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Full-Text Articles in Ecology and Evolutionary Biology

Using Conservation Genetics To Inform Reintroduction Of The Endangered Mottled Duskywing (Erynnis Martialis), Shayla Kroeze Apr 2022

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 …


From Individuals To Communities: The Effect Of Climate Change On Ectothermic Predators, Matthew Lawrence Meehan Apr 2022

From Individuals To Communities: The Effect Of Climate Change On Ectothermic Predators, Matthew Lawrence Meehan

Electronic Thesis and Dissertation Repository

The living components of ecological systems exist within a nested hierarchy, consisting of individuals, populations, and communities. Because of this nestedness, climate change can greatly impact ecological systems, as whole-organism metabolic and physiological demands change for ectotherms under warming, the effects of which may compound with every succeeding level. Therefore, a multi-level approach can better isolate how climate change will reshape ecological systems. In my doctoral research, I used feeding and mesocosm experiments to examine how climate change affects ectothermic predators at the individual-, population-, and community-level, using mesostigmatic mites (Arachnida: Parasitiformes) as my model predator. My research objectives were …


Diversity And Drivers Of Oribatid Mites (Acari: Oribatida) In Boreal Peatlands, Carlos Rafael De Araujo Barreto Nov 2021

Diversity And Drivers Of Oribatid Mites (Acari: Oribatida) In Boreal Peatlands, Carlos Rafael De Araujo Barreto

Electronic Thesis and Dissertation Repository

Boreal peatlands are important ecosystems for carbon cycling, storing 1/3 of the world’s terrestrial carbon in only ~3% of the globe, making them a key component of potential mitigation strategies in response to global climate warming. Experiments have shown that warming can affect plant and microbial communities in ways that potentially shift peatlands from carbon sinks to sources. Soil food webs, including the microarthropod community, are key in carbon cycling but are relatively understudied both in peatlands and under experimental warming. My research capitalized on a large-scale experimental field manipulation of warming in two contrasting peatland sites in Northern Ontario, …


Effects Of Dietary Thiaminase On Reproductive Traits In Three Populations Of Atlantic Salmon Targeted For Reintroduction Into Lake Ontario, Kimberly T. Mitchell Jan 2020

Effects Of Dietary Thiaminase On Reproductive Traits In Three Populations Of Atlantic Salmon Targeted For Reintroduction Into Lake Ontario, Kimberly T. Mitchell

Electronic Thesis and Dissertation Repository

The fitness of reintroduced salmonids in Lake Ontario can be reduced by high levels of thiaminase in exotic prey consumed at the adult stage. If sensitivity to dietary thiaminase differs among the three Atlantic salmon populations targeted for reintroduction into Lake Ontario, this could significantly influence their performance. I quantified the effects of experimental diets that contained high or low (control) levels of thiaminase on thiamine concentrations, survival, growth rate, and reproductive traits (sperm and egg quality) in Atlantic salmon from the three candidate source populations. Fish that consumed the high-thiaminase diet had comparable growth rates, but lower survival and …


Soil Homogenization: Plant Species Diversity, Ecosystem Properties And Soil Freezing Effects During Tallgrass Prairie Restoration, Holly J. Stover Jul 2018

Soil Homogenization: Plant Species Diversity, Ecosystem Properties And Soil Freezing Effects During Tallgrass Prairie Restoration, Holly J. Stover

Electronic Thesis and Dissertation Repository

Tillage can increase soil uniformity in former agricultural sites. Within plant communities, niche-based species sorting may occur among distinct soil patches (microsites), increasing diversity, and the interfaces between microsites (microedges) also may provide unique microsites. However, the influence of soil homogenization and microedges on ecosystem processes and plant responses to stress have not been examined. My thesis assessed if adding microsites containing sand, woodchips, pits or mounds increased plant species diversity, productivity, decomposition and nitrogen retention (15N tracer) and buffered plant responses to soil freezing in a tallgrass prairie restoration on former cropland. Homogenization decreased diversity in flat …


Wildlife In A Premier African Protected Area Do Not Perceive Ecotourists As Predators, Badru Mugerwa Apr 2018

Wildlife In A Premier African Protected Area Do Not Perceive Ecotourists As Predators, Badru Mugerwa

