Kathleen B. Pigg
My research centers on integrating the plant fossil record with extant morphological and molecular data to better understand phylogeny, biogeography and character evolution in selected families of ferns and flowering plants. Exceptionally preserved fossils that provide detailed floral and fruit structure and often anatomical preservation are used to maximize taxonomic characters that can be compared closely to those of living relatives. Currently, I am studying floras from three different sources: the late Paleocene of North Dakota, the middle Eocene of Washington and adjacent Canada, and the middle Miocene of Washington. These three floras provide fossil evidence to address significant questions in plant evolution, diversification and biogeography. The Almont flora contains the only known Paleocene-aged plants with anatomical structure, and provides unique details about the early coryloid Betulaceae (hazelnuts), the oldest record of maples (Acer) and dogwoods (Cornus) and early evidence for the herbaceous buttercup family Ranunculaceae. The Eocene Okanogan Highlands floras document the early radiation of many temperate families such as the Rosaceae, which become dominant in the later, cooler and drier conditions of the Neogene. The middle Miocene Yakima Canyon flora documents the "last gasp" of a widespread temperate deciduous forest that includes many plants with disjunct Asian/southeastern North American distributions today, such as the sweet gum Liquidambar and the chain fern Woodwardia. This flora also provides evidence of plant/animal interactions such as oak/cynipid wasp gall/fungal interactions, and fossil dung from conifer needle-eating caterpillars.
Other research includes the study of Glossopteris, a dominant Southern Hemisphere plant of Permian age. Last year (Nishida, et al. 2003) we documented the presence of flagellated sperm, considered basal in seed plants, in this interesting gymnosperm. I also have an ongoing interest in the evolution of isoetalean lycopods, a group that evolved separately from the rest of the vascular plants at an early stage in land plant evolution, and have a rich fossil record that documents their independent achievement of such evolutionary grades as arborescence and seed-like reproduction. Lycopods are inconspicuous today, yet they successfully occupy aquatic niches similar to those of their coal-forming ancestors. My teaching interests include evolutionary, structural, and economic aspects of plant biology.
Selected Publications
Pigg, KB, SR Manchester, and ML DeVore. 2008. Fruits of Icacinaceae from the Late Paleocene of western North America. American Journal of Botany 95: 824-832.
Benedict, JC, KB Pigg and ML DeVore. 2008. Paleowilsonia boglei gen. et sp. nov. (Hamamelidaceae) from the Late Paleocene Almont flora of central North Dakota, USA. International Journal of Plant Sciences 169: 687-700.
DeVore ML and KB Pigg. 2007. A brief review of the fossil history of the family Rosaceae with a focus on the Eocene Okanogan Highlands of eastern Washington State, USA, and British Columbia, Canada. Plant Systematics & Evolution 266: 45-57.
Ickert-Bond SM, KB Pigg, and J Wen. 2007. Comparative infructescence morphology in Altingia Noronha and discordance between morphological and molecular rates of evolution. American Journal of Botany 94: 1094-1115.
Nishida H, KB Pigg, K Kudo, and JF Rigby. 2007. New evidence of reproductive organs of Glossopteris based on permineralized fossils from Queensland, Australia. I. Ovulate organ Homevaleia gen. nov. Journal of Plant Research 120: 539-549.
Pigg, KB, RM Dillhoff, ML DeVore, and WC Wehr. 2007. New diversity among the Trochodendraceae from the Early/Middle Eocene Okanogan Highlands of British Columbia, Canada and northeastern Washington State, USA International Journal of Plant Sciences 168: 521-532.
DeVore ML, P Kenrick, KB Pigg, and RA Ketcham. 2006. Utility of high-resolution X-ray computed tomography (HRXCT) for paleobotanical studies: an example using London Clay fruits and seeds. American Journal of Botany 93: 1848-1851.
Pigg KB, ML DeVore and WC Wehr. 2006. Filicalean ferns from the Tertiary of western North America: Osmunda L. (Osmundaceae: Pteridophyta), Woodwardia Sm. (Blechnaceae: Pteridophyta), and onocleoid ferns (Filicales: Pteridophyta). Fern Gazette 17: 279-286.
Pigg KB, and H Nishida. 2006. The significance of silicified plant remains to the understanding of Glossopteris-bearing plants. Journal of the Torrey Botanical Society 143: 46-61.
Taylor W, ML DeVore, and KB Pigg. 2006. Susiea newsalemae, gen. et sp. nov., (Nymphaeaceae): Euryale-like seeds from the Late Paleocene Almont flora, North Dakota, USA. International Journal of Plant Sciences 167: 1271-1278.