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Genetic Analysis Of Male-Specific Lethality Between Caenorhabditis Briggsae:: Caenorhabditis Nigoni F1 Hybrids, Vaishnavi Ragavapuram
Genetic Analysis Of Male-Specific Lethality Between Caenorhabditis Briggsae:: Caenorhabditis Nigoni F1 Hybrids, Vaishnavi Ragavapuram
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Speciation occurs when there is a lack of reproduction due to genetic barriers. These genetic barriers to gene flow are referred as reproductive isolation mechanisms. Pre-zygotic and post-zygotic isolation are types of reproductive isolation mechanisms. In this project, post-zygotic isolation mechanisms were examined. Haldane's Rule states that in F1 hybrids, individuals of the heterogametic sex are less fit than those of the homogametic sex. Darwin's Corollary to Haldane's rule states that there is asymmetry in hybrid progeny between interspecific reciprocal crosses. Crosses done between Caenorhabditis briggsae males to Caenorhabditis nigoni females produce viable F1 hybrid females and males, yet the …
Genomic Signatures Of Population History In A Pair Of Recently Diverged Australian Teal Support Strong Selection On The Z Sex-Chromosome, Kevin Kyle Hawkins
Genomic Signatures Of Population History In A Pair Of Recently Diverged Australian Teal Support Strong Selection On The Z Sex-Chromosome, Kevin Kyle Hawkins
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Sex chromosomes are thought to be an important component of the genome associated with speciation and the buildup of reproductive isolation. Recent advances in sequencing technologies and improvements in population genetics and modeling techniques have made it possible to better assess genomic signatures of selection, genetic drift and gene flow in diverging lineages. Recent studies have shown elevated differentiation on the Z sex-chromosome between the Australian grey teal (Anas gracilis) and chestnut teal (Anas castanea). Here, we used next generation sequencing to scan ~3,400 autosomal loci and ~190 Z loci to examine genomic differentiation and signatures of selection and gene …
The Genomics Of Speciation Within The Globally Distributed Blue-Winged Ducks, Joel Thomas Nelson
The Genomics Of Speciation Within The Globally Distributed Blue-Winged Ducks, Joel Thomas Nelson
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The ability to disperse over long distances can result in a high propensity for colonizing new geographic regions and lead to lineage diversification via allopatric speciation. However, high vagility can also result in gene flow between otherwise allopatric populations, and in some cases, parapatric or divergence-with-gene-flow models of speciation might be more applicable to widely distributed lineages. Here, I used five nuclear introns and the mitochondrial control region to examine divergence, gene flow, and phylogenetic relationships within a cosmopolitan lineage comprising six species, the blue-winged ducks (genus Anas), which inhabit all continents except Antarctica. I found two primary sub-lineages, the …