Re: Cretaceous taeniodont

["David Marjanovic" <david.marjanovic@gmx.at>]

> But this is a serious question.  Much is made about the explosive
> diversification of mammals _after_ the K/T.  And there is good reason for
> this!  But increasing evidence of diversity--especially with regard to
> niche utilization and size--before the K/T is also an important
> phenomenon.

The increased diversity is totally ridiculous compared to anything Cenozoic.
In addition, all big Mesozoic mammals that have been mentioned in this
thread were carnivores sort of like a weasel or badger -- that's not a lot
of niches. (The one that hasn't been mentioned, *Kollikodon*, is a problem
of its own...)

> > And then there's always *Repenomamus*, bigger than any of the three and
> > roughly 50 million years older, and coexisting with *Gobiconodon* which
> > reached the above dimensions.
>
> OK.  Another important phenomenon.  Why then and not later?

Why then and not earlier?
Not that we knew it didn't happen earlier. Middle Jurassic mammals are
similarly rare as Middle Jurassic dinosaurs. Late Jurassic multituberculates
flood all vertebrate microfaunas, but they seemingly appear out of nowhere.