EARTH Magazine: Downgrading the Great Dying
From EARTH Magazine, January 25, 2017 -- It makes for a dramatic narrative: Roughly 252 million years ago, a mass extinction event killed up to 96 percent of marine life, earning an infamous name in the geologic record, "the Great Dying." However, a new study suggests that this cataclysmic event has been overestimated. In the February issue of EARTH Magazine, read how a University of Hawaii paleontologist is improving our understanding of mass extinction events by exploring the effects of natural variability on background extinction levels, revealing a clearer signal in the noise.
To pinpoint the cause of a mass extinction event, other phenomena must be factored out. In the case of the Great Dying, this means figuring out how many extinctions can be attributed to the intense period of volcanic activity and how many are the result of natural selection and competition. Using statistics, Steven Stanley was able to revise the 96 percent extinction figure to 81 percent - still a serious extinction event, to be sure. To learn more about his methodology and the implications of the new study, read the full article in EARTH: https://www.earthmagazine.org/article/downgrading-great-dying.
The February issue of EARTH Magazine is now available online. Read about new research that suggests that grass and cropland fires produce more nitrogen pollution than wood-burning fires. Or learn how a multiagency study led by the U.S. Geological Survey is mapping the threats posed by solar storms to the domestic power grid.