Re: Pterosaur diversity (was: Re: Waimanu)

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

> There was certainly a rapid shift toward gigantism in the early history of
> sauropods (Late Triassic/Early Jurassic).

Interestingly, I do get an increase for presacral length over 
Sauropodomorpha as a whole, but the probability that this is a random 
outcome of random data is _88 %_.

> (e.g., _Brachiosaurus_ and _Seismosaurus_ in the Late Jurassic,
> _Argentinosaurus_ and _Sauroposeidon_ in the Early Cretaceous).

Here's hoping for more material of *Puertasaurus* (Maastrichtian, and mighty 
big).

> [...] ceratopsians certainly appear to have gotten bigger

Ceratopsids, yes (probability of the increase I get being all random = 0.511 
%, so the increase is highly significant... if it isn't an artefact of 
coding them all as either "Campanian" or "Maastrichtian", that is). But if I 
just add 5 more species to get Coronosauria complete (*Bagaceratops*, 
*Protoceratops* spp., *Leptoceratops*, *Montanoceratops*), the significance 
shrinks below what is considered acceptable (it rises 26-fold to reach 13 
%). The joys of taxon sampling problems. And then comes the unmeasurable 
*Zuniceratops*, Turonian in age, and creates quite impressive ghost 
lineages... now imagine what's going to happen to all these numbers if 
someone discovers a diverse Coniacian or Santonian ceratopsid fauna...

(That is... forget the numbers anyway, at least their exact values. I coded 
*Zuniceratops* as Cenomanian. Shit.)