Comparative and Evolutionary Physiology Commons^™

Impact Of Thermal-Hydric Stress Of Physiological Performance And Mating Behavior Of Fiddler Crabs, Talene G. Yeghissian

Dissertations

Fiddler crabs live on the edge of their thermal tolerance limits, balancing the need to thermoregulate with the need to mate. Previous research suggests that increased temperature reduces fiddler crab surface activity time, thus decreasing mating opportunities, throughout the range species with greatest impacts to low latitude populations. The less studied missed mating opportunities associated with behavioral compensation for thermal stress are crucial to understanding species vulnerability to climate change. In this dissertation, I describe a combination of experimental and observational approaches in the field and in the laboratory to investigate the physiological and behavioral responses of fiddler crabs to …

Characterization Of Andrenocortical Tissue Morphology, Histology, And Steroid Synthesis Among Finetooth (Carcharhinus Isodon), Blacktip (Carcharhinus Limbatus), Atlantic Sharpnose (Rhizoprionodon Terraenovae), And Bonnethead (Sphyrna Tiburo) Sharks, Danielle Elizabeth Bailey

Master's Theses

Adrenocortical (interrenal) tissue is composed of steroidogenic cells that produce corticosteroids involved in the stress response and hydromineral balance. Previous research characterizing the elasmobranch interrenal suggests that the number of interrenal bodies that produce the single primary corticosteroid, 1a-hydroxycorticosterone (1a-OHB), varies among species. However, potential species-specific differences in the amount of interrenal tissue and major steroid products produced have been understudied. To address this critical gap in our understanding of elasmobranch biology, this study examined interrenal morphology, cell structure, steroidogenic enzyme distribution (3bHSD), and steroid production in four shark species: Finetooth Carcharhinus isodon, Blacktip Carcharhinus limbatus, Atlantic Sharpnose …

Examining The Combined Effects Of Dissolved Oxygen, Temperature, And Body Size On The Physiological Responses Of A Model Macrobenthic Polychaete Species, Capitella Teleta, Kelsey Burns Gillam

Dissertations

While the scientific community is in consensus that coastal systems are threatened by climate change, few climate change studies test the effects of more than one variable directly related to climate change. The dissolved oxygen (DO) levels of the ocean are currently subject to both global warming and eutrophication; 94% of all hypoxia zones are expected to experience >2°C increase by 2035. This dissertation aims to examine how a model organism responds to simultaneous thermal and DO stress involving four levels of DO (100%, 70%, 50%, and 20%) saturation and three temperatures (15°C, 20°C, and 25°C).

The polychaete, Capitella teleta …