RE: Eodromaeus, new basal theropod from Triassic in Argentina

[Jaime Headden <qi_leong@hotmail.com>]

Jura/Jason wrote:

<I'm assuming you are referring to _Scansoriopteryx/Epidendrosaurus_ and 
_Juravenator_. Both are specimens in which the alleged feather/scale 
association is present, but both are also highly ambiguous examples. For 
_Scansoriopteryx/Epidendrosaurus_ the authors mentioned that the scale 
impression by the tail was not found in "articulation" with the tail and had 
likely migrated from the tarsometatarsal region.>

  I'm only going to comment specifically on this. The authors of the paper in 
question (Czerckas & Yuan, 2002) can neither confirm nor deny the original 
position of the impression (unlike the filaments which are carbonized traces 
left in the bedding plane and slightly atop it, the impressions are embedded 
into the plane and are preserved in a higher grade of relief than the filaments 
around the arms and back/neck. While much of the skeleton is dissarranged, the 
entire body portion, hips, and tail are articulated, and it is unlikely that 
the impression derives from elsewhere on the body. It is also irrelevant. My 
understanding is that the authors chose this to bolster the restoration of a 
fully filamented tail, which would not be contradicted by squamous impressions 
in the tail as scale-tailed squirrels (*Anomalurus*) preserve a possible 
analogue, where the tail is scaled ventrally but furred dorsally and laterally.

  Czerkas, S. J. & Yuan C. 2002. An arboreal maniraptoran from northeast China. 
pg. 63-95 in Czerkas (ed.) _Feathered Dinosaurs and the Origin of Flight_. _The 
Dinosaur Museum Journal 1_.

Cheers,

Jaime A. Headden
The Bite Stuff (site v2)
http://qilong.wordpress.com/

"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 
Backs)