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- Title
- GENETIC AND PHENOTYPIC EVOLUTION IN THE ORNATE CHORUS FROG (PSEUDACRIS ORNATA): TESTING THE RELATIVE ROLES OF NATURAL SELECTION, MIGRATION, AND GENETIC DRIFT.
- Creator
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Degner, Jacob, Hoffman, Eric, University of Central Florida
- Abstract / Description
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Understanding how migration, genetic drift, and natural selection interact to maintain the genetic and phenotypic variation we observe in natural populations is a central goal of population genetics. Amphibians provide excellent model organisms for investigating the interplay between these evolutionary forces because amphibians are generally characterized by limited dispersal abilities, high philopatry, and are obligately associated with the areas around suitable habitats (e.g. breeding ponds...
Show moreUnderstanding how migration, genetic drift, and natural selection interact to maintain the genetic and phenotypic variation we observe in natural populations is a central goal of population genetics. Amphibians provide excellent model organisms for investigating the interplay between these evolutionary forces because amphibians are generally characterized by limited dispersal abilities, high philopatry, and are obligately associated with the areas around suitable habitats (e.g. breeding ponds). Thus, on relatively small geographic scales, the relative effects of all of these evolutionary forces can be studied together. Here, we study the interaction of migration, genetic drift, natural selection, and historical process in the ornate chorus frog (Pseudacris ornata). We report the development and characterization of 10 polymorphic microsatellite genetic markers. Number of alleles per locus ranged from 2 to 21 averaging 9.2 and expected heterozygosities ranged from 0.10 to 0.97 averaging 0.52. However, in an analysis of two populations, three locus-by-population comparisons exhibited significant heterozygote deficiencies and indicated that null alleles may be present some loci. Furthermore, we characterized genetic structure and historical biogeographic patterns in P. ornata using these microsatellite markers along with mitochondrial DNA sequence data. Our data indicate that in these frogs, migration may play a large role in determining population structure as pairwise estimates of FST were relatively small ranging from 0.04 to 0.12 (global FST = 0.083). Additionally, we observed an overall pattern of isolation-by-distance in neutral genetic markers across the species range. Moreover, our data suggest that the Apalachicola River basin does not impede gene flow in P. ornata as it does in many vertebrate taxa. Interestingly, we identified significant genetic structure between populations separated by only 6 km. However, this fine scale genetic structure was only present in the more urbanized of two widespread sampling localities. Finally, in this study, we demonstrated that there was a significant correlation between the frequency of green frogs and latitude. There was a higher frequency of green frogs in southern samples and a lower frequency of green frogs in northern samples. However, when we interpreted this phenotypic cline in light of the overall pattern of isolation-by-distance, it was apparent that the neutral evolutionary forces of genetic drift and migration could explain the cline, and the invocation of natural selection was not necessary.
Show less - Date Issued
- 2007
- Identifier
- CFE0001721, ucf:47319
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0001721
- Title
- LIGHTING DESIGN FOR FROM SUN TO SUN: A DAY IN A RAILROAD CAMP.
- Creator
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Szewczyk, Nathan, Scott, Bert, University of Central Florida
- Abstract / Description
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In this thesis the notion of a theoretical approach to the beginning stages of designing lighting for a theatrical production will be discussed. The topic being researched is: How a theoretical approach to entering the design process will enhance the final lighting design. The target audience for this study is theatrical lighting designers. A theoretical approach, in this case to the beginning of the design process, could be described as utilizing current dramatic theories to develop a better...
Show moreIn this thesis the notion of a theoretical approach to the beginning stages of designing lighting for a theatrical production will be discussed. The topic being researched is: How a theoretical approach to entering the design process will enhance the final lighting design. The target audience for this study is theatrical lighting designers. A theoretical approach, in this case to the beginning of the design process, could be described as utilizing current dramatic theories to develop a better understanding for the design of this production. In order to better understand this topic one would need to know how the process of lighting design is typically created and where the theoretical approach is implemented. An issue with this approach is that the short period allowed for the design process does not allow sufficient time to utilize a theoretical approach in a real world setting. A way of determining if this process is effective is through personal self review. Journaling and discussion with my advisor for this production will be the method of data collection. The method of validation will be a self reflection at the end of the final performance. An issue with the collection process is its reliance on personal opinions, including the author's. There are no ethical issues relating to this study. When applied, a theoretical approach to the design process will enhance the quality of the final lighting design through allowing the designer to be better prepared for a specific scene that he/she is struggling with.
Show less - Date Issued
- 2011
- Identifier
- CFE0003609, ucf:48874
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0003609
