Life Sciences Commons^™

What Are The Impacts Of Deer Browsing And Japanese Stiltgrass (Microstegium Vinenium) On Native Sapling Growth In A Residential Wetland In Southeastern Georgia?, Josie Richards

Honors College Theses

Wetlands promote biodiversity, act as climate stabilizers, and regulate water flow, yet are vulnerable to invaders. An invasive species can affect the biodiversity, abiotic conditions, and increase vulnerability of an ecosystem over time and deer browsing can actively affect new growth by removing the apical buds of young woody vegetation. Japanese stiltgrass (Microstegium vimineum), a wetland specific invader, has been shown to compete against native species for limited resources and actively crowd them out. Growth of native saplings can be further complicated by the presence of white tailed deer (Odocoileus virginianus), which browse woody vegetation and limit recruitment of trees. …

Dna Methylation And The Response To Infection In Introduced House Sparrows, Melanie Gibson

Electronic Theses and Dissertations

Epigenetics is the study of molecular modification of a genome without changing its base pairs. The most studied type of epigenetic mechanism is DNA methylation, which is capable of turning a gene “on” or “off.” Epigenetic potential is the capacity to which an individual can have methylation on its genome. The more CpGs available, the greater the epigenetic potential. In invasive species, genetic variation has been observed to be paradoxical: not much of it exists on a genomic level, but epigenetically, phenotypic variation can occur. The focus on shift in gene expression in this study is on Toll-Like Receptor 4 …

Behavior And Chemical Signals As Markers Of Colony Identification In Argentine Ants (Linepithema Humile), Stephanie A. Rohrbach

Electronic Theses and Dissertations

Argentine ants, Linepithema humile, are a highly successful invasive species around the globe and are especially prominent in states such as California and the southeastern United States. L.humile have a unique form of unicoloniality, called “supercolonies”. L. humile can detect colonymates through scent markers in their outer cuticle. With these chemical markers, ants will exhibit high aggression if they smell different from one another. In our study, we performed aggression assays among ten different nest sites and analyzed their CHCs through gas chromatography mass spectrometry, or GC-MS, analysis. For our behavior results, while within-nest interactions displayed low aggression as …

The Mechanical Development For An Autonomous Forest Service Robot, James P. Walker

Honors College Theses

Georgia’s forests are under threat from numerous invasive species of plant, both herbaceous and woody. A primary factor in the invasive potential of any given non-native plant is the lack of natural predators and rapid reseed and regrowth cycles. To combat invasive plants, this thesis proposes an artificial, robotic predator to provide a means of controlling invasive species. Although autonomous robots are currently being developed for similar agricultural purposes, none have emerged for forestry related tasks, such as proposed in this work. The chassis, inspired by rocker bogie and similar suspension systems, has been redesigned to have eight wheels, to …

Determining The Reproductive Patterns Of The Titan Acorn Barnacle (Megabalanus Coccopoma) In Its Introduced Range, Isabel L. Moran Ms.

Honors College Theses

Invasive species are a significant conservation concern given their contribution to native species decline. The barnacle, Megabalanus coccopoma, is a common invasive species in tropical and subtropical regions of both the Pacific and Atlantic oceans. Little is known about the life history and ecology of M. coccopoma, and data on reproductive biology could provide valuable insight into its propensity to establish introduced populations. Most species of barnacle (including M. coccopoma) are hermaphroditic, but self-fertilization is rare in species studied to date. A recent genetic study of introduced M. coccopoma populations in the southeastern US showed high levels of …

Assessing The Genetic Status And Factors Leading To The Decline Of The Roanoke Bass (Ambloplites Cavifrons), Jackman C. Eschenroeder

Electronic Theses and Dissertations

Although numerous factors have led to the staggering declines in freshwater biodiversity throughout the United States and the world, habitat alteration and introduced species pose some of the greatest challenges to conservation efforts. Learning more about how these two factors lead to the decline of an endemic organism could help prevent the future loss of unique species and the premature conclusion of evolutionary trajectories. Roanoke bass (Ambloplites cavifrons) is a sport fish endemic to portions of the Roanoke, Chowan, Tar, and Neuse river basins of North Carolina and Virginia. This species has been in decline for many years, …

Relative Abundances Of The Recently Introduced Barnacles, Megabalanus Coccopoma And An Unidentified Species Of Megabalanus, In The Southeastern U.S., Jennifer L. Tyson

Honors College Theses

ABSTRACT

Megabalanus coccopoma is a prominent invasive species off the coast of Georgia. Recently, among collected samples thought to be M. coccopoma, several individuals of an unidentified species of barnacle were found. The species has been identified as a Megabalanus species, but is still unidentified to the species level. Species identification is difficult due to morphological variation, inconsistent taxonomic keys, and unknown origin. In this study I developed a method to accurately distinguish M. coccopoma from the unidentified Megabalanus sp. using sequence differences in the mitochondrial Cytochrome Oxidase I (COI) gene. This study will provide an accurate estimate of …