Ecology and Evolutionary Biology Commons^™

Using Conservation Genetics To Inform Reintroduction Of The Endangered Mottled Duskywing (Erynnis Martialis), Shayla Kroeze

Electronic Thesis and Dissertation Repository

Habitat loss and climate change have caused declines in species diversity and abundance globally, including in butterflies which are important components of many ecosystems. Reintroductions are increasingly used to reverse diversity loss but are most effective when informed using genetics. I developed 24 microsatellites and characterized genetic structure and diversity of the endangered Mottled Duskywing (Erynnis martialis) in Ontario and neighbouring provinces and states. These were used to inform a planned reintroduction in Ontario. Populations had moderate levels of genetic diversity, however all but the largest populations may be subject to appreciable levels of genetic drift. Populations more …

Chemical Communication In Songbirds, Leanne A. Grieves

Electronic Thesis and Dissertation Repository

Avian chemical communication has been understudied due to the misconception that olfaction is unimportant or even lacking in birds. Early work focused on the olfactory foraging capabilities of seabirds because of their ecology (open ocean foraging) and large olfactory bulbs. In contrast, olfaction in passerine birds, comprising over half of all extant avian taxa, was long overlooked due to their relatively small olfactory bulbs. It is now well established that passerines can smell, and their olfactory acuity is comparable to that of macrosmatic mammals such as rats. Much of our theory on communication and mate choice has involved studying visual …

The Fruitless Gene Influences Female Mate Preference In Drosophila, Tabashir A. Chowdhury

Electronic Thesis and Dissertation Repository

Species can arise as a result of reproductive barriers that prevent gene flow between diverging populations that force them to remain isolated from one another. Behavioural isolation is one of the earliest acting reproductive barriers determined by the evolution of mating preferences that prevent inter-specific matings. Several traits have been identified that contribute to behavioural isolation, but the genetic basis of interspecific female preference is yet to be determined. I used genetic mapping techniques to identify and confirm that the fruitless gene is affecting species-specific female rejection of interspecies males, contributing to the behavioural isolation between Drosophila melanogaster and D. …

Spatial And Temporal Patterns Of Neutral And Adaptive Genetic Variation In The Alpine Butterfly, Parnassius Smintheus, Maryam Jangjoo

Electronic Thesis and Dissertation Repository

Understanding how much genetic diversity exists in populations, and the processes that maintain that diversity, has been a central focus of population genetics. The evolutionary processes that determine patterns of genetic diversity depend on underlying ecological processes such as dispersal and changes in population size. In this thesis, I examine the influence of dispersal and population dynamics on neutral and adaptive genetic variation in a naturally occurring network of populations of the alpine butterfly, Parnassius smintheus.

My first objective was to determine the combined consequences of demographic bottlenecks and dispersal on neutral genetic variation within and among populations. Using …

Cellular/Molecular Analysis Of Interspecies Sterile Male Hybrids In Drosophila, Rachelle L. Kanippayoor

Electronic Thesis and Dissertation Repository

Over time, genetic differences can accumulate between populations that are geographically separated. This genetic divergence can lead to the evolution of reproductive isolating mechanisms that reduce gene flow between the populations and, upon secondary contact, result in distinct species. The process of speciation is, thus, what accounts for the multitude of species that contribute to the rich biodiversity on Earth. Interspecies hybrid sterility is a postzygotic isolating mechanism that affects the development of hybrids, rendering them sterile. A notable trend, known as Haldane's Rule, describes that heterogametic individual (e.g. males in Drosophila) are more susceptible to sterility than homogametic …

Mhc Class Iiβ Diversity As A Correlate Of Neutral-Locus Similarity And Diversity, And A Predictor Of Overwinter Return, In Song Sparrows (Melospiza Melodia), Matthew J. Watson

Electronic Thesis and Dissertation Repository

Abstract

The major histocompatibility complex (MHC) is a family of genes involved with recognizing pathogens and mounting an immune response. Parasite-mediated selection often favours heterozygosity at MHC because MHC-diverse individuals recognize a wider range of pathogens. Because migratory birds encounter many pathogens, I hypothesized that MHC diversity predicts overwinter and juvenile survivorship in song sparrows (Melospiza melodia). I found no correlation between MHC diversity and neutral-locus (microsatellite) heterozygosity, suggesting that measures of neutral and adaptive genetic diversity provide complementary rather than redundant information. However, pairwise similarity at MHC predicted pairwise similarity at microsatellite loci. In contrast to my hypothesis, MHC …