Plants couldn’t cut the Permian extinction
The Earth is very active beneath our feet; ask anyone who’s been through an earthquake (I’ve been through the big San Fernando quake). Outside of major quake zones the Earth’s surface looks almost eternal. However, in the longer term of millions of years there have been – and will be - massive and geographically extensive upheavals.
Julian Rogger at ETH, Zurich, and five colleagues analyzed three huge and long-lasting reshapings of the land. One massive volcanic outpouring 252 million years ago created the Siberian Traps. The basaltic lava covered an area about the size of the continental United States, to an average depth of about 600 meters (2,000 ft). Wow!
The researchers paid attention to the lava, of course, and to the emission of greenhouse gases but especially on how vegetation got knocked back for millions of years. Plants could not act to bury CO2 fast enough; the greenhouse heating stayed. Plants can adapt genetically to rinsing temperatures, but apparently not fast enough this time – much plant life apparently died or lost function. So, earth experienced the greatest mass extinction, killing off 81% of species in the ocean and about ¾ of all vertebrate animal species on land….by killing off perhaps 99% of all individual organisms. Lava + plants = a story.
This has been an outreach activity of the Las Cruces Academy, viewable at GreatSchools.org
Ref.: Science, 9 Aug. 24, pp. 661 ff.
