Life Sciences Commons^™

Adaptive Plasticity Of Coloration In Response To Environmental Change, Karissa Coffield

Scholars Week

When rapid environmental changes occur, different selective forces can create phenotypic trade-offs in which a trait can provide fitness benefits or costs under different environmental conditions. Amphibians are particularly vulnerable to environmental change, and previous research has revealed that some species will plastically respond to variation in temperature and ultra-violet radiation (UVR) by altering their coloration. Divergent selection on coloration may change with elevation and climate induced shifts in temperature because high temperatures are likely to result in lighter color morphs but as elevation increases, UVR exposure increases leading to the prediction that darker color morphs will be more common. …

Adaptive Plasticity Of Coloration In Response To Environmental Change, Karissa Coffield

Scholars Week

When rapid environmental changes occur, different selective forces can create phenotypic trade-offs in which a trait can provide fitness benefits or costs under different environmental conditions. Amphibians are particularly vulnerable to environmental change, and previous research has revealed that some species will plastically respond to variation in temperature and ultra-violet radiation (UVR) by altering their coloration. Divergent selection on coloration may change with elevation and climate induced shifts in temperature because high temperatures are likely to result in lighter color morphs but as elevation increases, UVR exposure increases leading to the prediction that darker color morphs will be more common. …

Evaluating Gizzard Shad Dorosoma Cepedianum Populations In Two Kentucky Reservoirs Recently Invaded With Silver Carp Hypopthalmichthys Molitrix, Nathan Klein

Scholars Week

Gizzard Shad Dorosoma cepedianum are an ecologically important fish species found in many reservoirs throughout the southeastern United States such as Kentucky Lake and Lake Barkley. One current challenge that Gizzard Shad may face in these two reservoirs is competition with the invasive Silver Carp Hypophthalmichthys molitrix. However, quantifying the impacts of this competition may be difficult because of limited baseline population data for Gizzard Shad in these two reservoirs. The objective of this study is to describe size structure, condition, age, growth, mortality, and spawning potential of these two populations. Gizzard Shad were collected by boat electrofishing and …

Assessing The Influence Of Urban Greening On Urban Arthropods, Brendon Lawrence

Scholars Week

Green Heart is an urban greening experiment in Louisville, KY seeking to create new urban green spaces to ultimately increase air quality and improve human health. Changes in biodiversity in response to urban greening may influence human health via multiple hypothesized pathways including reducing harm (e.g. medicine provisioning), restoring capacities (e.g. reductions in stress), building capacities (e.g. increasing activity outdoors), and causing harm (e.g. zoonotic diseases). Arthropods are one component of diversity that may influence human health via each of these pathways. However, few studies have assessed the influence of Arthropod diversity on human health. Thus, the objective of our …

Adaptive Plasticity Of Coloration In Response To Environmental Change, Karissa Coffield

Scholars Week

When rapid environmental changes occur, different selective forces can create phenotypic trade-offs in which a trait can provide fitness benefits or costs under different environmental conditions. Amphibians are particularly vulnerable to environmental change, and previous research has revealed that some species will plastically respond to variation in temperature and ultra-violet radiation (UVR) by altering their coloration. Divergent selection on coloration may change with elevation and climate induced shifts in temperature because high temperatures are likely to result in lighter color morphs but as elevation increases, UVR exposure increases leading to the prediction that darker color morphs will be more common. …

Using Modeling To Investigate Factors Driving Avian Diversity In Urban Ecosystems, Clay Bliznick

Scholars Week

Anthropogenic influences have altered global landscapes considerably throughout the past two centuries, resulting in the decline of natural land cover types. Conversely, land cover types such as cropland and urban areas that are derived from human activities have experienced vast expansion. This landscape transition has serious implications for ecosystem services. To mitigate the loss of these services, it is necessary to maintain ecological integrity within these anthropogenically-influenced systems. Being able to support high biodiversity is an indicator of well-functioning ecosystems, thus quantifying biodiversity and assessing its contributing factors can be useful for developing management strategies in artificial environments. Our objective …

