Bacterial colonization of land 2.75 BYA may have set stage for Great Oxidation

A drill core from the 2.5 billion-year-old Mount McRae Shale formation in Western Australia, which originally was fine-grained ocean sediment, shows high concentrations of sulfide and molybdenum. That supports the idea that most of the sulfate came from land, likely freed by microbial activity on rocks. Some data for the research came from the Mount McRae formation. (Image: Roger Buick/UW)

New research from ESS scientists suggests that breakdown of continental rocks by large bacterial populations may have enhanced ocean life. This in turn may have set the stage for the Great Oxidation Event, 2.4 billion years ago. Doctoral student Eva Stüeken is the first author on this newly published research, along with professors David Catling and Roger Buick. Read more from UW News about this exciting research, and/or check out the advance online publication (subscription to Nature Geosciences required)!

Dinosaur die-out might have been second of two closely-timed extinction events – UW News

Thomas Tobin clears sand from around the fossil of a giant ammonite he found in 2009 on James Ross Island in Antarctica. (UW News)

The most-studied mass extinction in Earth history happened 65 million years ago and is widely thought to have wiped out the dinosaurs. New research indicates that a separate extinction came shortly before that, triggered by volcanic eruptions that warmed the planet and killed life on the ocean floor. This research was undertaken by ESSThomas Tobin, Peter Ward, Eric Steig and others. Read more about this exciting new finding!