Dissertation Research: Ultrastructural Investigations of Fossil Gymnosperm Pollen and its Bearing on the Origins of Angiosperms

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The proposed research will involve the critical evaluation of pollen, primarily using transmission and scanning electron microscopy, from those gymnosperm groups suggested as closely related to angiosperms and implicated as possible ancestors. Only a paucity of data has been reported on pollen from the gymnospermous plants proposed to be investigated. A small database is currently in existence for dispersed gymnosperm pollen as well as pollen with possible angiosperm affinities. The proposed study, however, will principally address the nature of in site pollen grains from the various gymnosperm groups. Such a narrow focus, employing electron microscopic techniques, allows for the accumulations of significant data regarding specific pollen characters and provides the opportunity to perform phylogenetic analyses using many more characters from the specific taxa in question as well as to address numerous correlative and mechanistic queries concerning in situ pollen. Funds are requested to defray the costs of travel by the student investigator to two selected domestic paleobotanical collections of gymnosperms and one foreign collection in order to collect in situ specimens for investigation.