Electronic Thesis or Dissertation

Acoustic communication is vital for mediating interactions between individuals and their environment. From echolocating bats to isolated rodent pups, ultrasonic vocalizations are a useful mechanism for producing localized and cryptic acoustic signals. Flying squirrels have been demonstrated to produce almost exclusively ultrasonic calls which is rare in both squirrels and mammals, though the significance of this acoustic range is unknown. To investigate the context of ultrasonic calls in these gliding mammals, I created phylogenetic comparative analyses to compare ecological and morphological traits against call frequencies. I found that nocturnality, a trait entangled with gliding in squirrels, was related to higher-frequency calls. Furthermore, by comparing all gliding mammals and their non-gliding counterparts, I found that gliding mammals produce significantly higher frequencies than these relatives. This form of cryptic communication is likely used to avoid predation, which was further supported by behavioural experiments wherein flying squirrels used significantly higher frequencies when predation risk increased. While high frequency communication was used by most gliders, I found that ultraviolet-induced photoluminescence, another potential form of crypsis, was strongly associated with nocturnality, with half of the tested gliding mammals showing evidence of this unique colouration. While ultrasonic vocalizations are widespread in echolocating bats and echonavigating mammals, I did not find evidence to support echonavigation in flying squirrels. Instead, I found that ultrasonic vocalizations are used in a variety of social contexts and during solitary foraging and exploration. These combined results demonstrate the unique ecological and evolutionary pressures acting on small-bodied, nocturnal gliding taxa and the resulting cryptic behaviours and communication.

Author Keywords: communication, flying squirrels, gliding mammals, Sciuridae, ultrasound, ultraviolet-induced photoluminescence

This thesis examines Beyoncé's art within the context of Black feminist thought, specifically focusing on how her work reflects and contributes to the themes of sisterhood, female empowerment, and intersectionality. A comprehensive analysis of her songs and performances will demonstrate how Beyoncé's art advocates for unity, female empowerment, particularly for Black women, and encourages sisterhood and support. The results reveal that Beyoncé's art serves as a powerful tool to challenge societal norms, address racial and gender inequalities, and advocate for justice, especially in the lives of Black women. Through her music and performances, Beyoncé has become a powerful example of using popular music as a medium for social change and cultural empowerment. This research highlights the significance of her contributions to the ongoing conversations surrounding race, gender, and socioeconomic factors, underlining the powerful influence of her art in encouraging a more inclusive society.

Author Keywords: Beyoncé, Black Feminist Thought, Female Empowerment, Gender inequalities, Intersectionality, Sisterhood

My research into Et'sehch'i, the Traditional Dene Burial Practices, is a comprehensive study into how smaller groups, clans, of our northern Dene understood and handled matters of funerals. The research focuses on the Dene community of Radelie Koe, Fort Good Hope in the Northwest Territories of Canada, my home community. In these Pre-Contact times, there weren't any of the modern tools we are now familiar with. The dead were interred on outdoor stages, raised platforms.

The most important part of Et'sehch'i involved the matriarch or another Elder of the clan hand-picking individual youths to help keep the Community together. They kept together as a group, going around together, cutting wood for people, hauling water or ice and generally reinstalling joy into the People's lives. Another form of these coming-of-age ceremonials involved young girls becoming women. The research involves the ways in which the Dene handled anything to do with major changes throughout our history. It was mandated by the Elders Council and Band Council of Fort Good Hope and followed a community protocol of respect for culturally sensitive material. These traditions, following ethical standards, account in good part for our survival from a time we call "When the World was New", from dinosaurs to today's computers.

