Phylogenetics an morphological diversification in capparaceae, cleomaceae, and brassicaceae

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Despite our fascination with the diversity of forms observed in flowering plants, our understanding of how this variation has arisen is limited.  The goal of my research is to better understand the mechanisms underlying differences in two key traits: fruit structure and floral symmetry.  A group within the mustard family, called the Brassiceae, is important because it includes crop species (e.g. canola, broccoli) and because the fruits are often segmented, a trait that dramatically alters how their seeds are dispersed.  The increasing importance of seed dispersal in crop plants and controlling the gene flow in genetically modified crop systems, and the increasing prevalence of introduced species in natural ecosystems, necessitate a detailed knowledge of fruit developmental genetics and evolution.  Species in the caper family reveal an impressive variation in floral form, including many changes in floral symmetry.  This trait has a significant impact on pollinator interactions including promoting speciation and diversification.Ultimately, we would like to know how changes in gene regulation have lead to morphology differences - a key question in biology.  We take a comprehensive approach that includes: (1) using DNA variation to elucidate relationships among morphologically distinct plants in order to understand transitions in form, (2) conducting detail developmental studies on a range of species to determine developmental patterns, (3) using molecular dating to determine the evolutionary timing of events, and (4) conducting genetic studies to examine how differences in gene expression may lead to morphological variation.  The two groups that I focus on, the Brassiceae and the capers, are both closely related to the genetic plant model, Arabidopsis, which will greatly facilitate genetic studies. Surprisingly, these groups have largely been overlooked with regards to improving our understanding of morphological diversity surrounding this important genetic model.