Sökning: "genetic purging"

Visar resultat 1 - 5 av 9 avhandlingar innehållade orden genetic purging.

1. 1. Genomics of population decline

   Författare :Tom van der Valk; Katerina Guschanski; Aylwyn Scally; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; genetic diversity; minimal-invasive samples; population decline; inbreeding; genetic purging; eastern gorillas; Dryas monkey; Biologi med inriktning mot zooekologi; Biology with specialization in Animal Ecology;

   Sammanfattning : With human populations forecasted to grow in the next decades, many mammals face increasing anthropogenic threats. The consequential population declines are a precursor to extinctions, as small populations are not only more sensitive to stochastic events, but reduction in population size is generally also followed by a decrease in genetic diversity, which in turn reduces adaptive potential and fitness of the population. LÄS MER

3. 2. Gene transfer by interspecific hybridization in bryophytes

   Författare :Weerachon Sawangproh; Biodiversitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; homozygote; heterozygote; admixture; single nucleotide polymorphism; STRUCTURE; PCoA; hybrid index; inbreeding; outbreeding; hybrid depression; heterosis; phylogeny; purging selection; genetic purging; genotype; phenotype; sympatry; allopatry;

   Sammanfattning : The role of hybridization in evolution has been debated for more than a century regarding bryophytes (mosses, liverworts, and hornworts) as well as most other organisms. Bryophytes have haplodiplontic life cycles with a dominant haploid generation. LÄS MER

4. 3. The use of museum specimens in conservation genomics

   Författare :Johanna von Seth; Love Dalén; Karin Norén; Gernot Segelbacher; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; conservation genomics; museum specimens; genomic erosion; diversity; inbreeding; mutational load; genetic drift; purging; population divergence; local extinction; population decline; Sumatran rhinoceros; kakapo; arctic fox; Chatham Island black robin; Systematic Zoology; zoologisk systematik och evolutionsforskning;

   Sammanfattning : In the face of an increasing number of species being threatened by extinction, museum collections can constitute a powerful resource for acquiring genomic data of endangered taxa. By utilising datasets that combine genomes from present-day populations with those from historical timepoints, several questions relevant for conservation can be investigated. LÄS MER

5. 4. Genetic variation and population differentiation in the forest herb Lathyrus vernus (Fabaceae)

   Författare :Katarina Schiemann; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; chemotaxonomy. Physiology of nonvascular plants; Systematisk botanik; taxonomi; morfologi; kemotaxonomi. Växters fysiologi inte kärlväxter .; taxonomy; morphology; phytogeography; inbreeding depression; Systematic botany; small population size; marginality; reproductive characters; leaflet shape; allozymes; Lathyrus vernus; genetic variation;

   Sammanfattning : In the present thesis, I investigated patterns of genetic variation in the forest herb Lathyrus vernus (Fabaceae), using plant material from different-sized populations representing three geographically separated regions: central Europe, southern and central Sweden. My studies included presumably neutral or weakly selected characters (allozymes and leaflet shape) as well as characters that should be under strong directional selection (e. LÄS MER

7. 5. Island biogeography and population divergence in the Skyros wall lizard

   Författare :Anna Runemark; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Podarcis gaigeae; inbreeding; predation release; polymorphism; island gigantism; the island rule; genetic drift; sexual selection; natural selection; island biology; Evolution;

   Sammanfattning : Islands are cradles for new biodiversity and provide natural laboratories for the study of population divergence. In my thesis, I investigated the role of different evolutionary processes in the population divergence in the Skyros wall lizard (Podarcis gaigeae), a species where islet populations have strongly diverged morphologies. LÄS MER