Matching Items (3)
Filtering by
- Creators: School of Sustainability
- Member of: Barrett, The Honors College Thesis/Creative Project Collection
Description
Due to artificial selection, dogs have high levels of phenotypic diversity, yet, there appears to be low genetic diversity within individual breeds. Through their domestication from wolves, dogs have gone through a series of population bottlenecks, which has resulted in a reduction in genetic diversity, with a large amount of linkage disequilibrium and the persistence of deleterious mutations. This has led to an increased susceptibility to a multitude of diseases, including cancer. To study the effects of artificial selection and life history characteristics on the risk of cancer mortality, we collected cancer mortality data from four studies as well as the percent of heterozygosity, body size, lifespan and breed group for 201 dog breeds. We also collected specific types of cancer breeds were susceptible to and compared the dog cancer mortality patterns to the patterns observed in other mammals. We found a relationship between cancer mortality rate and heterozygosity, body size, lifespan as well as breed group. Higher levels of heterozygosity were also associated with longer lifespan. These results indicate larger breeds, such as Irish Water Spaniels, Flat-coated Retrievers and Bernese Mountain Dogs, are more susceptible to cancer, with lower heterozygosity and lifespan. These breeds are also more susceptible to sarcomas, as opposed to carcinomas in smaller breeds, such as Miniature Pinschers, Chihuahuas, and Pekingese. Other mammals show that larger and long-lived animals have decreased cancer mortality, however, within dog breeds, the opposite relationship is observed. These relationships could be due to the trade-off between cellular maintenance and growing fast and large, with higher expression of growth factors, such as IGF-1. This study further demonstrates the relationships between cancer mortality, heterozygosity, and life history traits and exhibits dogs as an important model organism for understanding the relationship between genetics and health.
ContributorsBalsley, Cassandra Sierra (Author) / Maley, Carlo (Thesis director) / Wynne, Clive (Committee member) / Tollis, Marc (Committee member) / School of Life Sciences (Contributor) / School of Human Evolution and Social Change (Contributor) / Barrett, The Honors College (Contributor)
Created2017-12
Description
Drylands cover almost half of the land surface on Earth, yet there is still little understood of the processes in these ecosystems. This project studied the impact of macroclimate (precipitation and temperature in large regions) in comparison to microclimate (the climate under canopy versus in the open) to learn more about the drivers of litter decomposition in drylands.
ContributorsMcGroarty, Megan (Author) / Throop, Heather (Thesis director) / Trembath-Reichert, Elizabeth (Committee member) / Reed, Sasha (Committee member) / Barrett, The Honors College (Contributor) / School of International Letters and Cultures (Contributor) / School of Earth and Space Exploration (Contributor) / School of Sustainability (Contributor)
Created2021-12
Description
Human activity produces ambient noise that potentially alters species’ abilities to communicate with each other—among other impacts. Given that birds are known to be sensitive to structural changes in habitat and highly communicative through sound, it is beneficial to understand how changing acoustic ecologies and ambient noise impact birds’ ability to communicate in their respective environments. In this study, mockingbird calls from an urban, desert, and intermediate study site were recorded and analyzed for differences in acoustic properties. Acoustic properties such as frequency and amplitude differed significantly across sites as it was determined that mockingbirds in urban areas increase both the peak frequency and amplitude of their calls in order to communicate. This study identifies what these changes in acoustic properties mean in relation to the survival and conservation of birds and concludes with recommendations for novel research.
ContributorsReynolds, Bailey Susana (Author) / Pearson, David (Thesis director) / Walters, Molina (Committee member) / School of Sustainability (Contributor) / School of Life Sciences (Contributor) / Dean, W.P. Carey School of Business (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05