Gradual warming prior to the end?Permian mass extinction

The biggest known mass extinction in the history of animal life occurred at Permian–Triassic boundary and has often been linked to global warming. Previous studies have suggested that a geologically rapid (<40 kyr) temperature increase more than 10°C simultaneously with main pulse. This hypothesis is challenged by geochemical palaeontological data indicating profound environmental perturbations rise prior extinction. Using secondary ion spectrometry (SIMS), we measured oxygen isotope ratios from Changhsingian (late Permian) ostracods north-western Iran. Our show ambient seawater began least 300 kyr event. Gradual warming approximately 12°C was probably responsible for initial degradation eventually culminated end-Permian