DISSERTATION RESEARCH: Morphological and Behavioral Evolution in Myrmecocystus

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Understanding the interplay of morphological and behavioral evolution with speciation and biogeographic differentiation remains one of the main tasks of biology. This requires well-supported phylogenies (evolutionary histories) of groups with relevant character variation and the use of biologically-informed models. This proposal will investigate such questions by testing predictions generated from evolutionary theory, focusing on honeypot ants (Myrmecocystus). These ants occur in arid regions of western North America and are especially noteworthy for their wide range of foraging times (some forage only in the heat of the desert day, while others will only forage at night, perishing quickly if outside the nest at daytime). The ants' evolutionary history will be inferred using multiple genes. Specimens will be measured for traits, such as leg length and eye size, which may have a major effect on the ants' ecology and behavior. Other information on ecology, behavior, and geographic range will be compiled from the literature, information in collections, and personal observation. Where needed, new models for character evolution will be developed and implemented in free, open-source, user-friendly computer programs so that other scientists may also use them. The tree, character information, and models will be used to test hypotheses and make inferences about evolution in this group. Hypotheses to test include predictions regarding the direction and rate of morphological character shifts as a result of changes in foraging time, ecological character displacement following range expansion after speciation, relative transition rates between foraging times, and the geography of speciation events. In addition to obtaining insights about the evolutionary biology of Myrmecocystus, this project will archive a variety of biological information in a web-accessible database and provide tutorials so that others can create similar websites using freely available tools such as MySQL and PERL. Preliminary efforts in this direction ( http://www.brianomeara.info/myrmecocystus ) have led to posting of interactive dichotomous keys generated on the fly using a relational database and PERL. For each species in Myrmecocystus a dynamic web page is now available that includes information on sequences available for that species in GenBank, links to other online information, and information about that species (such as suitable primer pairs for PCR or where the species can be found) returned from the project database. This allows other scientists to learn effective techniques from this project as they are discovered. Source code and instructions for converting paper keys to online keys, generating dynamic species pages, and using a relational database to manage a research project such as this will be written and posted.