Phylogenetics an morphological diversification in capparaceae, cleomaceae, and brassicaceae

尽管我们对在开花植物中观察到的形式的多样性着迷，但我们对这种变异是如何产生的理解是有限的。我研究的目标是更好地了解在两个关键特征上存在差异的机制：果实结构和花的对称性。芥菜科中一个被称为油菜科的类群很重要，因为它包括作物物种(例如油菜、西兰花)，而且水果通常是分段的，这一特征极大地改变了它们的种子传播方式。随着种子在作物中的传播和控制转基因作物系统中的基因流动的日益重要，以及自然生态系统中引入物种的日益普遍，有必要对果实发育遗传学和进化有详细的了解。山杏属植物在花型上表现出令人印象深刻的变化，包括花朵对称性的许多变化。这一特征对传粉者的相互作用有重大影响，包括促进物种形成和多样化。最终，我们想知道基因调控的变化如何导致形态差异--这是生物学中的一个关键问题。我们采取了一种综合的方法，包括：(1)使用DNA变异来阐明形态上不同的植物之间的关系，以了解形态的转变，(2)对一系列物种进行详细的发育研究，以确定发育模式，(3)使用分子测年来确定事件的进化时间，以及(4)进行遗传研究，以考察基因表达的差异如何导致形态变化。在我关注的两个群体中，油菜亚科和山杏都与遗传植物模型拟南芥密切相关，这将极大地促进遗传研究。令人惊讶的是，在改善我们对围绕这一重要遗传模型的形态多样性的理解方面，这些群体在很大程度上被忽视了。

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.