Last updated on April 18, 2014 at 7:29 EDT
Reduced Oxygen Contributed To Great Dying Image 1
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Reduced Oxygen Contributed To "Great Dying" (Image 1)

July 26, 2010
A depiction of the supercontinent Pangaea some 250 million years ago shows regions where oxygen was insufficient for animal survival. Because oxygen levels decrease with increasing altitude, the more mountainous "hatched" areas would have prevented intermingling and reproduction between nearby animal populations.

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 a result of this so-called "altitudinal compression," even modestly high mountai. As ns 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.]