Master of Arts, The Ohio State University, 1921, Graduate School

Committee: Not Provided (Other) Subjects:

MS, University of Cincinnati, 2024, Arts and Sciences: Biological Sciences

Movement is a fundamental process in the life of many organisms, and is necessary for individuals to acquire resources, avoid predation, find mates, and thermoregulate. Movement allows individuals to track suitable temperatures; movement, however, can be impacted by meteorological conditions. Due to climate change, global temperature is predicted to increase by 1.5 °C between 2030 and 2052, resulting in higher mean temperatures and more frequent extreme temperature events. Increasing temperatures may decrease the ability of organisms to move in response to these higher temperatures. Understanding how species will respond to climate change requires understanding how temperature and environmental conditions affect their movement. The first chapter of this work looks at the literature that examines the effect of temperature on the flight of butterflies at their northern- and southernmost ranges, given reported thermal flight limits of each species. Due to their limited life spans, sensitivity to environmental changes in their habitats, and relatively rapid responses to these changes, butterflies are often used as biodiversity indicators to gauge shifts in ecological processes, making them a popular group of ectotherms used to examine the effect of temperature on movement. Current (2010-2019) daily maximum temperatures during flight seasons were significantly greater than those reported in the 1950s at both northern and southern range limits. At the southernmost ranges, the current average number of days that maximum temperatures exceeded the upper thermal limits for butterfly flight were significantly greater than in the 1950s, while there was no statistically significant difference at the northernmost ranges. Increases in ambient temperatures can restrict an organism's ability to escape extreme local temperatures. While I found very few papers that state the effect of ambient temperature on flight, my analysis shows that incorporating the environmental temperat (open full item for complete abstract)

Committee: Stephen Matter Ph.D. (Committee Chair); Elizabeth Hobson Ph.D. (Committee Member); Patrick Guerra Ph.D. (Committee Member) Subjects: Biology

Master of Arts, Miami University, 2023, Geography

In the Midwestern USA (Southwest Ohio), landscape heterogeneity is changing drastically due to exurbanization. Recent studies suggest that an increase in landscape heterogeneity can have a positive effect on species diversity, abundance, and community composition, making this an exemplary location to research the effects of landscape modifications on species richness and composition. Lepidoptera (butterflies) in particular have been documented to be effective indicators of compositional and configurational landscape heterogeneity shifts which naturally make them a great model organism to study this novel system. Applying the concept of fragmentation per se, I found compositional heterogeneity to be a significant indicator of species richness and diversity. In contrast, configurational heterogeneity did not have an effect on lepidoptera. This suggests that fragmentation per se and increased compositional heterogeneity may have a positive effect on butterfly richness regardless of the configurational heterogeneity. Thus, conservation efforts should focus on diversification of the landscape cover types as well as supporting the conservation of small and large habitat patches.

Committee: Amelie Davis (Advisor); Mary Henry (Committee Member); Michelle Boone (Committee Member) Subjects: Biology; Conservation; Ecology; Environmental Science; Geography; Physical Geography; Remote Sensing

MS, University of Cincinnati, 2023, Arts and Sciences: Biological Sciences

Feeding adaptations occur in many organisms due to their diets and foraging strategies, impacting the morphological structure of their mouthparts and, ultimately, their survival. Lepidopterans have a mouthpart known as a proboscis and this long, thin, tube-like structure allows butterflies to access nectar from flowers. Previous studies have shown a positive correlation between the corolla length of certain flowers and the proboscis length of the insects that feed from those flowers, demonstrating the benefit of having a longer proboscis to access a wider variety of flowers. Within Lepidoptera, monarch butterflies (Danaus plexippus) are a unique study system because of their multi-generational migration. In the summer, a generation of non-migratory monarchs stays in the northern regions of Eastern North America. In the fall, their offspring migrate southwards to Mexico where they overwinter, and they then remigrate northwards during the following spring. Previous research has already determined morphological differences between migratory and non-migratory monarchs, but it is unknown whether the length of their proboscis is also affected by migratory status. Even though the proboscis is not directly linked to flight, it is still important to consider because it is how migratory monarchs access the nutrients along the way that are needed to sustain such a long flight during migration. Since the length of the proboscis plays such a vital role in lepidopteran feeding and survival, it is important to consider what factors might affect proboscis length. In this study, I measured the proboscises of monarchs and other non-migratory butterflies in Ohio to understand how proboscis length is affected by the following factors: 1) seasonality or migratory status, 2) sex, and 3) developmental conditions and anthropogenic influences. Other butterfly species were included in this study to determine whether any trends found in monarchs also extend to other butterflies, or if (open full item for complete abstract)

