The potential for effects of livestock on Grant’s gazelle (Gazella granti) and Thomson’s gazelle (Gazella thomsonii) were evaluated within Osupuko and Olepolos Wildlife Sanctuaries in Southern Kenya. The high prevalence of tribal Maasai pastoralism in these sanctuaries often raises the question of whether wildlife habitats within the sanctuaries are suitable with continued livestock utilization. Jacob’s Index was used to identify habitat preferences of both gazelle and livestock, and average percentage of overgrazing and invasive plant species were used to assess the quality of the habitats. A Pianka’s Index was used to establish whether there was niche overlap between Grant’s gazelle and Thomson’s gazelle on one hand, and shoats and cattle on the other. Grant’s and Thomson’s gazelle preferred closed bushland, while shoats preferred shrubland and cattle had no particular preference. The overall habitat for both sanctuaries was 20% overgrazed and encroached by invasive plant species. Pianka’s Index revealed that the lowest niche overlap occurred between Grant’s gazelle and Thomson’s gazelle (0.50), while the highest overlap occurred for Grant’s gazelle and cattle (0.86). This study identifies the critical need to uphold the health of open bushland areas through livestock regulations and invasive plant eradication.

Our planet is getting hotter. As the environment warms, populations will experience a continuous range of intermediate, or progressively warmer, environments. If a population experiencing increasingly stressful (warmer) conditions lacks appropriate phenotypic plasticity (the ability of an organism to change its phenotype in response to changes in the environment) or access to more suitable habitats (the ability to migrate to a new location that has the same environment it is already adapted to), then genetic change may be the only way to avoid extinction. It is of great interest, therefore, to ask how populations and communities will evolve in response to increasing global temperatures. More specifically, does the rate of thermal change affect the specific adaptations a population will evolve? We are examining this question by evolving a lytic dsRNA bacteriophage of Pseudomonas syringae pathovar phaseolicola, Ï•6 Cystovirus, to become thermostable (able to survive high temperatures) under a variety of regimes that increase temperature at different rates (suddenly, moderately fast, and gradually) over the course of the experiment. We expect that different genetic pathways to thermostability may become available depending on whether the temperature is increased slowly or rapidly. The results of this experiment could provide key insights into how the environment constrains the available genetic pathways an organism can explore, and thus whether and how it can adapt in a warming environment.

Gene duplications are an important source of raw genetic material necessary for evolution and have been associated with the morphological diversification of flowers in angiosperms. In the model plant Arabidopsis thaliana, two B-class genes of the ABCE model of flower development are responsible for the development of petals and stamens. The floral quartet model proposes that in order to bind DNA, the protein products of these genes must form heterodimers with each other and tetramers with an E-class protein. Although the genetic basis of flower development is well characterized in Arabidopsis there are many angiosperms whose flowers differ morphologically. Analysis of the early diverging eudicot Thalictrum thalictroides, a member of the Ranunculaceae (butter-cup family), provides insight into the function of floral identity genes outside of the “core eudicots”. Unlike Arabidopsis, T. thalictroides lacks petals, but its sepals exhibit ectopic petaloidy, in that they are large and showy. In addition the B-class genes of T. thalictroides have undergone additional rounds of gene duplication resulting in four B-class genes, which are all expressed in sepals, a deviation from the classical ABCE model. We hypothesize that one or more of the B-class genes has functionally diverged and may have acquired a role related to petaloidy of sepals. If this is the case, this morphological feature may be the direct result of the T. thalictroides B-class proteins interacting in novel ways. In order to elucidate the protein-protein interaction of the B-class genes we used a Yeast-Two Hybrid assay to characterize the ability of each B-class protein to form homo- and heterodimers among themselves and with the E-class proteins. Ongoing complementary targeted gene silencing experiments will provide functional insight of the B-class genes and whether they are involved in ectopic petaloidy, as well as contribute to our understanding of morphological diversity produced by gene duplications.

Spontaneous neural activity (SA) during brain development has been implicated in processes ranging from alteration of gene expression to development of neural networks that ready the newborn for post-natal life. Though SA is a well-known phenomenon, the mechanisms that dictate its expression, as well as its role(s) in developing circuits, are not well understood. SA is strongly expressed in the mouse brainstem from embryonic day (E) 10.5-13.5, with day-to-day changes in activity patterns. Our lab has investigated physiological properties of the midline cells participating in SA over the course of these changes and is now examining the characteristics of serotonergic (5-HT) and dopaminergic (DA) cells, which develop in close spatial and temporal proximity to midline SA. My project asks what physiological changes occur in the 5-HT and DA cells during the period of SA, and how they may be influencing or influenced by neural activity. To explore this I am performing visually guided whole-cell patch-clamp experiments in transgenic mice that allow for live targeting of neurons in the 5-HT or DA lineages, enabling us to compare cells I record from to well-characterized midline cells. In addition, I have been developing a tissue culture protocol that will let us pharmacologically manipulate particular cell types or a specific tissue’s ability to express SA so we can subsequently assess the changes in cell lineage development or brainstem activity patterns. These experiments will provide insight into the relationship between SA and 5-HT/DA neurons in the context of neural circuit development. An understanding of these processes is important for pinpointing how conditions like Parkinson’s Disorder, depression, and addictive behavior may arise.

Erosion and stormwater runoff are two major issues that will continue to plague us as climate change and our population continue to grow. Such issues are multifaceted problems that do not have simple or inexpensive solutions. Rain gardens are a low cost, simple development that can be used to collect rain water and reduce stormwater's velocity, which in turn reduces the amount of erosion. This project will evaluate the effectiveness of rain gardens used as a stormwater management technique. In order to do so, a baseline set of stormwater runoff and erosion data will be collected. A rain garden will be developed in the area, placed where it will have the highest impact in obstructing the runoff. Finally stormwater and erosion data will be collected again from downstream of the raingarden to test the effectiveness of the technique. With the introduction of a rain garden we expect to find decreased amounts of erosion and stormwater runoff. If it is the case that this project finds rain gardens to be a management technique for stormwater and erosion reduction, then this could help reduce costs in stormwater management.