The Evolutionary Radiation of the Diplograptacea (Graptoloidea)

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Graptolites were marine colonial invertebrates that floated in the world's oceans during Paleozoic time. Their flattened remains are common in grey shales of this age, and they are important stratigraphic age indicators. Dr. Charles Mitchell proposes to collect and study graptolites that are preserved as unflattened specimens in limestones. These collections will reveal the intricacies of how the individuals grew and budded to form colonies. Dr. Mitchell will use a computer-based image analysis system in a quantitative study of morphology and growth. These analyses will be combined with a cladistic analysis of evolutionary relationships, resulting in a clearer picture of the early evolution of this important fossil group. The proposed research represents an ambitious and very modern study of an important fossil group by a young investigator. The project will help to establish procedures for combining morphometric studies with phylogenetic analysis, and it has potential for far-reaching impact on the study of colonial groups in general.