Matching Items (3)
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- All Subjects: Native
- All Subjects: Rural
- Creators: Sweat, Ken
Description
The spread of urbanization leads to habitat fragmentation and deterioration and changes the composition of ecosystems for species all over the world. Different groups of organisms are impacted differently, and insects have experienced loss in diversity and abundance due to changing environmental factors. Here, I collected seed beetles across 12 urban and rural sites in Phoenix, Arizona, to analyze the effects of urbanization and habitat variation on beetle diversity and abundance. I found that urbanization, host tree origin, and environmental factors such as tree diversity and density had no impact on overall beetle diversity and abundance. Beetles were found to have higher density on hosts with a higher density of pods. In assessing individual beetle species, some beetles exhibited higher density in rural sites with native trees, and some were found more commonly on nonnative tree species. The observed differences in beetle density demonstrate the range of effects urbanization and environmental features can have on insect species. By studying ecosystem interactions alongside changing environments, we can better predict the role urbanization and human development can have on different organisms.
ContributorsPaduano, Gabrielle (Author) / Savalli, Udo (Thesis director) / Sweat, Ken (Committee member) / Division of Teacher Preparation (Contributor) / School of Mathematical and Natural Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Through the months September-November of 2017 a study was conducted to determine if bees prefer the sunflower, Helianthus annuus, native to Arizona, or a cultivar Helianthus sunflower in an urban environment. The study was executed in a small, controlled urban environment on Arizona State University West campus. Seven identified bee species and forty-nine specimens were collected, of the forty-nine specimens, two bees were reported on the Helianthus cultivar supporting native floral host preferences of native species. Variables such as nectar, pollen, floral color, and floral height were not measured, however, when the floral host genus was maintained wild bees visited the native Helianthus host significantly more yielding a supportive two-tailed p-value of 2.97x10-5. Three trends were identified in correlation with the experiment: 1) Bees foraged on native Helianthus annuus over the Helianthus cultivar, 2) Generalist species were more abundant than specialists on the Helianthus annuus, 3) Honey bees (Apis mellifera) were the most abundant species present. While not considered a trend, low floral diversity and abundance may explain the low diversity of bee species observed on the Helianthus. Floral host and pollinator desynchronization may also have affected bee diversity and abundance. Analysis of bee abundance and diversity support that wild bees may prefer native floral hosts over cultivar floral hosts when the floral genus, temperature, and time was controlled for in an urban environment.
ContributorsDunham, Jocelen Michaela (Author) / Foltz-Sweat, Jennifer (Thesis director) / Sweat, Ken (Committee member) / School of Mathematical and Natural Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-12
Description
One can argue that bees are the most unique insects in the animal kingdom due to their invaluable services they provide on a global level. Their importance goes beyond their capability of pollination; it is shown in their environmental impact and maintenance of the world's food supply. It is evident that the bee population is experiencing a serious and rapid decline that has resulted in changes to ecosystems in the past couple of decades. In order to resolve these issues, further research must be conducted to understand what humans can do to benefit their species' longevity. It is necessary for knowledge regarding bees, specifically their foraging behavior, to improve so humans can understand their essentiality to not only them, but the world. The focus of this study is to address any differences in foraging behavior between Apis mellifera, the honey bee, and native bee species. Other questions were answered including: do native and non-native bees have floral host preferences? Do native and non-native bees visit a variety of floral hosts? Experimental procedures were conducted to address these questions, which involved netting bees at differing times in four varying garden locations at the Desert Botanical Garden in Phoenix, Arizona. Then, the preparation of bee pollen and plant pollen slides along with bee mounting was performed. After the completion of data analysis, it was discovered that the preliminary data showed different foraging behavior between native and non-native bee species. Further studies are pertinent in obtaining statistically significant data due to an insufficient sample proportion. This is crucial in understanding the true differences in behaviors between both bee species.
ContributorsPerez, Czarinabelle Eunice (Author) / Foltz-Sweat, Jennifer (Thesis director) / Sweat, Ken (Committee member) / School of Social and Behavioral Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-12