Life Sciences Commons^™

Changes In The Zooplankton Community In Barren River Lake (South Central Ky) Between 2008 And 2020, Laurel Philpott

Mahurin Honors College Capstone Experience/Thesis Projects

Zooplankton are small aquatic animals that serve an important role in transferring energy from phytoplankton to higher trophic levels. The zooplankton community composition in Barren River Lake from 2008 and 2020 was compared. A field study was conducted to not only describe the seasonal population dynamics of zooplankton in Barren River Lake, but also to determine if an invasive zooplankton, Daphnia lumholtzi, was present. While D. lumholtzi was found throughout Barren River Lake in 2008, it was absent from both resampled sites in 2019 and 2020. This, along with erratic patterns of emergence in several other zooplankton species, indicates …

Analysis Of Population Structure In A California Newt (Taricha Torosa) Metapopulation, Jessica Vincent

Mahurin Honors College Capstone Experience/Thesis Projects

As anthropogenic influences take an ever-increasing toll on the environment, understanding how environmental change affects species is paramount. Concern regarding decline in amphibian populations has spurred research examining the effects of habitat change on the dynamics of populations at landscape levels. One important goal is to understand how gene flow among populations is affected by changes in habitat. Biologists need to consider the relationship between gene flow and habitat alterations so that movements among individual breeding ponds can be maintained over time, reducing risk of local extinction events. This study focuses on patterns of gene flow among thirteen populations of …

Non-Adaptive Phentypic Plasticity: Morphology, But Not Swim Speed, Of Spotted Salamander Larvae Is Affected By "Terrestrial" And "Aquatic" Herbicides, Mitchell Schooler

Mahurin Honors College Capstone Experience/Thesis Projects

1. Phenotypic plasticity, although ubiquitous, may not always be advantageous. In cases where individuals expressing an induced phenotype outperform non-induced individuals, the phenotypic plasticity is considered adaptive. Conversely, if the individuals with an induced phenotype underperform relative to non-induced individuals, then the plasticity is maladaptive. A final possibility is that both induced and non-induced individuals perform equally well (or poorly). This would be a case of non-adaptive (i.e. neutral) phenotypic plasticity.
2. We investigated the mode of phenotypic plasticity induced by four glyphosate-based herbicides in larvae of the spotted salamander, Ambystoma maculatum (Shaw, 1802), by determining whether the herbicides induced different morphologies, …

The Ecological Roles Of Podostemum Ceratophyllum And Cladophora In The Habitat And Dietary Preferences Of The Riverine Caddisfly Hydropsyche Simulans, Brenna Tinsley

Mahurin Honors College Capstone Experience/Thesis Projects

The net-spinning caddisfly Hydropsyche simulans can be a common inhabitant of shallow reaches in riverine systems, and is easily the most common hydropsychid in the upper Green River, Kentucky. This study was performed in summer 2011 and focused on two main questions: 1. Do the larvae of the riverine caddisflies H. simulans and Cheumatopsyche preferentially inhabit dense patches of P. ceratophyllum compared to bare substrates in the upper Green River?, and 2. Do larvae of H. simulans and Cheumatopsyche consume the filamentous alga Cladophora during the annual late summer algal bloom in the upper Green River? Densities of both hydropsychid …