Cataclysmic Destruction

I was talking to my friend Jack the other day and he mentioned that there was evidence that the oxygen content of the atmosphere had varied between 12 and 30 percent. It is now about 20 percent. So no wonder dinosaurs could fly if the air was 30% oxygen. Jack pointed out that you get much above 30% and you could have spontaneous combustion. So maybe that is what happened to the dinosaurs. The oxygen level got so high that they all just caught fire and burned to death.