the inevitable conclusion is that the first wave of Sapiens colonisation was one of the biggest and swiftest ecological disasters to befall the animal kingdom.
The Permian–Triassic extinction event is the worst disaster in the history of the animal kingdom. That isn’t in question.
The current Holocene mass extinction (which the earth is currently undergoing, largely caused by human activities) is on par with the Cretaceous–Paleogene (K-T) extinction event, but it is not proposed that this event is at the same level of intensity as the P-T event.
If the author is speaking of shorter-term disasters, the asteroid impact that formed the Chicxulub crater and caused the K-T extinction is, I would say, a greater disaster in terms of how far the impacts reached and how quickly it caused ecological upheaval against an event that occurred literally in one moment in time.
