Hi Ernest!
Love these kinds of threads. I have some info that will only lend clarity or consternation to the debate, depending on what one believes, but here goes.
250 Million years ago there was an oxygen crash that corresponded to the Permian mass extinction - including marine life, plant life, and animal life - an event which “swept both the land and sea alike”. How could carbon dioxide rise, and especially oxygen levels crash from the early Permian level of 35% to “perhaps as low” as 12% in the early Triassic? How could that have happened?
It’s a good read, Out Of Thin Air by Peter D. Ward, professor of biology, earth and space studies, and adjunct professor of astronomy at the University of Washington in Seattle.
A large part of this book is dedicated to describing the respiratory system of dinosaurs. He believes dinosaurs had a respiratory system more akin to birds than mammals or reptiles, and that dinosaurs thrived in low oxygen environments. That is how they came to be the dominate life form on earth for hundreds of millions of years.
Professor Ward speculates that the formation of Pangaea caused the dramatic oxygen drop “...accompanied by a shorter-term rise in atmospheric carbon dioxide,..”.
This book is a very interesting, detailing an ancient world of extremely hot conditions with very low oxygen levels.
Very interesting...thanks.