Yes, I agree about the compulsion to link CO2 and climate warming in general. The subject is still in its infancy, and most scientists have egos (publish or perish, don’t you know!) which translates into a rush to garner headlines.
As you may have guessed, I have a geeky desire to read about paleontology and geologic past events. One of the books I have is by Peter D. Ward, Out Of Thin Air (2006), which discusses the Permian oxygen crash which could have caused the massive, catastrophic extinction associated with that period.
His book is NOT an exciting read, in fact it is quite dry. But he does a very good job of explaining why dinosaurs evolved with the ability to husband oxygen in their bodies, with birds being the connection between the present and the past. He also explains why and how the oxygen crash may have happened 251Million years ago. Chapter 7 is the most interesting part of the book. Ward also details the rise and fall of CO2 as it corresponds with oxygen pecentages in the atmosphere.
Penguins and polar bears are next!