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While perusing the net I found http://www.sino-collector.com/eng/_private/cjyd/zjlt/hjs-hs/hjs02-1.htm ,
The Origin of Birds and their Early Evolution, by Hou in 2000. I don't
know if it's published, but I doubt it (it's titled a lecture). The
translation is not great, but it contains several notable topics-
The abstract mentions two genera- Zhonghuaornis and
Perpiaoornis. These are listed with "archaeopteryx" and are said to be
covered with filaments, which supports the dinosaur-bird connection.
Though the -ornis ending would suggest these are birds, the context indicates
they are non-avian (or else their insulation would not be notable). These
are not mentioned again on the website, but there are clues pointing toward
their identity. In section 2.1, Hou again lists three supposed non-avian
dinosaurs with filaments, this time they are "original archaeopteryxs",
Weiyuornis and Yiwaibeipio. Original archaeopteryxs is obviously
Protarchaeopteryx. Weiyuornis is described as a taxon originally reported
as a feathered dinosaur, with symmetrical remiges, retrices and twenty-two
caudal vertebrae. So it is Caudipteryx. My guess for Yiwaibeipio is
Beipiaosaurus, the fourth classic feathered dinosaur discovered. So
we know Hou calls some described taxa by different names, perhaps these are some
varient of their Chinese names, like Kuming-Long was for "Dilophosaurus"
sinensis. The archaeopteryx mentioned in the abstract is therefore
Protarchaeopteryx and the other two genera are Caudipteryx and
Beipiaosaurus. Based purely on how they sound compared to their other
alternate names, I'd say Zhonghuaornis is Caudipteryx and Perpiaoornis is
Beipiaosaurus.
The website is a good resource for photos of Yixian
birds, though several are mislabeled and the species names are
translated-
Confuciusornis sanctus-
page 1, second from top- referred specimen IVPP
V110304
page 2, left of 2.2- holotype forelimb
page 2, right of 2.2- paratype pelvis and
hindlimb
Jibeinia- page 3, bottom right
Sinornis santensis (holotype of Cathayornis
yandica)- page 3, third and fourth from top left
Sinornis? caudatus-
page 3, first and second from top left-
holotype
page 3, third from top right- referred specimen
IVPP V10533
Otogornis- page 3, second from top
right
page 3, second from bottom right- unknown pelvis
(figure 54 in Hou 1997)
Some specific critiques-
Hou continues to state the Lower Yixian Formation
is Late Jurassic, when it is Middle Barremian. Thus, though he says
Confuciusornis, Liaoningornis, Eoenantiornis and Liaoxiornis were the earliest
pygostylians, there are taxa from Spain, England, Mongolia and North Korea which
predate or coexisted with them (http://www.cmnh.org/dinoarch/2002Jan/msg00544.html).
Thus, his conclusion that enantiornithines evolved in East Asia is
unfounded.
Liaoningornis is still claimed to be euornithine,
and thus prove an early separation of sauriurines and euornithines. It is
more probably an enantiornithine (whatever the status of the group), as
explained here- http://www.cmnh.org/dinoarch/2002Jan/msg00962.html .
Liaoxiornis is said to be a very small taxon, with
a small sternum and short forelimbs. It is of course a juvenile (see http://www.cmnh.org/dinoarch/2001Jul/msg00344.html).
I love how he describes ABSRDers-
"mainly
biologists and paleontologists who have a solid foundation of biology , clear
train of thought and comprehensive consideration , considering the essence of
the developing of biology and biogenetics from a viewpoint of biological
evolution, analysing on the basis of fossil records and the achievements of
genetics and embryology , and so can put forward problems hard to be explained
by the one who support dinosaur-origin theory."
LOL I'd like to hear these great problems. I
suppose we BADDers are just as opinionated, but I found it amusing all the
same.
Arguments against BADD-
1. Scales couldn't evolve into feathers (who's
saying they did and why would this work better if birds evolved from
megalancosaurs [which Hou posits as bird ancestors in his 1997
paper]?).
2. The filaments were really parts of a dorsal sail
(hasn't this died yet?).
3. Caudipteryx's remiges are "completely different"
from birds' because they are symmetrical and lack barbules. Thus,
Caudipteryx inherited its pseudofeathers from the common ancestor of dinosaurs
and birds. Then again, he says it could be a post-Archaeopteryx flightless
bird based on the reduced number of caudal vertebrae that supposedly form a
protopygostyle. See the relationships section of http://www.cmnh.org/dinoarch/2001Feb/msg00333.html for
arguments against this.
4. Megalancosaurus has a similar neurocranium and
scapula.
5. The old digital homology argument.
6. The old "only Cretaceous dinosaurs are said to
be birdlike" argument. This one is phrased particularily
amusingly-
"The events of
biological evolution have arrangement in time order. ... The scholars who
hold that birds originated from dinosaurs neglect this important factor in the
process of biological evolution."
I wonder when "account for and logically explain"
became synonymous with "neglect".
Hou claims that he would accept BADD if there was
"the discovery of the small beast-foot dinosaurs
which covered with feather conformation and whose limb had not been
specialized." Protarchaeopteryx should have done
it then, as its limbs are basal maniraptoran in design. I would hope cf.
Sinornithosaurus and the undescribed Yixian eumaniraptoran convinced
him.
Mickey Mortimer
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