Keywords: Dene Community, Burial Practice, Et'sehch'i, Ceremony, Funeral, Youth, Painting, Ceremonial Practice, Ways of Being

Author Keywords: Burial Practice, Ceremony, Dene Community, Et'sehch'i, Funeral, Painting

This dissertation focuses on the intersectionality between images posted on social media and social rules in the lives of young people. The findings are based on thirty-four qualitative interviews with young social media users where photo-based methodologies were employed. From these interviews, three key themes emerged: 1) Posting and sharing images are connected to identity exploration and formation, 2) Social rules around embodied emotions affect how youth present their emotions in online photographic material, and 3) The conflation of private and public spaces in the digital sphere complicates how social media users interact with images. While the findings presented are clear, this dissertation aims to take a holistic approach to understanding youth digital culture and avoids coming to conclusions that view social media as "good" or "bad" for youth. This tactic allows the findings to acknowledge the complexities of communicative digital spaces and understand the intricacies of social media in the daily lives of young people (boyd, 2014; Tilleczek & Campbell, 2019). This dissertation discusses both challenges youth face on social media when posting and viewing images, as well as how images can be used to defy social norms.

Author Keywords: Affect, Culture, Image, Social Media, Youth

Fungi are a diverse group of organisms that play crucial roles in various ecological processes and have immense economic importance. Understanding the intricate mechanisms underlying fungal growth and development is fundamental to harnessing their potential and exploring their applications in different fields. Signalling molecules, such as hormones, have been identified as key regulators in fungal physiology, orchestrating intricate processes and modulating biological responses to the environment. Phytohormones, commonly associated with plants, have been proposed as potential myco-hormones due to their production in a wide variety of fungi. Metabolomic analyses were performed via LC-MS/MS to investigate the role of phytohormones, specifically cytokinins (CKs) and indole-3-acetic acid (IAA), along with lipids and energetic metabolites such as organic acids during the growth and development of the model fungus Sordaria macrospora. The results revealed a clear switch between CK ribosides and CK free bases during the ascosporegenesis stage, with increased levels of cZ and iP and decreased levels of iPR and cZR. A similar pattern was observed in the mutant strain smgpi1 but demonstrating higher levels of CK free bases and increased fruiting body formation compared to the wild type. These findings provide insights into the regulation of phytohormones especially during fungal fruiting body development. In terms of IAA, the levels increased during the transition to sexual development in all strains, with the per5 mutant, unable to produce lipids via the cytosol, demonstrating a higher concentration than the wild type. The interplay between energetic metabolites and IAA suggests a potential role in the transition to sexual development. Additionally, the dose-dependent effects of exogenous CK application were investigated, showing the potential of low concentrations, from 1 to 10 μM, of CKs in promoting biomass accumulation or sexual development. Furthermore, gene editing in S. macrospora was proposed as a future direction to explore the functions of CKs and other metabolites during fungal development. Overall, this research contributes to our understanding of phytohormone-mediated processes in fungi and opens avenues for future investigations in fungal biology.

Author Keywords: fungi, LC-MS, metabolomics, myco-hormone, phytohormone, sexual development

Mortuary archaeology presents a unique opportunity to compare cultural and biological factors within burial assemblages. This study expands upon the previous bioarchaeological research in the eastern portion of the Southern Maya Lowlands through a comparative mortuary analysis that highlights burial trends between the site of Ka'kabish, Belize, and surrounding settlements. Ka'kabish spans from the Middle Formative through to the Postclassic periods (ca. 800 BC to AD 1500) and signifies a diverse social-strata with burials ranging from a variety of ritual and domestic complexes. Ka'kabish displays a preference for primary interments of non-extended positioning, greater chultun (subterranean chambers) use than displayed regionally, potential ancestor veneration, and demonstrates a transition from public, monumental burials, to private, domestic burials, from the Middle/Late Formative to the Postclassic periods. Inter-site comparisons demonstrate that Ka'kabish's mortuary patterns do not directly fit within a specific regional trend; rather, Ka'kabish displays a wide range of influences from many sites in the surrounding lowlands.

