Schedule at a Glance Speaker Index Room 1 Room 2 Room 3 Room 4 Room 5 Room 6 Room 7 Room 8 Room 9 Room 10 Room 11 Room 12 CAS Posters ASP Posters Special Events
Casearia Jacq. in Madagascar is in extreme need of taxonomic revision. We have identified three varieties of Casearia nigrescens Tul. that are endemic to small regions of Madagascar and that, by virtue of their different leaf shapes and other characteristics, clearly merit recognition at species level. Casearia onivensis (H. Perrier) Angelina X. Wang & Appleq. is endemic to mid-elevation humid forests in the Alaotra-Mangoro region; it is considered to be Data Deficient [DD] by IUCN criteria. Casearia subtrinervia (H. Perrier) Angelina X. Wang & Appleq. is endemic to a small area in the region of Analamazaotra; it is considered to be Endangered [EN B1ab(iii)+B2ab(iii)] by IUCN criteria. Casearia angustifructa Angelina X. Wang & Appleq. is a replacement name for C. nigrescens var. ovata H. Perrier. It is found in mid-elevation humid forests; it is considered to be Endangered [EN B2ab(iii)] by IUCN criteria.
Faculty Sponsor: Briana Lindh
Discipline: Biology
Many of Oregon's native bees have yet to be described by either their morphology, DNA or both. Through the work of the Oregon Bee Atlas, much progress has been made however many species are still not highly documented. One example is the species Melissodes Robustior, which has a recognized local (Willamette Valley) pollination pattern where females specialize in the Asteraceae family. This pattern has been documented locally in a couple of different counties throughout the state, however, this pattern has not previously been analyzed on a statewide level. By collaborating with the Oregon Bee Atlas, I investigate whether this pattern is consistent at the state level. What geographical and anthropogenic factors could affect this pattern? How does this knowledge help us further understand the past and future of Oregon native bee ecology?
Faculty Sponsor: Briana Lindh
Discipline: Biology
Endosymbionts are bacterial species that live inside of an organism's cells, and can have a range of effects on their host species. Wolbachia is a common endosymbiont of gall wasps and their parasitoids, and could be horizontally or vertically transferred between species . In order to better understand the relationship between gall wasps and parasitoids, and test for horizontal transmission, Wolbachia DNA was isolated from gall wasps and parasitoids using PCR. Successful PCR samples were sequenced and Wolbachia species were identified. Wolbachia was successfully identified in parasitoids from stem and leaf galls, but not successfully identified in gall wasps.
Faculty Sponsor: Chris Smith
Discipline: Biology
Many insects contribute to the cave ecosystem as food sources, predators, or decomposers. Little information is known about the animal life present within central Oregon caves. This research investigates the biodiversity of cave fauna within the Redmond Cave and Boyd Cave ecosystems in Bend, Oregon. Insects were collected from caves and sorted into 23 morphogroups. DNA was extracted from insects representing each morphogroup, and the cytochrome oxidase one barcoding gene was amplified by PCR and sequenced. Sequence data were compared to GenBank using BLAST to determine insect identities and to improve the understanding of these ecosystems.
Faculty Sponsor: Chris Smith
Discipline: Biology
To monitor changes in bee populations and make informed decisions about preservation there must be a baseline measurement of the species present in different regions. The genus Mellisodes is a widespread group of bees found across North America known to pollinate both native plants and agricultural crops. Due to the difficulty of identifying individuals in this genera using morphological characteristics, no comprehensive list of species present in Oregon currently exists. DNA Barcoding using the CO1 gene was performed to identify unknown species of Melissodes collected in Oregon and assess the suitability of traditional morphological identification techniques of species delimitation.
Faculty Sponsor: Chris Smith
Discipline: Biology
In 1918, eastern gray squirrels were introduced to Salem, OR, and are the most commonly introduced tree squirrel species in the world. Their prevalence and adaptability have become a threat to native squirrel and bird species. Since no other introduction of this species has been documented, but their non-native range encompasses much of the Pacific Northwest, the goal of this project was to identify how they have been dispersing and whether there have been multiple introductions Using microsatellites, population structure was determined using the software STRUCTURE. Genetic variation was compared between the introduced and the native ranges.
Faculty Sponsor: Chris Smith
Discipline: Biology
Joshua trees, Yucca brevifolia, are a keystone species of the Mojave desert. This region is especially impacted by climate change, and evidence suggests that the current range of Y. brevifolia has already been affected. One key element to modeling plant range is seed dispersal distance. Current research has determined average seed dispersal using radioactively marked seeds, but does not account for other factors which may impact the survivability and true dispersal distance. In this study, microsatellite data were used to determine distance between parents and offspring of Y. brevifolia (n=716) in Tikaboo Valley, Nevada.
Faculty Sponsor: Chris Smith
Discipline: Biology
Stem galls that grow on Quercus garryana trees in Oregon are induced by the cynipid wasp Andricus quercuscalifornicus and allow us to investigate multiple ecological relationships along with the effects of predation on the adaptive nature of galls. Many gall characteristics are productive in preventing predators, but little is known about the measures the cynipid wasp takes to prevent predation. I take a deeper look into cynipid wasp DNA to get a better understanding of the number of wasps that choose to lay their eggs in a single gall, and whether gall size plays a role in that decision.
Faculty Sponsor: Chris Smith
Discipline: Biology
This project is elucidating the function of the TonB Dependent Transporter CCNA_02910, predicted to transport cobalt, by assessing the effect of wildtype and mutant alleles on Caulobacter crescentus growth in different conditions. CCNA_02910 mutants show a distinct growth advantage in several types of normal, low cobalt, media, but show delayed culture growth upon media transition. Addition of 0.5 millimolar cobalt slows growth in both wildtype and mutant strains. Preliminary data also suggest that added cobalt appears to interfere with their successful exit from stationary phase. Together, our data suggest that CCNA_02910 is important in regulating Caulobacter stationary phase transition.
Faculty Sponsor: Melissa Marks
Discipline: Biology
Caulobacter crescentus live in and enhance productivity in aerobic, oligotrophic environments. When nutrients become scarce, bacteria can enter stationary phase. In this phase cell growth may stop, but the cell remains metabolically active. Bacteria are typically more stress resistant during stationary phase yet, they are still susceptible to stress associated with high oxygen utilization. Using a variety of techniques, I tested Caulobacter’s survival in environments with varied oxygenation. Together, my data suggest that cells experience lower rates of survival in higher oxygen environments, which may be due to oxidative stress.
Faculty Sponsor: Melissa Marks
Discipline: Biology
Polyethylene Terephthalate (PET) is the most common single-use plastic in the world, and the everyday production and distribution of plastic is adding to worldwide pollution. Microorganisms are adapting to degrade plastics that pollute their environments. We investigated microbial capabilities to degrade different PET plastic derivatives, using L-Asparagine, PET plastic, or low density polyethylene (LDPE), as carbon sources. A microbial consortium was inoculated into cultures consisting of a carbon free media along with the different plastic derivatives. We measured growth curves, and extracted RNA from samples to sequence genes involved in degradation.
Faculty Sponsor: Rosa Leon Zayas
Discipline: Biology