That makes a lot of sense. I'm embarrassed to say I didn't think about post catastrophe speciation producing the illusion of extinction.
I love it when you talk like that.
I am so an art major, and not a sciency person, so please let me know if I'm talking rubbish, but ...
I wonder if the differing rates of extinction during catastrophic times and normal times has much to do with different mechanisms having a greater or lesser impact.
In catastrophic times, does random chance plays a bigger rôle than normal? What if, as it were, it's a dice roll whether each individual survives the mess, so the more individuals the better chance of a few rolling well and the species surviving.
And what if in more normal times random chance has less effect, so that slow climate change, say, or a shift in migratory patterns of food supplies, or some other big, slow change can have an overall effect, leaving a species high and dry almost at once.
Maybe the less abundant species that go extinct less often in normal times have more mechanisms to survive and find each other than more abundant, easy-to-find species.
Maxx's comments about speciation are also interesting, that an abundant species is likely to generate more competing descendant species, and thus possibly compete itself out of existence. Not something I had thought of, and definitely a good point.
By the way, just because I love cephalopods, I followed from that article to
this one, which says that after the End-Permian Extinction of 252.6 million years ago, ammonoids (shell-squids) recovered their pre-extinction diversity 10-30 times faster than previously estimated, reaching the same diversity within only one million years.
It also says that cephalopods (octopuses and squids) barely squeaked through, with maybe only two or three species surviving, and only one that became ancestor to all modern cephalopods.
A slight sidetrack there, but I think it's neat.
