Our hypothesis of terminal-Permian vertebrate mass extinction by pulmonary edema (Retallack et al., 2003) rested on observations of victims (1) and survivors (2) of mass murder, and a plausible lethal weapon (3), as follows: (1) mass mortality of vertebrates at the Permian-Triassic boundary; (2) improved respiratory capacity of earliest-Triassic survivors (development of secondary bony palate, shortened internal nares, high dorsal vertebral spines, thickened ribs, barrel chests, shortened limbs, reduced lumbar ribs); and (3) evidence of dramatically lowered earliest Triassic atmospheric oxygen levels (berthierine in paleosols, lowered stomatal index of seed ferns from increased carbon dioxide, declining carbon isotope...

First Page Preview

First page PDF preview
You do not currently have access to this article.