Email Print Share
April 30, 2010

Reduced Oxygen Contributed to "Great Dying" (Image 2)

The red line shows atmospheric oxygen amounts over time. The black line indicates the altitude in today's atmosphere where that amount of oxygen is found. When oxygen levels were at their lowest, around 240 million years ago, an animal living at sea level would have experienced oxygen availability similar to that today at 17,400 feet.

As atmospheric oxygen decreased in the late Permian period, hypoxia, or insufficient oxygen in bodily tissue, would have become an undeniable problem for Earth's terrestrial species. National Science Foundation-supported researchers predicted that eventually, because oxygen levels decrease as altitude increases, only land near sea level would have been habitable on the relatively new supercontinent of Pangaea. As a result of this so-called "altitudinal compression," even modestly high mountains would have represented insurmountable barriers that prevented intermingling and reproduction between nearby populations.

This image accompanied NSF press release, "Reduced Oxygen Contributed To 'Great Dying.'" [See related image Here.]

Credit: Nicolle Rager Fuller, National Science Foundation, based on data from Robert Berner, Yale University, and from Raymond Huey and Peter Ward, University of Washington

Images and other media in the National Science Foundation Multimedia Gallery are available for use in print and electronic material by NSF employees, members of the media, university staff, teachers and the general public. All media in the gallery are intended for personal, educational and nonprofit/non-commercial use only.

Images credited to the National Science Foundation, a federal agency, are in the public domain. The images were created by employees of the United States Government as part of their official duties or prepared by contractors as "works for hire" for NSF. You may freely use NSF-credited images and, at your discretion, credit NSF with a "Courtesy: National Science Foundation" notation.

Additional information about general usage can be found in Conditions.

Also Available:
Download the high-resolution JPG version of the image. (187 KB)

Use your mouse to right-click (Mac users may need to Ctrl-click) the link above and choose the option that will save the file or target to your computer.