Re: Speculative dino species

["aspidel" <aspidel@infonie.be>]

----- Original Message -----
From: Thomas R. Holtz, Jr. <tholtz@geol.umd.edu>
To: <Srnka.Christopher@mayo.edu>; 'Daniel Bensen' <dbensen@gotnet.net>
Cc: <dinosaur@usc.edu>
Sent: Friday, July 27, 2001 10:12 PM
Subject: RE: Speculative dino species


> > From: owner-dinosaur@usc.edu [mailto:owner-dinosaur@usc.edu]On Behalf Of
> > Srnka, Christopher P.
> >
> > A list-wide project would be nice...any other takers?

Yep, the idea is funny, I'll try to make a drawing or two when I get time,
maybe this winter.

>> Perhaps we
> > could play
> > out a few "what if" scenarios on a message board somewhere, so
> > artwork could
> > be displayed....I got on this kick after doing some sketches of what I
> > thought might have been another evolutionary path for dromaeosaurids....
> >
> > http://www.comixmatrix.com/artists/image.asp?id=266385

Got the image, sonds cool. Is this "dromaeosaur" more intelligent than
JP-raptors (joke)?

> A couple things to keep in mind (which Greg Paul did in his
> reconstructions):
>
> I) Consider how much change (or rather, as is often the case, how little
> change) occurred within the various lineages throughout the Cretaceous.
> That is, how much morphological difference is there between the ?Barremian
> _Sinornithosaurus_, the Aptian-Albian _Deinonychus_, and the Campanian
> _Velociraptor_ and _Bambiraptor_ (a space of 45 million years or more).
>
> II) If the conciet is simply "the K/T mass extinction did not occur", no
> cheating by having the survival of taxa we are reasonably certain WERE
> extinct before the end of the Maastrichtian.  For example, no Cenozoic
> centrosaurines or stegosaurians or coelophysoids.

And were there some species (or groups) which got rarer and rarer during the
LK?
Could Pterosaurs have survive with the evolution of birds?

> III) Keep in mind the other secular changes in Earth's environment during
> the Cretaceous: the continued plate tectonic development of the Earth; the
> late Eocene extinctions and the development of the psychrosphere (and the
> resetting of Earth's thermostat, phase 1); the spread of the grasslands in
> South America, and later in Africa, Eurasia, and North America;

IMHO, we don't know anything about evolution of the vegetation without a K/T
mass extinction!
I tell this for those who wanna draw speculative dinosaurs in speculative
landscapes.
Without K/T mass extinction, did grasses appear? And what about evoluted
families like Lamiaceae, Asteraceae, or orchids?
And what about fungi?  Well, well.........................

> the
> Himalayan orogeny and resetting of Earth's thermostat, phase 2; the
> developement of the Isthmus of Panama and the resetting of Earth's
> thermostat, phase 3 (aka the late Cenozoic ice ages).
>
> Thomas R. Holtz, Jr.

Friendly,
                Luc J. "Aspidel" BAILLY.