Metal-induced stress in survivor plants following the end-Permian collapse of land ecosystems

Abstract Teratological spores and pollen are widespread in sediments that record the Permian-Triassic mass extinction. The malformations thought to be result of extreme environmental conditions at time, but mutagenic agents precise timing events remain unclear. We examined abundance teratological sporomorphs metal concentrations a tropical peatland succession southwestern China. find significant peak spore tetrads lycopsid plants (as much as 19% all sporomorphs) coeval with increases Cu Hg above main terrestrial extinction interval, which marks loss Permian Gigantopteris forests, increased wildfire activity, disappearance coal beds. Thus, peatlands, mutagenesis affected only surviving plants. Mutagenesis was likely caused by toxicity, linked loading, not itself direct cause crisis.