REU: Pollen Morphology and Evolution in the Proteaceae

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The taxonomic classification of the southern hemisphere plant family Proteaceae, distributed in Australia, South Africa, and South America, is based largely upon morphological features of the flowers and fruits. About 67 genera and 1450 species are currently recognized. To test the classification of these plants with new data, Dr. Sylvia Feuer of DePaul University is investigating the pollen structure and sculpturing of representative samples using light- and electron-microscopy. Fine details of the pollen wall surface and wall layering are being analyzed with cryosections and with transmission electron microscopy, to obtain information useful in determining equivalent features for comparison among pollen from different genera. Patterns of pollen wall structure and sculpture are expected to be similar among closely related groups of taxa, and to exhibit recognizable trends of evolutionary change. Differences among pollen grains of this family that are being described by Dr. Feuer will also allow determination of the correct taxonomic association of dispersed fossil pollens. Grains thought to be from Proteaceae occur in deposits in the northern hemisphere, far outside the current geographic range of the family. Accurate determination of their taxonomic status is prerequisite to resolution of the historical biogeography of these plants and to further analysis of climatic and other controls on plant distribution.