Chlorophyll A And Primary Production Dynamics In Kentucky Lake: 2009-2018, Morgan Franklin

Scholars Week

Chlorophyll α (chl α) can be used as a proxy for phytoplankton biomass, while primary productivity (PP), the rate at which carbon is fixed into phytoplankton cells, is an indicator of how quickly carbon is turned over within the phytoplankton community. The purpose of this research was to examine the spatial distribution of chl α seasonally in Kentucky Lake and to examine the relationship between chl α and PP in two embayments of contrasting land use. The two sites analyzed are Ledbetter and Panther embayments. Data analysis showed that the chl α and PP were highly correlated; r=0.45 in Ledbetter …

The Piping Plover Problem: A Review Of Management Issues For A Threatened Shorebird, Andrew Lydeard, Gerry Harris

Scholars Week

Andrew Lydeard and Gerry Harris

The Piping Plover (Charadrius melodus) was federally listed in 1986. Since listing, Piping Plovers have been a focus of conservation and management efforts, particularly on their breeding grounds in the Northern Great Plains, Great Lakes, and northern Atlantic Coast. Despite management efforts that have resulted in range-wide population growth of the Piping Plover, growth in individual populations is often slow and reasons for this are poorly understood. A bias towards understanding drivers of declines on breeding sites compared to wintering and migratory stopover sites may be an underlying cause of this lack of …

Courtship Behavior, Communication, And Copulation In Tigrosa Annexa, Samuel White

Scholars Week

The evolution of multimodal communication, where signalers use multiple signal components in multiple sensory modalities, has become the subject of investigation by many researchers. Signaling puts males at risk of predation, so why do males of some species evolve extra signals that may increase this risk? In some wolf spider species, males incorporate many visual and vibrational signals into a display that they use to attract a female for mating. Female spiders are often aggressive toward courting males and so the male display also functions to decrease the odds of cannibalism. Female wandering spiders deposit silk containing pheromones that communicate …

Can Omnivores Mediate The Effects Of Degradation?, Hannah Moore

Scholars Week

Omnivores feed at multiple trophic levels and have large effects on community structuring and stability. The magnitude and direction of such effects, whether omnivores stabilize or destabilize communities, remains unresolved. Shifts in omnivore diet and trophic position may be of particular importance to community stability in degraded habitats, where resources are sparse. For example, omnivores may reduce the severity and duration of community responses to degradationby dampening the effects of any disturbance-mediated trophic cascade. The relatively simple food webs of freshwater systems are ideal for studying trophic ecology, and in the western U.S., streams are heavily degraded by overgrazing, beaver …

Examining The Relationship Between Climate And Seasonal Stream Thermal Regimes In A High Desert Ecosystem, Hannah Moore, Melody Feden

Scholars Week

Climate change is negatively affecting ecosystems around the world, and in the coming years, scientists predict that these changes will only intensify and accelerate. In the western mountains of North America, climate change projections predict elevated temperatures, reduced snowpack, and earlier snowmelt. Elevated air temperatures have the propensity to affect water temperatures in sensitive freshwater ecosystems. Temperature increases may cause streams to reach the upper thermal limit for many aquatic organisms, such as aquatic invertebrates and fish, and result in death or dispersal for these organisms. This makes the availability of cold-water refugia in streams that much more important for …

Can Omnivores Mediate The Effects Of Degradation?, Hannah Moore

Scholars Week

Omnivores feed at multiple trophic levels and have large effects on community structuring and stability. The magnitude and direction of such effects, whether omnivores stabilize or destabilize communities, remains unresolved. Shifts in omnivore diet and trophic position may be of particular importance to community stability in degraded habitats, where resources are sparse. For example, omnivores may reduce the severity and duration of community responses to degradationby dampening the effects of any disturbance-mediated trophic cascade. The relatively simple food webs of freshwater systems are ideal for studying trophic ecology, and in the western U.S., streams are heavily degraded by overgrazing, beaver …