Something to ponder about what really happened to trigger plant changes in earlier ages of earth
It’s not just down under
Do a search on methane plumes arctic and read more about the theories
I don't know about methane but they say the CO2 levels were many times higher than they are now when flowering plants first evolved. It doesn't seem logical to me that such a specialized development would first occur when conditions were minimal. Most modern animals, including us, wouldn't exist if it weren't for flowering plants.
Would conditions for us be better if CO2 went back to Triassic era levels? I don't know but we'd better hope nothing causes CO2 to fall below the level that flowering plants can survive.