Committee: Patrick Guerra Ph.D. (Committee Chair); Stephen Matter Ph.D. (Committee Member); Theresa Culley Ph.D. (Committee Member) Subjects: Biology

Doctor of Philosophy, Case Western Reserve University, 2023, Biology

When multiple avenues to cope with novel environments are available, understanding the interaction of mechanisms and which traits are involved provides a more complete picture of organismal responses. In many instances, the mechanism, i.e., whether phenotypic changes are environmentally induced (phenotypic plasticity) or evolved, is often unknown but has important consequences for population persistence. I investigate interactions between mechanisms of phenotypic changes and how interactions between suites of related traits shape organismal responses to novel environmental temperatures by using the climatic warming caused by the urban heat island effect. Specifically, I examine evolution in thermal traits (thermal melanin and thermal tolerance limits), in the cabbage white butterfly (Pieris rapae L.), a common urban inhabitant. Further, I examine how evolution, or lack thereof, in these traits could be related to thermoregulatory behavior, as changes in behavior can mediate how organisms are exposed to selection. For thermal melanin, I found that wing melanin evolved to meet expectations based on thermal function, though responses were complicated by the multiple functions of melanin and the unique functions of melanin characters in each sex. For thermal tolerance, I found that there was no evidence of trait divergence between urban and rural populations, an outcome I expected based on the thermal flexibility, of P. rapae; however, I found that thermal limits were surprisingly not particularly plastic in response to temperature. Because of the complex responses found in thermal melanin and the surprising lack of thermal tolerance plasticity, I examined thermoregulatory behavior in urban and rural butterflies to see if behavioral differences could have influenced trait evolution. I found butterflies from both populations were able to maintain similar body temperatures through microhabitat selection. I also found that urban butterflies were more active in flight, p (open full item for complete abstract)

Committee: Sarah Diamond (Advisor); Patrick Lorch (Committee Member); Karen Abbott (Committee Member); Ryan Martin (Committee Member) Subjects: Biology; Ecology; Entomology; Evolution and Development; Organismal Biology; Physiology

Doctor of Philosophy, The Ohio State University, 2023, Food, Agricultural and Biological Engineering

Global population is projected to increase by 3.2 billion by 2050, thereby challenging agricultural systems to supply demands for food, feed and fiber needs of the growing population. Despite significant advancements in agriculture that allowed production systems to substantially increase productivity, farmers are still expected to produce more with less land, water, soil quality, and expanding pressures from insect pests, which remain a major limiting factor in agricultural production systems. Currently, one of the major limiting factors of agriculture is fall armyworm (Spodoptera frugiperda). This pest is highly notorious due to its polyphagous nature, that allows it to feed on over 350 different plant species, causing significantly reduced yields and large financial losses. Additionally, fall armyworm has high reproductive output, especially when food resources are abundant and weather conditions favorable. Fall armyworm also has the ability to migrate considerably long distances and has outstanding adaptive capabilities that have contributed to the development of resistance to many control tactics, including synthetic insecticides and Bt crops. Given the threat fall armyworm represents to production systems and food security, integrated pest management programs need to be optimized and implemented. In order to optimize integrated pest management programs, current strategies can be combined and/or improved and novel alternatives must be developed and implemented. Therefore, the goals of this dissertation are to evaluate current and novel alternative strategies to further improve fall armyworm pest management in corn and other relevant crops. Additionally, some of the alternatives described are pertinent for Bt resistance management for fall armyworm. In Chapter 2, the efficacy of different nanoparticles (i.e., Chitosan, Perfluorocarbon and Poly lactic-co-glycolic acid (PLGA) nanoparticles) and its potential to cause gene silencing (RNAi, RNA interference) in (open full item for complete abstract)

