Ecology and Evolutionary Biology Commons^™

Gynodioecy And Biotic Interactions: Plant Traits, Insect Preferences, And Population-Level Consequences, Laura A. D. Doubleday

Doctoral Dissertations

In species with distinct sexes, differences between the sexes often affect interspecific interactions. In gynodioecious flowering plants, where individuals are female or hermaphrodite, both pollinators and herbivores tend to prefer hermaphrodites. Because pollinators and herbivores affect plant fitness, their preferences have consequences for plant mating patterns, natural selection on mating-related traits, and plant breeding system evolution. Being sessile, the spatial arrangement of females and hermaphrodites in gynodioecious plant populations alters conspecific density and sex ratio locally, which can also have important fitness effects. My dissertation combines observational studies in natural Silene vulgaris populations and simulation modeling to address questions about …

Pollination, Herbivory, And Habitat Fragmentation: Their Effects On The Reproductive Fitness Of Angadenia Berteroi, A Native Perennial Plant Of The South Florida Pine Rocklands, Beyte Barrios Roque

FIU Electronic Theses and Dissertations

Angadenia berteroi is a tropical perennial subshrub of the pine rocklands with large yellow flowers that set very few fruits. My dissertation seeks to elucidate the factors that affect the reproductive fitness of Angadenia berteroi a native species of the south Florida pine rocklands. I provide novel information on the pollination biology of this native species. I also assess the effects of herbivory on growth and the reproductive success of A. berteroi. Finally, I elucidate how habitat fragmentation and quality are correlated with reproductive fitness of this native perennial plant.

Using a novel experimental approach, I determined the most effective …

Modeling Simultaneous Selection For Resistance And Tolerance In Goldenrod (Solidago Altissima) Across A Range Of Spittlebug Population Densities, Michael J. Wise, Warren G. Abrahamson Ii

Warren G. Abrahamson, II

Plant defenses against herbivory include two main strategies: resistance (to minimize the amount of damage) and tolerance (to minimize the fitness impact of that damage). Recent studies have emphasized the need to consider both strategies simultaneously for a fuller understanding of the evolutionary and ecological dynamics of plant defense against herbivores. We used a combination of a garden study, a greenhouse experiment, and mathematical modeling to investigate resistance to and tolerance of spittlebug damage in the goldenrod Solidago altissima. In contrast to traditional expectations, the genetic correlation between resistance and tolerance was highly positive. Selection gradients indicated that directional selection …