Re: Longisquama shed plumes

[Tim Williams <twilliams_alpha@hotmail.com>]

Greg Paul wrote:

> I give corrected mass estimates for giant ground birds in Dinosaurs of the
> Air which show that the biggest New Zealand, Austalian and Madagascar 
> weighed
> about the same, something like 380 kg.

Yes, this is in Appendix 2 of DA, and the value of 380 kg is based on 
volumetric studies.  But I wonder if the huge skull and robust skeleton of 
_Dromornis_ made this a heavier bird than small-headed ratites like 
_Aepyornis_ and _Dinornis_, which were of comparable height but of more 
gracile build.  Dromornithids, which appear to be of anseriform (or at least 
galloanserine) stock, were built rather differently to cursorial ratites.  
Just look at Fig. 8.4 in DA.

> Isolated Early Cretaceous feathers are known from several continents. One
> from Spain has even received the (rather useless) name *Ilerdopteryx
> viai*.

Yes, there is also _Cretaaviculus sarysuensis_, this time from Kazakhstan.  
These feather-based taxa are not very helpful.  Still, at least 
_Ilerdopteryx viai_ appears to represent a genuine featherm and (presumably) 
came from a theropod.  One fossil specimen from Spain, originally regarded 
as a bird and named _Priscavolucris montsechi_, was subsequently shown to be 
a fossil hybodont shark.  I think it was renamed _Lissodus montsechi_.

Jaime Headden wrote:

> This might even be expected if there were a layer of
> mud beneath the animal overlying the plumes, if the fossils were not 
> already
> attached, such as might happen if the animal were to have died and been 
> buried
> nearly on top of these structures, never having borne them. The neck 
> squamation
> and the brachial "parafeathers" may very well be natural and part of the
> animal, but the plumes may not be.

It would be hilarious if the 'parafeathers' of _Longisquama_ turned out to 
be a bunch of leaves that just happened to be positioned under the partial 
skeleton.

Cheers

Tim