Committee: Andrew Michel (Advisor); Kelley Tilmon (Committee Member); Christopher Ranger (Committee Member); Peter Piermarini (Committee Member); Luis Cañas (Committee Member) Subjects: Entomology

Doctor of Philosophy, The Ohio State University, 1979, Graduate School

Committee: Not Provided (Other) Subjects: Biology

Doctor of Philosophy, The Ohio State University, 1976, Graduate School

Committee: Not Provided (Other) Subjects: Biology

BS, Kent State University, 2016, College of Arts and Sciences / Department of Biological Sciences

Butterflies and moths (Lepidoptera) represent the second most diverse taxa of animals with approximately 160, 000 named species. Lepidoptera feed on various liquids (e.g., nectar, sap, rotting fruit, blood) using specialized mouthparts (proboscis) that function as a conduit for transporting fluids from pools and wetted surfaces to the insects gut. Most previous reports assume (via gross morphology) that the proboscis functions as a drinking straw; fluid rise is coupled with sucking pump action and requires minor capillary influence. Recent research, however, has provided evidence that the proboscis incorporates capillarity and wettability dynamics for fluid rise. In addition, butterflies with partially split mouthparts were recently demonstrated to retain their feeding ability. The purpose of this project is to study fluid rise abilities in proboscises where the sucking pump has been disabled and to determine if butterflies can feed with completely split proboscises. Capillary action, wettability, and structural architecture play a more important role in fluid rise abilities in split proboscises (C-shaped conduit) than the sucking pump. Butterflies were also shown to retain their ability to feed with completely split proboscises, however, the sucking pump may be important for transporting fluids down the alimentary canal. The ability for fluids to travel against gravity in C-shaped conduits has application to the field of microfluidics for the production of microfluidic devices.

Committee: Matthew Lehnert (Advisor) Subjects: Entomology

BS, Kent State University, 2015, College of Arts and Sciences / Department of Biological Sciences

Transition areas between different habitat types or ecosystems can contain distinctive assemblages of communities. These areas, known as `ecotones', can provide useful data for biodiversity conservation because of their often-unique characteristics. However, the importance of ecotones varies with habitats and many biotic and abiotic characteristics. The responses of different organisms to ecotones are also diverse and need to be tested independently. In this study, bees, wasps, flies, and moths were collected in Fall 2013 and Fall 2015 to examine how their biodiversity differs by habitat type, at the ecotones, and across years. These surveys determined what species are found in which habitat types and if the composition of species differs at ecotones. The study area contained four main habitat types: upland forest, bottomland forest, the riparian/floodplain forest, and a stream. I hypothesized that the diversity of the flying insects listed above would differ by habitat with bottomland forest plots having the highest biodiversity due to habitat complexity. Second, I hypothesized that biodiversity will be greatest at the ecotones, and that there will be year-to-year differences. Analyses of variance found that bee and wasp diversity did not differ significantly by habitat type or across years, but moth and fly diversity did differ by habitat type. Ecotone analyses focused on ecotones between the three different forest types. Out of these three ecotone types, only one contained significant differences for bee and wasp species richness and abundance, as well as moth abundance. Qualitatively, there were more bee and wasp species sampled in 2015 than 2013, however, the results were not statistically tested. To better understand how their biodiversity is affected by ecotones, further research on the richness and abundance of these flying insect communities should investigate seasonal changes in how different landscape compositions affect how communities are a (open full item for complete abstract)

Committee: Mark Kershner (Advisor); Ferenc de Szalay (Committee Member); Dan Ross (Committee Member); Paul Sampson (Committee Member) Subjects: Biology; Ecology; Zoology

