Matching Items (5)
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- All Subjects: biodiversity
- Creators: School of Mathematical and Natural Sciences
Description
Virtually all animals require relatively predictable developmental schedules in order to fulfill the cycle of life. Cell death and severe inflammation alter steroid hormone production and can disrupt the timing of developmental transitions such as puberty. In the fruit fly, Drosophila melanogaster, injury to wing precursor tissues has been shown to result in decreased steroid hormone levels and delay development. The effects of damage to other tissues have not yet been explored. Here, the larval salivary glands were damaged in order to observe how injuring these specific tissues affect the timing of developmental transitions. Damage was induced by tissue-specific, temperature sensitive activation of cell death genes. The results indicated that death to salivary gland cells accelerates the Drosophila time to adult eclosion and that the observed acceleration of development is age-dependent. Insight into the effects of injury on development in Drosophila can potentially lead to information about development in other organisms, including humans, following injury or chronic inflammation.
ContributorsRippere, Alicia Leann (Author) / Hackney, Jennifer (Thesis director) / Marshall, Pamela (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Natural Sciences (Contributor)
Created2015-05
Description
As threats to Earth's biodiversity continue to evolve, an effective methodology to predict such threats is crucial to ensure the survival of living species. Organizations like the International Union for Conservation of Nature (IUCN) monitor the Earth's environmental networks to preserve the sanctity of terrestrial and marine life. The IUCN Red List of Threatened Species informs the conservation activities of governments as a world standard of species' risks of extinction. However, the IUCN's current methodology is, in some ways, inefficient given the immense volume of Earth's species and the laboriousness of its species' risk classification process. IUCN assessors can take years to classify a species' extinction risk, even as that species continues to decline. Therefore, to supplement the IUCN's classification process and thus bolster conservationist efforts for threatened species, a Random Forest model was constructed, trained on a group of fish species previously classified by the IUCN Red List. This Random Forest model both validates the IUCN Red List's classification method and offers a highly efficient, supplemental classification method for species' extinction risk. In addition, this Random Forest model is applicable to species with deficient data, which the IUCN Red List is otherwise unable to classify, thus engendering conservationist efforts for previously obscure species. Although this Random Forest model is built specifically for the trained fish species (Sparidae), the methodology can and should be extended to additional species.
ContributorsWoodyard, Megan (Author) / Broatch, Jennifer (Thesis director) / Polidoro, Beth (Committee member) / Mancenido, Michelle (Committee member) / School of Humanities, Arts, and Cultural Studies (Contributor) / School of Mathematical and Natural Sciences (Contributor) / College of Integrative Sciences and Arts (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
With increasing urbanization, organisms face a myriad of novel ecological challenges. While the eco-evolutionary dynamics of urbanization are currently receiving a great deal of attention, the effect of urban disturbance on the microbiome of urban organisms is relatively unstudied. Indeed, studies of the microbiome may illuminate the mechanisms by which some species thrive after urbanization (pest implications), while other species go locally extinct (biodiversity implications). We investigated the gut microbiome of the Western black widow spider (Latrodectus hesperus). L. hesperus is an ideal model system as they are a pest species of medical importance in urban ecosystems, often forming dense urban infestations relative to the sparse populations found in their native Sonoran Desert. To gain insight into the composition of the microbiome in L. hesperus and its potential function, we sampled 4 urban, 4 desert, and 2 laboratory-reared spiders, and high-throughput sequencing of the 16S rRNA V4 region was used to investigate the diversity of gut microbiota. Dominant bacterial phyla across all samples were Firmicutes, Proteobacteria, and Actinobacteria. While desert widows showed more gut microbial diversity than urban widows, the difference was not statistically significant. The relative abundance of taxonomic classes Blastocatellia, Acidobacteriia, and Thermoleophilia detected in desert spiders was especially higher than those in urban and laboratory-reared spiders. However, urban spiders had a higher relative abundance of taxonomic class Actinomycetia. Differences in widow gut microbiome diversity improves our understanding of how features unique to a habitat, like prey diversity and soil microbes, may be shaping their microbiome. Additionally, this work further highlights the impact urbanization has on biodiversity loss, which indirectly develops a new biomarker for differentiating between urban and desert black widow spiders based on their gut microbiome.
ContributorsAsrari, Hasti (Author) / Johnson, Chad (Thesis director) / Sandrin, Todd (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Natural Sciences (Contributor) / School of Life Sciences (Contributor)
Created2022-12
Description
Despite thousands of hectares of reforestation in Costa Rica, the landscape across the country remains fragmented by patches of large-scale commercial plantations and human communities. These patchy areas have a lack of suitable habitat and prey, meaning there is very little gene flow within meta populations of many mammal & predator species. This study aims to establish a baseline for mammal presence and diversity in the Las Tablas protected zone in order to better inform conservation and habitat restoration efforts. In a camera trap study conducted from January 2023 - May 2023, 37 non-baited cameras were placed across a study area of 328 square kilometers. Sites were selected using a stratified study design, with cameras deployed in forest, farm, and fragment habitat. A total of 839 independent videos captured 29 species of mammals and large-bodied ground birds from 10 different taxa. Videos were analyzed using the Sanderson Method (Harris et al. 2010), for relative abundance, naive occupancy, and absence-presence matrices. White-nosed coati (Nasua narica) had both the highest relative abundance and naive occupancy. Pearson’s correlation used to analyze the relationship between species richness at a site against camera effort as well as different landscape covariates (distance to national park border, distance to a riparian corridor, and patch size) showed effort and patch size to be the strongest predictor of a site’s richness. Shannon-weiner alpha diversity indices were calculated for the three different landscape types. Forest land types had the highest diversity indices while fragments had the lowest. This research provides a comprehensive baseline for mammal presence and diversity to better inform habitat restoration and jaguar conservation efforts in the Las Tablas region.
ContributorsDimas, Gabriela (Author) / Johnson, J. Chad (Thesis director) / Schipper, Jan (Committee member) / Ragan, Kinley (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Natural Sciences (Contributor) / College of Integrative Sciences and Arts (Contributor)
Created2024-05
Description
In an international field study, this project identified two primary objectives. The first was to familiarize the researcher with the environment, methods, and techniques used in the Costa Rica wildlife projects of ProCAT. After successful mastery of the first, the second objective was to use that knowledge to gather preliminary acoustic data in the southern region of Costa Rica. The data was analyzed for call type to identify species represented on the recordings. This information can be used to establish a 2024 baseline for avian diversity in these regions. An established baseline of biodiversity at a fixed timepoint enables effective and quantitative measures of change over time for future research and conservation.
ContributorsWalters, Jenna (Author) / Schipper, Jan (Thesis director) / Sellner, Erin (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Natural Sciences (Contributor)
Created2024-05