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Well we also have this from the NIH concerning global oxygen levels and natural fires: "Fire ignition requires a source of fuel, heat, and oxygen, whereas its propagation also depends on climate (weather) and topography (5). Experimental data (6–10) provide the following observations about O2 levels and fire in the fossil record: At levels <13%, except under exceptional circumstances, wildfires will not ignite and spread irrespective of moisture content (7). Between 13% and 16% fires would be rare and would only burn very dry plant material. Ecologically, only vegetation growing in environments liable to drying would burn. Between 18% and 23% fire occurrences would be similar to those under the PAL of 21%, where plant matter (fuel) must have low moisture content; dry seasons help to effect this decline in fuel moisture and permit the rapid spread of the flame front and fire propagation (11). At >25% fires would become widespread, especially in wetter climatic areas, because of the prevalence of lightning strikes. At levels >30% fire activity would be globally distributed. However, at levels >35% plants have been predicted to burn irrespective of drying, resulting in an upper limit of O2 beyond which fires could not be extinguished (8–10). These limits define the fire window (12), within which O2 levels are constrained where charcoal, a pyrolysis product of fire, is found in the fossil record." Global fires would cause extinction as well.

Sorry for the formatting problem.

It’s too much to bear; one study by the U.S. gov did in 2005 allowed that rising O2 levels led to the rapid growth of the dinosaurs but didn’t go farther than an abstract on that point alone.

By way of ending this fruitless journey for the time being, I leave you this from the Answerbag:

“by Glenn Blaylock64 on Mar 31, 2005 at 2:32 pm Permalink

This answer was last edited on: Apr 1, 2005
It is thought, that the herbivorous dinosaurs grew big as a defensive mechanism. (Today, there are not many (if any) predators that will take on an adult elephant.) In response to this many of the predators grew bigger so that they could take on the large herbivores. So, we had a positive feedback loop that developed. The larger dinosaurs were able to out compete the smaller ones in their quest for survival. So, the genes that would produce yet larger animals were propagated producing larger and larger dinosaurs. That is the theory any way.

BTW, we also saw this happen with mammals after the dinosaurs died out. However, many of the larger mammals died out at the end of the last ice age. Just why is a matter of dispute. Some say it was over hunting by a new species that appeared at about that time (homo sapien sapien, aka Cro-Magnon, aka modern humans). Others say that they died out because they could [not] cope with the rapid climate change that occurred when the ice age ended.”

Wait for me, Alice. Damn it, rabbit!, slow down...