Author Keywords: Belize, Ka'kabish, Lowlands, Maya, Mortuary, Southern

I tracked summer movements and activity of snowshoe hares (Lepus americanus) in southwestern Yukon, Canada, during their population cycle (2015–2022) to assess the primary drivers of movement. Hares exhibited variable movement and activity during the cycle, exhibiting increased home range size and higher daily displacement during low population densities. Males exhibited more dramatic increases in their home ranges (>3-fold), and had greater and more variable movement rates and time spent travelling than females. The ratio of predators to hares was highest at low hare densities when hares were moving most, and seasonal activity of hares seemed unrelated to that of predators. Differences between sexes imply that reproductive activities likely were the main driver of hare movement variation rather than food availability. These findings reinforce that, even in highly variable environments, potential rewards associated with successful mate search and reproduction may outweigh the risks associated with reproductive behaviour.

Author Keywords: behaviour, boreal forest, GPS telemetry, home range, movement ecology, predation risk

Hybridization contributes to the genetic diversity and can impact speciation. This study investigates the genetic evidence of recent hybridization under climate change in sympatric populations of northern and southern flying squirrels in Ontario. Using low-coverage whole-genome sequences, my research examines the existing population structure and measures the genomic variation of the Glaucomys species. The global estimates of FST (0.308) and DXY (0.141) are indicative of substantial differentiation between the species. Measures of genetic diversity (π), differentiation (FST), and divergence (DXY) across the genome reveal insights into the divergent selection driving speciation. Results indicate an absence of contemporary hybridization or introgression at a site with longstanding sympatry. Across both species' genomes, signatures of selection align with four different scenarios for the formation of genomic landscapes of differentiation, shedding light on the complex speciation history of these flying squirrels. These findings enhance understanding of evolutionary dynamics, adaptation, speciation, and genetic differentiation.

Author Keywords: Genomic differentiation, Glaucomys, northern flying squirrel, southern flying squirrel, speciation

Muskrat populations are declining across North America. In recent decades, hybrid cattail Typha x glauca has been invading wetlands in North America. This invasion is degrading wetland habitat, leading to reduced interspersion of water and vegetation. Muskrats are wetland-obligates and their populations are positively linked to marsh interspersion. Therefore, muskrat populations may be declining due to the invasion of T. x glauca and subsequent reduction in interspersion. To test this hypothesis, I first sampled marshes across south-central Ontario, comparing muskrat densities with the relative frequency of T. x glauca and the degree of interspersion. Second, I measured intensity of use by muskrats in a large wetland along a gradient of interspersion. My findings suggest that reduced interspersion may be contributing to muskrat population declines, but it is unclear to what degree T. x glauca is responsible. Further research is needed to understand the effects of wetland invasions on muskrat populations.

Author Keywords: invasive species, Ondatra zibethicus, Southern Ontario, Typha x glauca, wetlands, wildlife conservation

Eutrophication is an ongoing global problem and agriculture is an important non-point source of nutrient loading. Specifically, nitrogen (N) and phosphorus (P) losses from agricultural landscapes continue to drive water quality issues. In southern Ontario, agriculture has intensified in recent decades, with major expansions of cash crop production and extensive tile drainage (TD). Through intensive monitoring of 12 tile outlets draining operational fields under the conventional corn-soybean-wheat rotation, this study examined differences in measured and volume-weighted total P, total N, and nitrate-N concentrations and loads over 28 months (October 2020- April 2023) amongst crop covers and between growing (GS; May – September) and non-growing seasons (NGS; October – April). Nitrogen concentrations (i.e., TN and NO3-N) in TD eluent were consistently high both between seasons and were found to be significantly highest from winter wheat (WW) fields in the NGS, and corn fields in the GS. Volume-weighted TP concentrations were not significantly different either amongst crop covers or between seasons, although TP losses tended to be highest from the cover crop (CC) fields in the NGS. Differences in N and P losses between years and amongst crop covers were attributed to differences in legacy soil nutrients, the establishment and decomposition of over-winter cover crops, and physical soil properties. The results of this study can inform agricultural management by addressing the urgent need for improved information around the relationship between agricultural practices and nutrient losses, especially in the NGS.

Author Keywords: Best management practices, Crop rotation, Over-winter cover crops, Seasonality, Tile drainage, Water quality