07-03-2009, 07:30 PM
Quote:And the period of greatest overall growth was when the oxygen concentration was highest.The increase in insect and animal size was indeed a result of the higher oxygen concentrations that occurred towards the end of the period (as a result of increased plant life and subsequent binding of carbon, not as a cause). Anyone with a greenhouse knows that plants grow from CO2, though. Besides, when the amount of oxygen in that time was highest, at less then 2 times our current level, the amount of CO2 was 3 times our (pre-industrial) level, so it's not very obvious to think that oxygen was to blame.
Btw, that period was not warmer. It was a glacial period with the same average temperature as today: 14 degrees Celcius. Ofcourse, this can be seen as 'proof' that elevated CO2 levels do not cause global warming. You can also wonder why a large part of earth was a green hell, when it was supposed to be cold.