Re: Zhonghuaornis, Perpiaoornis, Weiyuornis and other things on Hou's site

["Jaime A. Headden" <qilongia@yahoo.com>]

  First, Perpiao is just a spelling variant of Beipiao, but note that many
taxa come from around Beipiao City, where this name is popular. The
pronounciation of "Beipiao" falls between the hard "b" and the "p" sounds,
and the "r" is very soft, but as far as I know, is present. One notes the
same thing in "Boluochia", which is pronounced with a terminal "r" sound.

  Blah blah ... let me leave the rest of the Chinese to people who know
more than me... lol

Mickey Mortimer (Mickey_Mortimer111@msn.com) wrote:

<Hou continues to state the Lower Yixian Formation is Late Jurassic, when
it is Middle Barremian.>

  The verdict is hardly out on this one, though recent data does in fact
support a Barremian age for this level. The problem is two-fold: sampling
requires every locality be tested the same way (Smith et al have discussed
this extensively), but where many localities with important finds are not.
Some levels, such as the Jiufotang, may straddle the J/K boundary, and the
Yixian, which overlies the Jiufotang, may or may not lie at the base of
the K, or straddle it itself, or be Jurassic instead. Second: because of
the different sampling methods and in general the difficulty in locating
volcanoclastics, concise dating may not be possible. The arguments for a
Jurassic level remain solely on phylogeographical import, including the
earlier papers, most of the taxonomic papers, and especially detailed in
Luo's Refugium hypothesis. The only thing going for the Cretaceous age is
the volcanoclastics, and two different isotope analyses produce different
ages, including J/K straddle up to middle Barremian. So it's not like the
dating is very concrete.

<2. The filaments were really parts of a dorsal sail (hasn't this died
yet?).>

  I was amazed when I heard this theory pop up, then heard how Martin
challenged them to find these on frogs, and he'd beleive. Problem is,
evidence for filamentous integumental covering has been found almost a
hundred years before now in messel in mammals, but absent in reptiles in
the level. That this did not come up has shocked me utterly, and should
have been the very first argument against the dorsal frill hypothesis.
That Ji, Ji, and Padian, in disucssing what is some of Currie's ongoing
research (in Mesozoic Vert. Life), showed fully that the filaments occured
more over than the dorsal margin of the spine (based on intracoastal
filamental preservation, behind the arm, on the side and not the top of
the head, etc.), it seems bizarre that recent papers on the matter still
use the dorsal frill hypothesis and a point of argument. Specifically, to
name one, Ruben and Jones' paper in the feather-origin volume of _American
Zoologist_.

<4. Megalancosaurus has a similar neurocranium and scapula.>

  Bah. So does a chameleon. Renesto described this similarity extensively
in 1997 and pretty much disproved it's affinity to birds. But ... they can
fantasize all they wish....

<5. The old digital homology argument.>

  Without knowing the embryology of various dinosaurs, the argument cannot
be applied to them, no matter what Feduccia wants to see. The evidence is
apparently a non-Maniraptoriform reduction in outer digits, but we do not
know the embryological development of fingers in *Deinonychus*, for
instance.... So the point is interesting, as Maderson showed, but I see no
reason why it argues for or against any hypothesis when half the
participants cannot be comapared.

  Cheers,

=====
Jaime A. Headden

  Little steps are often the hardest to take.  We are too used to making leaps 
in the face of adversity, that a simple skip is so hard to do.  We should all 
learn to walk soft, walk small, see the world around us rather than zoom by it.

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