Doctor of Philosophy, The Ohio State University, 2005, Entomology

The phylogenetics, systematics, taxonomy, and biology of Gelechioidea (Insecta: Lepidoptera) are investigated. This superfamily is probably the second largest in all of Lepidoptera, and it remains one of the least well known. Taxonomy of Gelechioidea has been unstable historically. In Chapters Two and Three, I review the taxonomy of Gelechioidea and characters that have been important. Chapter Four provides the first phylogenetic analysis of Gelechioidea to include molecular data. I combine novel DNA sequence data from Cytochrome oxidase I and II with morphological matrices for exemplar species. The results challenge current concepts of Gelechioidea, suggesting that traditional morphological characters may not be homologous structures and are in need of further investigation. I conduct in Chapter Five an in-depth study of morphological evolution, host-plant selection, and geographical distribution of a medium-sized genus Depressaria Haworth (Depressariinae), larvae of which generally feed on plants in the families Asteraceae and Apiaceae. Host-plant use is commonly studied in this group because of physiological and behavioral responses exhibited by Depressaria pastinacella to furanocoumarins produced by their host plants, yet no species level phylogeny is available. This study is the only modern phylogeny of the genus, and includes all North American species but one, and about half the Old World species. In Chapter Six I describe nine new species of Scythris Hubner (Scythridinae) from the Galapagos Islands, Ecuador, and provide a key and illustration of genitalia and abdominal modifications. Finally, Chapter Seven represents an application of moth taxonomy to address questions of sampling protocols used for studies of biodiversity and conservation. I use Gelechioidea in eastern North America as indicators of diversity, with attention to the effectiveness of different sampling protocols with respect to active versus passive sampling, and plot-based versus plotless sa (open full item for complete abstract)

Committee: John Wenzel (Advisor) Subjects: Biology, Entomology

Doctor of Philosophy, The Ohio State University, 2004, Entomology

Spodoptera frugiperda (J. E. Smith), considered for a long time a generalist feeder, now is known to comprise two genetically differentiated host-associated strains, designated as corn strain (CS) and rice strain (RS). Previous studies have revealed that females attract males of both strains but mate almost exclusively with their own strain. Males are known to possess two sets of hairpencils (potential pheromone-producing structures), but their role has not been previously assessed. The species is a good model to test Phelan's (1992) Asymmetric Tracking model, which predicts that the sex with the greater parental investment will be more discriminating in their response to sexual signals, and that signals produced by the other sex will evolve to track this preference. Courtship sequences of S. frugiperda were videorecorded in an arena under infrared light, and analyzed frame by frame. Individual behaviors were transcribed to three-dimension transitional matrices, which were submitted to Information Theory analysis for quantification of intra- and inter-individual communication. Information analysis confirmed the existence of an asymmetry in the response between the sexes in S. frugiperda. In both intra- and inter-strain courtships, female-to-male information flow was lower than for male-to-female. Moreover, both RS and CS females were more likely to show a receptive response to male behaviors associated with hairpencil displays when courted by males of their own strain. These findings of a male-signal-based female preference for assortative mating, particularly in the absence of mate discrimination by males are consistent with the predictions of the Asymmetric Tracking hypothesis (Phelan, 1992) and the more specific hypothesis of Phelan and Baker (1987) that many lepidopteran male pheromones may have evolved in the context of reproductive isolation through sexual selection. Chemical characterization of each set of hairpencils was also conducted by solvent extraction (open full item for complete abstract)

Committee: P. Larry Phelan (Advisor) Subjects: Biology, Entomology

Master of Science, Miami University, 2006, Zoology

The spatial structure of a population is often determined solely by the frequency of interpatch movements. Landscape structural features and the behavioral response of organisms to these features affect animal movements among suitable habitat patches, but these factors have not been applied to spatial population studies. I recorded the movements, abundance, and behavioral response to the habitat edge of two species of butterflies, the great-spangled fritillary (Speyeria cybele) and the pearl crescent (Phyciodes tharos), among remnant prairie patches in south-central Ohio to determine the spatial structure of the populations and the mechanistic basis of movements among patches. The great-spangled fritillary exhibited characteristics of a patchy population because of the relatively high number of interpatch movements and its greater abundance at the patch edge. The pearl crescent moved infrequently among patches and was isolated within patches by the patch edge and all forest-matrix types, suggesting a classic metapopulation structure.

Committee: Thomas Crist (Advisor) Subjects: Biology, Ecology