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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
331

Testing hypotheses in molecular ecology: genetic exchange and hybrid performance

Holleley, Clare Ellen, Biological, Earth & Environmental Sciences, Faculty of Science, UNSW January 2009 (has links)
Population structure, gene flow and dispersal are some of the most commonly estimated population parameters in population genetics, evolutionary biology and conservation genetics. The primary aim of thesis is to test the precision and accuracy of genetic estimates of population structure, gene flow and dispersal. The controlled replicated Drosophila melanogaster experiments of known effective population size (Ne = 14.3) and dispersal rate (m = 0.0025 - 0.04) all adhered to Wright??s demographic island model. Three statistical approaches were empirically tested: 1) the conversion of population structure to gene flow using FST, RST, SHUA and PhiST ; 2) the private alleles method to estimate gene flow; 3) a Bayesian assignment method to estimate dispersal (BAYESASS 1.2). Even in the best-case scenario, almost all current methods except SHUA significantly underestimate population structure, and consequently overestimate gene flow and dispersal when applied to real populations. It was crucial to ensure that the manipulated rate of gene flow was correctly defined. This led to three supporting investigations of hybrid performance, inversion polymorphisms and effective population size. The hybrid performance investigation demonstrated that the manipulated rate of gene flow had not been unexpectedly inflated by hybrid vigour or reduced by breakdown. These experiments also demonstrated that close inbreeding is not a necessary precondition for hybrid vigour or breakdown, which is important for conservation strategies involving induced dispersal. The investigation of inversion polymorphisms ensured that the manipulated rate of gene flow was not affected by selection on inverted regions. The effective population size investigation used a temporal estimation method to confirm that the Ne was accurately predicted by an N:Ne ratio of 0.286. Additionally this experiment showed that the single-sample estimation methods implemented by ONeSAMP or LDNE resulted in downwardly biased estimates of Ne in structured populations. In conclusion these results call into question the confidence that biologists may have in some of the most widely used molecular tools in conservation biology.
332

Population fluctuations in mountain hares : a role for parasites? /

Newey, Scott-John, January 2005 (has links) (PDF)
Diss. (sammanfattning) Umeå : Sveriges lantbruksuniversitet, 2005. / Härtill 6 uppsatser.
333

Temporal and spatial dynamics of willow grouse Lagopus lagopus /

Hörnell-Willebrand, Maria, January 2005 (has links) (PDF)
Diss. (sammanfattning) Umeå : Sveriges lantbruksuniversitet, 2005. / Härtill 5 uppsatser.
334

Mortality in rural Vietnam : validity of routine reporting and experiences from a surveillance system /

Huy, Tran Quang, January 2007 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 4 uppsatser.
335

The ecology and population biology of two litter decomposing basidiomycetes /

Murphy, John F., January 1992 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaves 117-125). Also available via the Internet.
336

Mesure et analyse de l'effet fondateur dans les populations de Charlevoix et du Bas-Saint-Laurent /

Gagnon, Nicolas, January 1998 (has links)
Mémoire de maîtrise (M.Med.Exp.)--Université du Québec à Chicoutimi, 1998. / Document électronique également accessible en format PDF. CaQCU
337

Residential density and building planning /

Tong, Tung. January 1994 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1994. / Includes bibliographical references (leaves 76-77).
338

Population studies on the Gm and Inv antigens in Asia and Oceania

Schanfield, Melvin Samuel, January 1971 (has links)
Thesis (Ph. D.)--University of Michigan, 1971. / Includes bibliographical references (leaves 106-110).
339

Genetic variation and local adaptation in peripheral populations of toads

Rogell, Björn, January 2009 (has links)
Diss. (sammanfattning) Uppsala : Uppsala universitet, 2009. / Härtill 5 uppsatser.
340

Land use and population regulation vole dynamics in a grazing experiment /

Fernandez de la Pradilla Villar, Jose Ignacio. January 2009 (has links)
Thesis (Ph.D.)--Aberdeen University, 2009. / Title from web page (viewed on Mar. 30, 2010). Includes bibliographical references.

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