The same ocean conditions behind Earth's worst mass extinction are forming again today, Stanford-led study finds
A new Stanford-led study in PNAS offers the clearest picture yet of why the Great Dying, Earth's biggest mass extinction 252 million years ago, hit some ocean groups far harder than others. Warming, oxygen-poor seas killed animals least able to tolerate heat and low oxygen. Resea
About 252 million years ago the Permian-Triassic extinction, the Great Dying, wiped out 96 percent of marine species and around 70 percent of land animals. A new Stanford-led study in the Proceedings of the National Academy of Sciences is the first to combine biological data from both the groups that were devastated and those that survived. Nearly all brachiopods, shelled animals resembling clams, disappeared, and seafloor-anchored sea lilies were almost erased, while only about half of the mollusks died out. The pattern tracks metabolic tolerance: animals less able to handle rising heat and falling oxygen died at far higher rates. The researchers note that today's oceans are warming and losing oxygen through fossil fuel emissions, the same chemistry that preceded the collapse. Sources: Stanford Doerr School of Sustainability, phys.org, ScienceDaily, EurekAlert (PNAS study).