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Full-Text Articles in Life Sciences
Effects Of Environmental Heterogeneity In A Host-Parasite Coevolutionary Chase, Barry D. Derennaux
Effects Of Environmental Heterogeneity In A Host-Parasite Coevolutionary Chase, Barry D. Derennaux
Masters Theses
Species-species interactions are ubiquitous and it is thought that selection is very strong in many of these interactions, resulting in reciprocal evolution by natural selection. In antagonistic coevolution, one species benefits at the cost of another, resulting in a system where selection favors the strengthening of the interaction in one species, and acts to reduce the interaction in the other species. Previous theoretical work in homogeneous systems has identified a wide range of possible behaviors (including limit cycles, heteroclinic cycles, and equilibria) as well as explored how parameters effect local adaptation in species. Here we explore how heterogeneous systems and …
The Effects Of Treefall Gap Disturbances On Litter Ant Assemblages In A Tropical Montane Cloud Forest, Margaret Patrick
The Effects Of Treefall Gap Disturbances On Litter Ant Assemblages In A Tropical Montane Cloud Forest, Margaret Patrick
Masters Theses
In this study, we considered the effects of treefall gap disturbances on leaf litter ant assemblages in a Neotropical montane cloud forest. We asked a series of questions: (1) Do species richness, number of workers, and assemblage composition of leaf litter ants differ between treefall gaps and adjacent intact forests? (2) Do leaf litter ant assemblages become more similar to the assemblages in adjacent forest as gaps age? (3) What abiotic and biotic factors are correlated with ant species richness, and does the relative importance of these factors differ between gap and intact forest sites? To address these questions we …
Temporal Change Within And Among Forest Communities Of Great Smoky Mountains National Park: The Influence Of Historic Disturbance And Environmental Gradients, Windy A. Bunn
Masters Theses
Understanding how ecological communities change over time is critical for biodiversity conservation. However, few long-term studies directly address decadal-scale changes in the ecological communities of protected areas. In this study, we take advantage of a network of permanent forest plots, established in Great Smoky Mountains National Park in 1978, to investigate temporal changes in plant communities. In particular, we examine the factors that influence temporal change in species richness and composition within communities and temporal change in compositional similarity among communities. In 2007, we revisited 15 permanent plots that were logged in the late 1920s and 15 permanent plots that …
The Effects Of Prey Abundance And Bt (Bacillus Thuringiensis) Crops On Bat Activity In South-Central Texas Agroecosystems, Kimberly S. Kennard
The Effects Of Prey Abundance And Bt (Bacillus Thuringiensis) Crops On Bat Activity In South-Central Texas Agroecosystems, Kimberly S. Kennard
Masters Theses
Agroecosystems produce insects in great abundance, with episodic irruptions in time, and patchy distributions in space. In the industrial scale agroecosystems of south-central Texas, millions of Brazilian free-tailed bats (Tadarida brasiliensis) consume these insect pests. In the past decade, growers in Texas have planted transgenic Bt (Bacillus thuringiensis) crops on a large scale, which may reduce populations of target insect species by up to 95%. To investigate potential impacts of this evolving agricultural landscape on insectivorous bats, I examined the response of foraging bats to emergences of insects from replicate Bt and non-Bt fields of corn and cotton in the …