Search for dissertations about: "divergence"

Showing result 1 - 5 of 288 swedish dissertations containing the word divergence.

  1. 1. Dating Divergence Times in Phylogenies

    University dissertation from Uppsala : Universitetsbiblioteket

    Author : Cajsa Lisa Anderson; Uppsala universitet.; [2007]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; systematic biology; divergence time; nonprametric rate smoothing; Bayesian; multidivtime; eudicots; Neoaves; monocots; dating; molecular clock; relaxed clock; age constraint; fossil; calibration; PATHd8; penalized likelihood; NATURAL SCIENCES Biology; NATURVETENSKAP Biologi;

    Abstract : This thesis concerns different aspects of dating divergence times in phylogenetic trees, using molecular data and multiple fossil age constraints.Datings of phylogenetically basal eudicots, monocots and modern birds (Neoaves) are presented. Large phylograms and multiple fossil constraints were used in all these studies. READ MORE

  2. 2. Postmating Sexual Selection and its Role in Population Divergence in Beetles

    University dissertation from Uppsala : Acta Universitatis Upsaliensis

    Author : Claudia Fricke; Uppsala universitet.; [2006]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Biology; Callosobruchus maculatus; postmating sexual selection; speciation; laboratory selection experiment; divergence; Biologi; NATURAL SCIENCES Biology; NATURVETENSKAP Biologi;

    Abstract : Speciation is the process describing the formation of new species and is at the heart of evolutionary biology. According to the biological species concept only reproductively isolated forms are regarded good species. This thesis aims at identifying evolutionary processes that cause population divergence and, ultimately, speciation. READ MORE

  3. 3. On Estimating Topology and Divergence Times in Phylogenetics

    University dissertation from Uppsala : Avdelningen för matematisk statistik

    Author : Bodil Svennblad; Uppsala universitet.; [2008]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Mathematical statistics; Phylogenetics; Divergence Time; Likelihood based methods; Non-informative prior; bootstrap support; Matematisk statistik;

    Abstract : This PhD thesis consists of an introduction and five papers, dealing with statistical methods in phylogenetics.A phylogenetic tree describes the evolutionary relationships among species assuming that they share a common ancestor and that evolution takes place in a tree like manner. READ MORE

  4. 4. The transience of American Swedish

    University dissertation from Lund University Press

    Author : Staffan Klintborg; Lunds universitet.; Lund University.; [1999]
    Keywords : HUMANIORA; HUMANITIES; transfer; pragmatic markers; nonce-borrowing; markedness; language loss; language death; language attrition; language alternation; divergence; convergence; continuum; contact linguistics; codeswitching; avoidance; American Swedish; automaticity; triggering; English language and literature; Engelska språk och litteratur ;

    Abstract : Popular Abstract in Swedish "Dom säjer de - do - dopey Swedes - but I tell you that - dom e inte så dopia" Avhandlingen beskriver språket som talas av den sista generationen svenska utvandrare till Nordamerika. Inflytandet från engelskan gör sig gällande på olika sätt, t.ex. READ MORE

  5. 5. On Speciation in Birds – Genomic Signatures across Space and Time

    University dissertation from Department of Biology, Lund University

    Author : Martin Stervander; Lunds universitet.; Lund University.; [2015]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; colonization; islands; isolation; introgressive hybridization; sympatry; natural selection; bill morphology; coalescence-based analyses; DNA sequencing; birds; divergence; Speciation;

    Abstract : Popular Abstract in Swedish Ända sedan Charles Darwin 1859 publicerade Om arternas uppkomst har just frågan om hur en art delas i två varit en central del av evolutionsbiologin. Darwin hade under resorna på HMS Beagle iakttagit hur bland annat härmtrastar och finkar på Galápagos varierade mellan öarna och drog slutsatsen att flera närbesläktade arter inom grupperna delade samma ursprung. READ MORE