall lack of metamorphic studies conducted in the area. The geological complexity of Malawi comes from that fact that it sits at the intersection of three major orogenic belts: The Palaeoproterozoic Ubendian …
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The Effect of Gonadotropin Releasing Hormone on Opsin Gene Expression and Spectral Sensitivity in Zebra Cichlid Fish (Metriaclima zebra).
… and the maintenance of species diversity in Lake Malawi cichlid fishes are greatly dependent on optical communication, which is influenced by environmental, physiological and endocrinological factors. The diversity in spectral sensitivity of cichlids has been partially attributed to …
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The ecological, behavioral, and genetic factors influencing the diversification of Lake Malawi's rock -dwelling cichlids
… such group, the rock-dwelling cichlid fishes of Lake Malawi (mbuna), which have radiated from a single ancestor into more than 200 species over the past 700,000 years. Through the examination of several molecular phylogenies, a phylogenetic history of the mbuna is proposed. The diversification of …
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Epigenetic variability and inheritance in East African cichlid fishes
… forming part of the radiation of East African Lakes show a remarkable diversity of phenotypic and ecological adaptation. Despite this, recent studies highlighted that genetic diversity within the radiation is among the lowest ever observed in vertebrates. Such a high phenotype/genotype …
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New insights into Transposable Elements from high quality genome sequences across diverse animals
… in the haplochromine cichlid fish radiation of Lake Malawi, uncovering the large diversity of transposable elements present in these cichlids and how they manifest different patterns of activity in different populations and species. To conclude this chapter I discuss different theories about the …
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Variation in neural crest development contributes to phenotypic diversification of East African cichlid fishes
… basis of NC-derived phenotypic diversity in Lake Malawi cichlids, focusing on the variation in development of the embryo, NC, and its derivatives. First, I demonstrate fundamental differences in multiple aspects of cichlid embryogenesis, including variation in morphology and timing, duration, …
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Heterogeneous Strain Distribution & the Effects of High Frequency Climate Change on the Evolution of Early-Stage Rift Systems: Case Studies from Lakes Tanganyika and Malawi (Nyasa), East Africa
… series of 12 regional cross sections across the Lake Tanganyika Rift, using the structural restoration tool Lithotect, constructed from newly reprocessed seismic reflection data in the depth domain. This rift transects a series of different terrains containing both pre-existing structures and …
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A role for environmental epigenetics in the rapid diversification of East African cichlid fishes
… establishing natural epigenetic variability in a lake environment. On the basis of ecomorphological diversity and genetic similarity, four species were selected from Lake Malawi, an ecosystem containing the most extensive cichlid adaptive radiation, which houses more fish species than any other …
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Transcriptional divergence during cichlid embryogenesis
… transcriptomics. The study focuses on two Lake Malawi cichlid species representing distinct eco- morphological groups: the ancestral-like generalist Astatotilapia calliptera and the specialized mbuna (rock-dwelling) algae-scraper Tropheops sp. ‘mauve’. Transcriptomic data are generated and …
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