Great adaptations and mass extinctions: evolutionary insights from the physiology of extinct plants

WILSON Jon, Assistant Professor à Haverford College (Pennsylvanie)

The terrestrial plant fossil record contains rich morphological diversity that preserves the evolutionary history of plant physiology. Key physiological parameters for individual fossil plants can be quantified by applying mathematical models of fluid flow and cavitation resistance to fossilized xylem. Plant fossils record a variety of extinct ecophysiological strategies, including extreme adaptations for maximum water transport rate or maximum hydraulic safety. This talk will focus on the physiology of Paleozoic Era plants, examining three case studies: the ecophysiology of the earliest vascular plants; convergent evolution of high hydraulic conductivity among plants in Carboniferous Period coal swamps; and the conspicuous extinction of the woody, broad-leaved, Southern Hemisphere circumpolar seed plant Glossopteris during the Permian-Triassic mass extinction.