Thesis (Ph. D.)--Texas A & M University, 2003. / "Major Subject: Entomology." Title from author supplied metadata (automated record created on Apr. 30, 2004.). Vita. Abstract. Includes bibliographical references.

Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2007. / Source: Dissertation Abstracts International, Volume: 68-07, Section: B, page: 4244. Adviser: Robert J. Novak. Includes bibliographical references. Available on microfilm from Pro Quest Information and Learning.

Thesis (M.S.)--Oklahoma State University, 2009. / Vita. Includes bibliographical references.

Thesis (Ph. D.)--Texas A & M University, 2003. / "Major Subject: Entomology." Title from author supplied metadata. Includes bibliographical references.

<p>Bees are essential for crop pollination services; however, the ecosystem services they provide by pollinating native plants are crucial for maintaining biodiversity in natural systems. This study analyzed bee community changes within, on the edge, and outside of forest fragments. Phenological variation over two seasons and modeling to predict bee abundance associated with forest characteristics was performed. Finally the genetic diversity of two species of Bombus was analyzed. Bowl traps and aerial sweep netting in and near forest patches were used to sample bee communities in northern Delaware between March and August, 2013 and 2014. Bee phenology stayed consistent between field seasons, but fewer bees were collected in 2014 compared to 2013. Abundance modeling (R: unmarked) predicted that bee abundance was negatively impacted primarily by agriculture surrounding the forest patch. Analyses using microsatellites revealed that B. impatiens lacked overt population genetic structure while B. bimaculatus showed two genetically distinct populations. Pesticide analysis revealed 17 pesticides observed on adult bees from seven urban and suburban forest patches. Further studies investigating natural bee fluctuations in response to multiple field seasons, floral diversity, and chronic pesticide exposure are crucial in order to assess native pollinator health.

Complex signaling, while common throughout the animal kingdom, is poorly understood and generally understudied. This dissertation provides a framework from which one can approach studies of complex signal function. The semantics involved in studies of signal evolution and complex signaling are discussed and complex signaling is broken down into two categories: multiple signals and multimodal signals. While single signals ultimately reflect the pressures of both tactical and strategic design, so must complex signals. I explore hypotheses relating to the function of complex signaling in terms of both tactical and strategic design pressures and then explore hypotheses allowing for the possibility of inter-signal interactions. Predictions of some tactical design hypotheses of complex signaling suggest that multimodal signals can act independently, as back-ups to each other in the presence of environmental noise, or they can interact in a variety of ways. I tested the tactical back-up hypothesis, among others, using the bimodal signaling wolf spider Schizocosa uetzi. Results suggest that the signals are not independent and that there is an inter-signal interaction in which the vibratory signal redirects and focuses a female's attention to the visual signal. A comparative approach explored the tactical and strategic design components of multimodal signaling across three species of Schizocosa, one unimodal signaling species (S. avida, vibration only) and two bimodally signaling species (S. uetzi and S. stridulans). Signal non-independence was found for both bimodally signaling species but the pattern of inter-signal interaction differed between the species. Inter-population interactions between divergent populations that possess independent, derived traits can also be affected by inter-signal interactions. Results from an empirical study using two divergent populations of the jumping spider Habronattus pugillis in inter-populational reciprocal crosses were compared to predictions of different models of sexual selection. Our results show a xenophilic mating preference with one population of females mating more frequently with foreign males than local males, while the second population of females showed no such difference. While this pattern is inconsistent with Fisherian selection and does not completely fit the predictions of pure sensory exploitation, it is completely consistent with one pattern predicted from a process of antagonistic coevolution.

<p> Field corn, <i>Zea mays</i> L., has been introduced to the market with pyramided <i>Bacillus thuringiensis</i> (Bt) corn technologies. These technologies reduce kernel damage from ear feeding caterpillar pests, including corn earworm, <i>Helicoverpa zea</i> (Boddie). The first generation Bt traits in field corn demonstrated limited activity on corn earworm feeding on grain in ears. The pyramided corn technologies have greater cumulative protein concentrations and improved expression throughout the plant, so these corn traits should provide an effective management tool against these pests. In addition, reduced kernel injury may also have a direct effect on physical grain quality. The results for this trial showed no relationship between number of damaged kernels and yield was observed for corn hybrid expressing the Herculex^&reg;, YieldGard^&reg;, or Genuity VT Triple Pro^&reg; technologies. A significant relationship between both damaged kernels and test weight and damaged kernels and aflatoxin concentrations was observed in two technologies.</p>

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