Mutant Fern Spores Point to Mass Extinction Culprit

Photo courtesy U.S. Geological Survey


About 200 million years ago, much of the life on Earth was wiped out in the end-Triassic mass extinction. The catastrophe may have been caused by climate change related to massive volcanic eruptions. Now a team led by Sofie Lindström at the Geological Survey of Greenland and Denmark (GEUS) and including Charles ‘Chip’ Lesher, professor emeritus of earth and planetary sciences at UC Davis, has shown that mercury from these eruptions could have contributed to the disaster. As this video from GEUS explains, the researchers found a pulse of mercury in sediments across the Triassic/Jurassic boundary. Fossilized fern pollen from these sediments shows serious mutations and deformations that could have been caused by mercury poisoning.

— Andy Fell, UC Davis Egghead blog