[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
RE: Eodromaeus, new basal theropod from Triassic in Argentina
The argument for non-squamous integument is not a fanciful one when dealing
with any basal dinosaur. The issue with regards to *Tianyulong* especially
evokes an integument much akin to that of *Sinosauropteryx*, preferring then an
argument of parsimony: It is easier to conceive that integument shifted from
scales to "fuzz" once than it is to assume it did so repeatedly throughout
Dinosauria. Whether parsimony forms the better argument over any other is to be
seen; the next contravening hypothesis, which I assume Jura/Jason may prefer
for the moment, is that all Dinosauria should be seen to be squamous (like
crocs and other archosaurs for which integument is known) unless proven
otherwise, but this is not the null-hypothesis. Instead, based evenly on
Phylogenetic Bracketing and historical assumption, we can i
This inference becomes greater than 50% in favor of "fuzz" when pterosaurs
are placed between birds and crocs on the avian lineage, or even between
Archosauria and the base of Archosauropmorpha. In the latter scenario, with the
presence of feathers at one end, "fuzzy" taxa along that lineage, and "fuzzy"
taxa at the base, it can be argued that without contradicting evidence, "fuzz"
would be the likelier inference, including for stem-crocs. This is based solely
upon Phylogenetic Bracketing. Placing pterosaur4s closer to birds than crocs
should only increase the likelihood for one lineage of -- rather than the whole
of -- Archosauria, but weighs greater preponderance on the argument that "fuzz"
is the null hypothesis of integument.
Jaime A. Headden
The Bite Stuff (site v2)
"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)
"Ever since man first left his cave and met a stranger with a
different language and a new way of looking at things, the human race
has had a dream: to kill him, so we don't have to learn his language or
his new way of looking at things." --- Zapp Brannigan (Beast With a Billion
> Date: Fri, 14 Jan 2011 07:56:57 -0800
> From: email@example.com
> To: firstname.lastname@example.org
> Subject: RE: Eodromaeus, new basal theropod from Triassic in Argentina
> --- On Fri, 1/14/11, Jeff Hecht wrote:
> > At 2:55 PM +0000 1/14/11, David Howlett wrote:
> > >Interesting how the pop culture image of small
> > predatory dinosaurs is slowly beginning to shift - did
> > anyone else notice that the illustration in that article
> > included a fuzzy layer of down? Obviously there is no
> > evidence in the slightest for this, but it does demonstrate
> > that the concept of feathered dinosaurs is becoming
> > ubiquitous - amazing considering that even a decade ago
> > there was still a lot of resistance to the idea in the
> > mind's eye of the public!
> *Ugh* yeah, it's annoying as crap. I don't think the illustration is a sign
> of the public's increasing acceptance of fuzz on dinosaurs. I believe it has
> more to do with the paleoart community, with many (if not most) of the high
> profile paleoartists preferring the fuzzy look over the scaly one.