Diversification in plant feeding insects : patterns of host-plant specialization and mating signal evolution inferred from species-level phylogeny and population genetics

The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file.Title from PDF of title page (University of Missouri--Columbia, viewed on March 29, 2010).Thesis advisor: Dr. Reginald B. Cocroft.Vita.Ph. D. University of Missouri-Columba, 2009.[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] Speciation yields two reproductively isolated groups capable of living in sympatry without cross-fertilization. Thi inability to hybridize is caused reproductive isolation before or after mating. Howeer, pre-mating isolation, total lack of post-mating isolation. Here I investigate the role of two forms of pre-mating isolating barriers (ecological and behavioral) in the promotion and maintenance of species boundaries. Using species level phylogenies and population genetics I have shown that ecological (host shifting) and behavioral (sexual communication) reproductive barriers are actively reducing the potential for hybridization in E. binotata species. This is the first study to isolate the role of behavioral isolation this model system for studying ecological (sympatric) speciation. Comparative studies of signal evolution, in the katydid Neoconcephals suggest that communication traits are subject rapid to parallel evolution, which may be influenced by an ecological actor, yet to be indentified.Includes bibliographical references