Re: John Bois on Armadillos at the K/T!

["James R. Cunningham" <jrccea@bellsouth.net>]

Hi, Fabio.  What you say is quite correct, but I'd like to point out that the
earlier Ornithocheirid and Pteranodontid giants seem to have been gone
sometime before the late Cretaceous, later being supplanted by Azhdarchid
giantism.  I wonder if there  may have been some common connection related to
the demise of one and the eventual arising of the other.  Perhaps a decline
in oxygen levels between the two episodes of giantism?  Or a period of
reduced convective activity?  Or?   I don't have a clue what the reason(s)
may have been.  Any thoughts, anybody?

Best wishes,

Jim

Fabio Marco Dalla Vecchia wrote:

> Jaime A. Headden wrote: <<The biggist pterosaurs were in the latest
> Cretaceous, but no causal effect has been determinable, so making
> assumptions on this matter are horribly premature.<<
>
> Actually the so called "giant" pterosaurs were already present during the
> Early Cretaceous. Fragmentary remains have been found in Brazil and
> England. Giantism is not a feature of latest pterosaurs only (see Unwin's
> presentation at Bozeman SVP meeting).
> All the best
> Fabio M. Dalla Vecchia
> ----------------------
> Fabio M. Dalla Vecchia, PhD
> Museo Paleontologico Cittadino
> Via Valentinis 134
> I-34074 Monfalcone
> ITALY
> http://www.fante.speleo.it