DISSERTATION RESEARCH: Phylogenetic Systematics and Biogeography of Iguanodontian Dinosaurs

禽龙属恐龙是一种多样的食草动物，从小型到大型都有。鸭嘴龙身长可达30英尺。这个群体持续了近1亿年，在每个现代大陆都有。禽龙的进化跨越了许多主要的解剖学界限，包括体型（从小到大）、运动方式（两足到四足）和摄食方式（小齿的割草机到有数百颗牙齿的植物加工机器）。为了理解这些进化变化，这项研究试图理解它们进化的多样化模式或系统发育。为此，将对所有已知禽龙物种的化石进行检查，以研究它们随时间变化的解剖结构。所有观察到的解剖变化的矩阵将被编译并使用计算机算法检查，以确定禽龙之间最可能的系统发育关系。这些进化关系将被用来研究它们随时间的地理分布。禽龙进化关系的假设将为研究它们的生物学提供一个框架，比如体型、运动和进食机制的变化。本研究还将测试在系统发育分析中包括仅从幼年标本中已知的物种的方法；这将有可能广泛应用于其他群体。最后，禽龙生物地理格局（时空演化）将有助于更好地理解中生代脊椎动物的生物地理格局。

Iguanodontian dinosaurs are a diverse group of herbivores that range from small to large ?duck-billed? hadrosaurs reaching 30 feet in length. The group persisted for nearly 100 million years and is known from every modern continent. The evolution of iguanodontians crossed many major anatomical boundaries, including those of size (small to huge), locomotion type (bipedal to quadrupedal), and feeding style (small-toothed croppers to plant-processing machines with hundreds of teeth). To make sense of these evolutionary changes this study seeks to understand the diversification pattern, or phylogeny, of their evolution. To this end, fossils of all known species of iguanodontians will be examined to study their changing anatomy through time. A matrix of all observed anatomical changes will be compiled and examined using computer algorithms to determine the most likely phylogenetic relationships among iguanodontians. The evolutionary relationships will then be used to examine their geographic distributions through time.A hypothesis of the evolutionary relationships of iguanodontians will create a framework to study their biology, such as changes in size, locomotion, and feeding mechanics. This study will also test methods for including species known only from juvenile specimens in the phylogenetic analysis; this will have potential widespread application to other groups. Finally, patterns in iguanodontian biogeography (evolution through time and space) will inform a better understanding of the biogeographic patterns of Mesozoic vertebrates.