Electronic Thesis and Dissertation Repository

Researchers have reported that the presence of ecotourists may displace or disturb wildlife with potentially adverse effects, and may be a more serious problem if wildlife perceive ecotourists as predators. I used a playback experiment to test if wildlife at Bwindi Impenetrable National Park, Uganda, perceive ecotourists as predators. I contrasted wildlife behavioural responses to vocalizations that simulate those of ecotourists to those of local predators (positive controls; dogs and the extirpated native apex predator, leopard) and a non-predator (negative control; insects). Using responses from 14 mammal species, I show that wildlife do not perceive ecotourists as predators, responding no …


Cellular/Molecular Analysis Of Interspecies Sterile Male Hybrids In Drosophila, Rachelle L. Kanippayoor Jun 2017

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 …


Evolutionary Genetic Aspects Of Host Association In Generalist Ectoparasites, Benoit Talbot May 2017

Evolutionary Genetic Aspects Of Host Association In Generalist Ectoparasites, Benoit Talbot

Electronic Thesis and Dissertation Repository

Despite the use of the host for dispersal by most parasite species, the extremely loose relationship typical between highly mobile hosts and generalist ectoparasites may lead to very different gene flow patterns between the two, leading in turn to different spatial genetic structure, and potentially different demographic history. I examined how similar gene flow patterns are between Cimex adjunctus, a generalist ectoparasite of bats present throughout North America, and two of its key bat hosts. I first analyzed the continent-scale genetic structure and demographic history of C. adjunctus and compared it to that of two of its hosts, the …


Exploration Of Spatial And Temporal Changes In Trophic Status Of Lakes In The Northern Temporal Forest Biome Using Remote Sensing, Aleksey Paltsev Apr 2015

Exploration Of Spatial And Temporal Changes In Trophic Status Of Lakes In The Northern Temporal Forest Biome Using Remote Sensing, Aleksey Paltsev

Electronic Thesis and Dissertation Repository

There is a critical need for detailed surveys of lakes covering large spatial (>100 km2) and temporal scales (decades) to determine if there is an increase in the magnitude and frequency of phytoplankton blooms. Remote sensing was used to: (1) develop a regression model that relates chlorophyll a (chl-a) as a proxy of lake phytoplankton biomass to Landsat TM and ETM+ optical reflectance (r2=0.85, p


Testing For Positive Edge Responses In A Fragmented Landscape In The Eastern Tiger (Papilio Glaucus) And The Spicebush (P. Troilus) Swallowtail Butterflies, Jenna C. Siu Apr 2014

Testing For Positive Edge Responses In A Fragmented Landscape In The Eastern Tiger (Papilio Glaucus) And The Spicebush (P. Troilus) Swallowtail Butterflies, Jenna C. Siu

Electronic Thesis and Dissertation Repository

Landscape changes such as habitat fragmentation and habitat loss are contributing to a global decline in biodiversity. While habitat fragmentation research has mainly focused on species that avoid edges, or the boundaries between different landcover types (negative edge response), a hypothesized resource distribution model predicts that species that require complementary resources in different landcovers will be most abundant at edges (positive edge response). Adults of Eastern Tiger (Papilio glaucus) and Spicebush (P. troilus) swallowtail butterflies require forests for oviposition sites and meadows for nectar resources. I examined the relative abundance and flight orientation of both species …


Structure Of An Ensemble Of Insectivorous Bats, Matthew A. Emrich Jul 2013

Structure Of An Ensemble Of Insectivorous Bats, Matthew A. Emrich

Electronic Thesis and Dissertation Repository

Ensembles of species show distinct characteristics that may permit resource partitioning but few studies focus on more than one or two traits. Using seven sympatric Jamaican bats, I examined features which could allow for spatial, temporal, behavioural and dietary partitioning including wing morphology, echolocation characteristics, flight behaviour, habitat use, and diet. Using acoustic arrays I compared activity patterns at different sites to determine temporal and spatial partitioning and generated flight paths to determine flight speeds. From captured bats I measured wing morphology to examine morphological differences and did genetic analysis of guano to determine dietary partitioning. Morphology, call structure and …