Quote:
Originally Posted by niky
High atmospheric CO2 doesn't cause the mass extinction of land vertebrates when there are no land vertebrates to go extinct, so it doesn't really tell as anything about the Triassic extinction.
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(I could be wrong) ... but ... I don't think the claim jamesqf made was some kind of suggestion about only vertebrate life in particular being effected ... It was my impression , that the reference to vertebrate life used in the described (unprecedented) level extinction event ... was instead used as a magnitude / scale indicator of the massiveness of the extinction event that jamesqf predicts in less than 1,000 years.
As such .. it is not a question of if there was specifically vertebrate life at a point being looked at ... or if it ever evolved ... but instead ... if there is a extinction level event of the kind of magnitude jamesqf predicts... and has listed CO2 as the primary cause of that magnitude of extinction event.
Jamesqf then referenced the Triassic extinction event as an example to support his predicted extinction event .. and suggested that it was the ~2,000 ppm CO2 of the Triassic that was the primary cause of that extinction event ... thus correlating it back to his CO2 based predicted extinction event.
If ... instead of the Cambrian ... you prefer ... my same point can also be made by looking at the historic record of CO2 ppm ... and looking for duplicate Triassic extinction events when there were other periods with 2,000 ppm or higher ... to see if jamesqf's expectation is supported by the record of what has actually happened ... and ... it turns out ... the record disagrees ... we don't see that kind of correlation with CO2 ppm and that kind of magnitude of extinction level events happening every time we see ~2,000 ppm.
File:Phanerozoic Carbon Dioxide.png - Wikipedia, the free encyclopedia
Quote:
Originally Posted by niky
More cheerfully, it was a world with an average temperature of 45-46 degrees C and with 15% more ocean coverage than today. Lovely place to live.
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It's description seems very unpleasant... for those and other reasons... Glad I don't live during that time.