I’m not married to any idea of what happened, but the guy in the video seemed confident and had a good argument that zero fossils were found in the impact debris layer. How do we reconcile that?
I do like my theory that cooling produced an unfavorable environment as well.
It looks like they were gradually selected against as big creatures take advantage of abundant resources. Insects were also big back then, but not now. And it’s hard for me to believe that a single event would eradicate all the one species while leaving the others. If nothing else, the damaged species should re-evolve instead of going extinct forever if it weren’t the climate that dictated who had the advantages.
I’ve also not been able to process how the sun remains a constant stable temperature for so long instead of a steady cooling over time. Any fire I’ve ever seen gets hotter and then cooler until it extinguishes.
And I’ve no idea what drifting around in the spiral arms does to the climate, but it can’t be insignificant.