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Ectotherm Thermoregulation At Fine Scales: Novel Methods Reveal A Link Between The Spatial Distribution Of Temperature And Habitat Quality, Ian Axsom

Master's Theses

Investigating ecological questions at the scale of individual organisms is necessary to understand and predict the biological consequences of environmental conditions. For small organisms this can be challenging because we need tools with the appropriate accuracy and resolution to record and quantify their ecological interactions. Unfortunately, many of our existing tools are only appropriate for medium to large organisms or those that are wide ranging, inhibiting our ability to investigate the ecology of small organisms at fine scales.

In Chapter 1, I tested a novel workflow for recording animal movements at very fine spatial and temporal scales. The workflow combined …

Population Genetics Of Cownose Rays, Rhinoptera Spp. In The Western Atlantic, Helen Weber

Master's Theses

Using molecular tools (e.g., the NADH subunit II mitochondrial gene), this study was the first to document the Brazilian cownose ray, Rhinoptera brasiliensis, within the northwestern Atlantic (NWA), and was the first study to examine population structure in R. brasiliensis within the NWA or northern Gulf of Mexico (GMX), revealing novel insights into the population biology of the animal and extending its range by nearly 1,500 km. This study also examined the sympatrically occurring American cownose ray, R. bonasus, and found population structure between the NWA and the GMX and the NWA and the southwestern Atlantic (SWA). High …

The Shallow Benthic Invertebrate Recovery From The End-Cretaceous Mass Extinction Across The Gulf Coastal Plain, Ronan B. Beltracchi

Master's Theses

The Gulf Coastal Plain, in the southeastern United States, contains several sites with well-preserved fossil assemblages from the Cretaceous- Paleogene boundary (K/Pg). Changes in benthic macroinvertebrate assemblages after mass extinction events commonly include reduction in body size of surviving organisms and preferential survival based on ecospace occupation. This study examines patterns of functional ecology and body size change in mollusk fossils from bulk samples collected throughout the post-extinction recovery interval at a well-studied boundary site from Darting Minnow Creek in Brazos, Texas USA and a recently described K/Pg boundary section on the Ouachita River in Malvern, Arkansas USA. The proportional …

The Modern-Day Effect Of Holc Redlining On Neighborhood Development, Liubov Ivashov

Master's Theses

Racial segregation, which happened more than one hundred years ago in the U.S., is a fundamental cause of economic inequality for people living in historically segregated neighborhoods today. Redlining was one form of federal policy that forced to separate communities by race even more after the Great Depression. The Home Owners Loan Corporation (HOLC) maps are widely used in economic research papers as one of the most comprehensive sources of data available to measure the effect of residential segregation. In this paper, using the Historical Redline Score (HRS) method, the author measured the association between modern-day population distribution, rent prices, …

Research Handling Effects On Stress Hormones, Blood Parameters, And Heart Rate In Juvenile Northern Elephant Seals (Mirounga Angustirostris), Lauren A. Cooley

Master's Theses

Wildlife researchers must balance the need to safely capture and handle their study animals to sample tissues, collect morphological measurements, and attach dataloggers while simultaneously ensuring their results are not confounded by stress artifacts caused by handling. To determine the physiological effects of research activities including chemical immobilization, transport, instrumentation with biologgers, and overnight holding on a model marine mammal species, I collected hormone, blood chemistry, hematology, and heart rate data from 19 juvenile northern elephant seals (Mirounga angustirostris) throughout a translocation experiment. Across my six sampling timepoints, cortisol and aldosterone data revealed a moderate hormonal stress response to handling …