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Cross-Life Stage Effects Of Aquatic Larval Density And Terrestrial Moisture On Growth And Corticosterone In The Spotted Salamander, Julie F. Charbonnier, Jacquelyn Pearlmutter, James R. Vonesh, Caitlin R. Gabor, Zachery R. Forsburg, Kristine L. Grayson

Biology Faculty Publications

For organisms with complex life cycles, conditions experienced during early life stages may constrain later growth and survival. Conversely, compensatory mechanisms may attenuate negative effects from early life stages. We used the spotted salamander, Ambystoma maculatum, to test how aquatic larval density and terrestrial moisture influence juvenile growth, food intake, evaporative water loss and water reuptake rates, and corticosterone levels. We conducted an outdoor mesocosm experiment to manipulate larval density and transferred metamorphosed salamanders into low and high terrestrial moisture treatments in laboratory terrariums. After the larval stage, high-density salamanders were significantly smaller and had higher corticosterone release rates …

Thermal Physiology And Developmental Plasticity Of Pigmentation In The Harlequin Bug (Hemiptera: Pentatomidae), Carly D. Sibilia, Kelly A. Brosko, Christopher J. Hickling, Lily M. Thompson, Kristine L. Grayson, Jennifer R. Olson

Biology Faculty Publications

Traits that promote the maintenance of body temperatures within an optimal range provide advantages to ectothermic species. Pigmentation plasticity is found in many insects and enhances thermoregulatory potential as increased melanization can result in greater heat retention. The thermal melanism hypothesis predicts that species with developmental plasticity will have darker pigmentation in colder environments, which can be an important adaptation for temperate species experiencing seasonal variation in climate. The harlequin bug (Murgantia histrionica, Hemiptera: Pentatomidae, Hahn 1834) is a widespread invasive crop pest with variable patterning where developmental plasticity in melanization could affect performance. To investigate the impact of temperature …

The Neotropical Genus Austrolebias: An Emerging Model Of Annual Killifishes, Nibia Berois, María J. Arezo, Rafael O. De Sá

Biology Faculty Publications

Annual fishes are found in both Africa and South America occupying ephemeral ponds that dried seasonally. Neotropical annual fishes are members of the family Rivulidae that consist of both annual and non-annual fishes. Annual species are characterized by a prolonged embryonic development and a relatively short adult life.

Males and females show striking sexual dimorphisms, complex courtship, and mating behaviors. The prolonged embryonic stage has several traits including embryos that are resistant to desiccation and undergo up to three reversible developmental arrests until hatching. These unique developmental adaptations are closely related to the annual fish life cycle and are the …

The Exploration Of Novel Symbiotic Bacteria That May Have Influential Roles In Sponge Life History, Brittany E. West

Honors Theses

Sponges produce an impressive variety of secondary metabolites that perform a variety of ecological functions. Many marine sponges even harbor diverse carotenoid compounds, an unusual class of secondary metabolites that animals are incapable of producing. Furthermore, sponges serve as hosts to an astonishingly diverse microbial community that can occupy up to sixty percent of a sponge's biomass. Our research ultimately hopes to link microbial species to the production of secondary compounds, like carotenoids, and to assess the ecological role of such compounds and their effect on sponge life history strategy. This study describes the ecological distribution of two species of …

The Effect Of Thyroid Hormone On The Expression Of A7 Myosin Heavy Chain Mrna In Xenopus Laevis, Bradley Thomas Butkovich

Master's Theses

It has long been known that thyroid hormone (TH) is responsible for metamorphosis in tadpoles. It is also known that A7 MHC, an adult muscle isoform, is expressed in adult Xenopus laevis frogs, but not in larvae. Furthermore, the appearance of A7 corresponds with the onset of metamorphosis. The present study investigated the relationship between TH and the expression of A7 MHC mRNA in Xenopus laevis. Isolated tails in culture and 6-n-propyl 2-thiouracil (PTU) treated tails were treated with TH and the presence of A7 mRNA analyzed with in-situ hybridization, and RT-PCR. It was found that TH caused substantial …

The Effects Of Thyroid Hormone On Myosin Heavy Chain A-7 Production In Xenopus Laevis Tail And Leg Muscles, Andrew R. Noble

Honors Theses

The present research examines the expression of myosin heavy chain genes in muscle fibers in Xenopus laevis. Characteristically different muscle fibers are expressed before and after metamorphosis. The embryonic myosin proteins that are synthesized during the tadpole stages are replaced with adult myosin heavy chains at metamorphosis. At least one of the adult myosin genes, called A-7, is expressed only in the adult animals, not in tadpoles. The controlling factor or trigger for the expression of this adult gene still remains unknown. There are a number of possible explanations for the A-7 regulation at metamorphosis, including changes in particular hormone …

Some Factors Involved In Growth And Sporulation Of Pilobolus Crystallinus Tode And Pilobolus Umbonatus Buller, Kenneth L. Poff

Master's Theses

Pilobolus umbonatus Buller and P. crystallinus Tode grew normally in a nitrogen atmosphere but their sporagnia were non-pigmented. When palced in anaerobic jars along with obligately anaerobic and obligately aerobic bacteria, the fungi grew in the range of oxygen concentrations too low for growth of the aerobic bacterium, but high enough to prevent growth of the anaerobe. The fungi did not grow when the oxygen was depleted to the point that allowed growth of the anaerobic bacterium. Catalase was not produced by the hyphae and trophocysts which normally grow beneath the surface of the medium, but was present in the …