Date: Wed=2C 21 Oct 2009 00:20:50 -0700
From: ddkrentz@charter.net
To: mike@indexdata.com
CC: sherekhanjunior@hotmail.com=3B dinosaur@usc.edu
Subject: Re: Dinosaur "spikes"
It has become extremely fashionable now to depict EVERY dinosaur with
dermal spines these days. There are a couple instances of them=2C
as in
some hadrosaurs=2C but if we are going by what most fossil
integument is
proven to exist than feathers would be a winner by a long shot. As
cool as dinos look with spiky mohawks and poky little bits jutting
out
of every dorso-ventral midline surface possible one must be wary of
what is in fashion and what is known. In my own work this has been a
struggle because dinosaurs almost seem 'naked' without them!
I think some would even dispute the psittacosaur quills (?) which
is the basis for many later ceratopsians having spines and quills.
The new Triceratops skin impressions do show signs of "something"
growing out of the large osteoderms on its back...so at least thats
exciting.
Funny this would come up right now=2C I was preparing a post
regarding the reasons for midline integuments/ornamentation on
animals
in general. Clear silhouettes? easy recognition? Protection?
D
On Oct 21=2C 2009=2C at 12:06 AM=2C Mike Taylor wrote:
2009/10/21 Ezra Toranosuke :
I was wondering which types of dinosaurs are known to have had that
so-classic row of iguana-like spikes on their backs. I know that
Diplodocus had them=2C and it seems that Edmontosaurus and
Ceratosaurus did too.
But are there any others? And what about those reconstructions that
show Triceratops with osteoderms on its back?
No=2C you don't know that Diplodocus had them. Czerkas (1994)
described
fourteen dermal spines found in the Howe Quarry=2C but among these
only
ones associated with skeletal remains were found with uninformative
rod-like distal caudals that could have belonged to any
diplodocoid=2C
or indeed almost any sauropod. So while it is certainly possible
that
Diplodocus had "that so-classioc row of iguana-like spines on their
backs"=2C all we actually KNOW is that SOMETHING had spines on the
distal part of its tail.
=20