Paleophysiology and end-Permian mass extinction

Physiological research aimed at understanding current global change provides a basis for evaluating selective survivoyship associated with Permo-Triassic mass extinction. Comparative physiology links paleontological and palcoenvironmental observations, supporting the hypothesis that an end-Permian trigger, most likely Siberian Trap volcanism, touched off a set of physically-l inked perturbations that acted synergistically to disrupt the metabolisms of latest Permian organisms. Global wan-ning, anoxia, and toxic sulfide probably all contributed to end-Permian mass mortality, but hypercapnia (physiological effects of elevated P-CO2) best accounts for the selective survival of marine invertebrates. Paleophysiological perspectives further suggest that persistent or recurring hypercapnia/global warmth also played a principal role in delayed Triassic recovery. More generally, physiology provides an important way of paleobiological knowing in the age of Earth system science. (C) 2007 Elsevier B.V. All rights reserved.