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Showing 1 to 20 of 31 for “"Cichlids"”.
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Genetic basis of adaptive radiation in East African cichlids
<p>East African cichlids are a paramount example of adaptive morphological radiation. The most dramatic difference among species occurs in oral jaw design and correlates with ecological niche partitioning. Convergent evolution of trophic forms between lakes suggests a common mechanism. What …
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Cichlids as a model for the evolution of visual sensitivity
<p>The cichlid fishes of East Africa are the most ecologically diverse radiation of recent vertebrates. These highly visual fish live in habitats ranging from turbid rivers to clear lakes. They have evolved to exploit an astounding array of foraging strategies. The combination of phenotypic …
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The Evolutionary biology and taxonomic review of Zambian riverine haplochromine cichlids
… among Zambian riverine haplochromine cichlids and at reviewing their taxonomic status. The riverine haplochromines used were from the Zambezi River and the Luapula-Congo River systems. The target taxa were from two major groups: the Serranochromine species and the Pseudocrenilabrus …
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Illuminating the Drivers of Genomic Diversification in Lamprologine Cichlids of the Lower Congo River
… adaptive evolution in rheophilic lamprologine cichlids endemic to the LCR, including <em>Lamprologus lethops</em>, the only blind cichlid fish are known to exist.</p> <p>I first focus on understanding the evolutionary relationships between four endemic lamprologine cichlid species distributed …
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The ecological, behavioral, and genetic factors influencing the diversification of Lake Malawi's rock -dwelling cichlids
<p>Rapid evolutionary radiations provide insight into the fundamental processes involved in species formation. Here I examine the diversification of one such group, the rock-dwelling cichlid fishes of Lake Malawi (mbuna), which have radiated from a single ancestor into more than 200 species over …
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Genetic variation in fast-evolving East African cichlid fishes: an evolutionary perspective
… via the genetic variation in East African cichlids. We generated a valuable cichlid genomic resource of five low-coverage Lake Malawi cichlid genomes, from which the general properties of the genome were characterized. Nucleotide diversity of Malawi cichlids was low at 0.26%, and a sample …
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Variation in neural crest development contributes to phenotypic diversification of East African cichlid fishes
… Despite low genetic divergence, East African cichlids harbour a spectacular intra- and interspecific morphological diversity. Akin to other vertebrates, a considerable proportion of hyper-diverse cichlid traits, such as craniofacial morphologies and pigmentation patterns, originates from a …
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Epigenetic variability and inheritance in East African cichlid fishes
… a high phenotype/genotype diversity ratio makes cichlids a promising system to investigate the role of genetics and, for the first time at a species level, epigenetics in the context of adaptation and convergent evolution. Yet, the molecular mechanisms and, in particular, any epigenetic aspects …
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Genetic structure and inversions in the Lake Malawi cichlid radiation
… a new variant callset of 2,198 Malawi cichlids from ~250 species and provide an overview of the genetic structure of the entire radiation. I then describe a new software that employs windowed principal component analysis to examine variation in genetic structure along chromosomes. This …
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Towards a Pangenome Perspective on the Lake Malawi Cichlid Radiation
… that there is little sequence divergence between cichlids at the level of single nucleotide polymorphisms (SNPs), with a 0.1 to 0.25% pairwise divergence quoted for Lake Malawi. However, most of these findings were based on aligning short reads to a single linear reference genome, which has the …
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The Effect of Gonadotropin Releasing Hormone on Opsin Gene Expression and Spectral Sensitivity in Zebra Cichlid Fish (Metriaclima zebra).
… The diversity in spectral sensitivity of cichlids has been partially attributed to differences in opsin gene expression, with each species preferentially expressing a subset of seven possible genes. Hormones such as gonadotropin releasing hormone (GnRH) can mediate changes in gene …
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Evolution and Development of Pigmentation Patterns in East African Cichlid fishes
… are an innovation unique to the haplochromine cichlids; yellow to red annular markings typically on male anal fins, made up of orange (xanthophores) and iridescent (iridophores) pigment cell types. The functional origin of egg-spots has been implicated in courting behaviour and sexual …
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Molecular Evolution of Visual System Genes in Fishes
… three fewer opsins than closely-related African cichlids, a difference partly due to duplication of a green-sensitive (RH2) opsin in African cichlids. In Chapter Four, this RH2 duplication event is studied in greater depth; variation in selective constraint is documented following gene …
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Male gamete morphology in relation to swimming velocity and fertilisation microenvironment
… topic of 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 …
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The generation and maintenance of diversity in a rapid adaptive radiation
… different aspects of the variation in the LM cichlids and the mechanisms generating and maintaining this level of diversity at multiple biological levels. Community-level diversity is investigated using null model analysis of species co-occurrence data. We detect signals of non-random …
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Sexual Selection and Mate Preference in Astatotilapia Burtoni
… the role of social behavior in African cichlids has been salient for their adaptive radiations in the East African Great Rift Lakes underlining the importance of social behavior for diverse evolutionary outcomes. While it has been widely reported that cichlids have complex social lives, …
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Offspring retrieval behaviors after brood loss in the convict cichlid
… young, including retrieval efforts. Convict cichlids (Amatitlania siquia) are an example of a monogamous biparental fish that show shared parental care of young. In the wild, these cichlids defend nests and search for missing young in response to complete or catastrophic brood loss. This …
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Relações filogenéticas do complexo de espécies "Cichlasoma" facetum com clados da tribo Heroini (Perciformes: Cichlidae)
… by KULLANDER (op. cit.) for the neotropical cichlids through nevralgic, miologic and osteologic studies.
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Transcriptional divergence during cichlid embryogenesis
… is generated during development. Moreover, cichlids are shown to have very low average nucleotide diversity within and between species. This low variation at the genomic level cannot fully explain the great diversity at the phenotypic level. Transcriptomes can thus serve as an intermediate …
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