Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 3 of 3
Full-Text Articles in Entire DC Network
Juvenile Ornamentation: Its Evolution, Genetic Basis, And Variation Across Habitats, Angela Tringali
Juvenile Ornamentation: Its Evolution, Genetic Basis, And Variation Across Habitats, Angela Tringali
Electronic Theses and Dissertations
Ornamental traits are considered honest advertisements of fitness, and their evolution is usually explained in terms of sexual selection. This explanation remains unsatisfactory in some instances, for example, juvenile birds whose plumage is molted prior to adulthood and breeding. I first evaluate whether juvenile plumage reflectance signals dominance status in the Federally Threatened Florida scrub-jay (Aphelocoma coerulescens) using a combination of observational and experimental methods. Then I estimate the heritability, non-genetic maternal and environmental effects, and strength of selection on juvenile plumage reflectance using archived feather samples and a pedigree constructed from historical nest records. Finally, I compare plumage reflectance …
Effects Of Isolation On Metapopulation Dynamics In Small-World Networks, Alaina Brooke Bernard
Effects Of Isolation On Metapopulation Dynamics In Small-World Networks, Alaina Brooke Bernard
Electronic Theses and Dissertations
Simulation models are valuable for making predictions that may be tested in natural systems and for understanding observed patterns. The simulation model developed for this thesis evaluates the effects of spatial network architecture, including organism dispersal patterns and isolation of habitats, on metapopulations. Two fields were merged throughout this project: metapopulation biology and small-world network theory. Small-world networks are characterized in their extremes as scale-free or single-scale. These models potentially simulate the networks of habitats and corridors in which metapopulations operate. Small-world network theory has been used to describe systems as diverse as rivers, the world-wide-web, and protein interactions, but …
Dispersal Behavior Of Mosquitofish (Gambusia Holbrooki), Shireen Alemadi
Dispersal Behavior Of Mosquitofish (Gambusia Holbrooki), Shireen Alemadi
Electronic Theses and Dissertations
Mosquitofish (Gambusia holbrooki) are native to the southeastern United States but invasive elsewhere, and are dominant predators in many ecosystems that they inhabit. Information on dispersal behavior will help better understand and predict mosquitofish metapopulation dynamics and invasions. I experimentally tested dispersal behavior of individual mosquitofish under a range of laboratory conditions relevant to field situations. Preliminary experiments showed that gender, lighting conditions, hunger and acclimation time did not significantly affect net dispersal rate. Power analysis based on this preliminary experiment determined that 6 replicate fish were sufficient for each subsequent experiment; I used 24 fish, and each fish was …