Couldn't follow the link, but this is no new theory. The idea that this extintcion was caused by a drop in O2 levels has been around since I was a child (just prior to the event itself!). However, nearly all the other thoeries for the cause of this event would include a loss of oxygen. Global firestorms would accompany meteorite impacts or massive volcanic activity. And any global disruption of animal life will result in a drop in oxygen, making cause and effect difficult to determine.
Ivan, how do you find the time to read all these things from everywhere AND make all these posts? It's fantabulous!
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