[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
NEW UPCHURCH PHYLOGENY & MORE
Hi All -
Darren Naish (still computer inaccessible!) asked me to forward
this to the list on his behalf:
-------------------- Begin Original Message -------------------
UPCHURCH, P. 1998. The phylogenetic position of sauropod dinosaurs.
_Zool. J. Linn. Soc._ 124: 43-103
....is out. Paul takes issue with Sereno and Wilson's cladogram and
presents a lot of statistical support for his cladogram.
Monophyly of the Euhelopodidae (including _Shunosaurus_) is
reinstated, and cetiosaurids are paraphyletic. Paul identifies two
major radiations within Neosauropoda: 'Brachiosauria'
(_Camarasaurus_, brachiosaurids and titanosauroids) and
Diplodocoidea. Read the paper, it's fab.
And in the same issue.. (!!!)..
RIEPPEL, O. 1998. _Corosaurus alcovensis_ Case and the phylogenetic
interrelationships of Triassic stem-group Sauropterygia. _Zool. J.
Linn. Soc._ 124: 1-41.
I guess Glenn Storrs' monograph wasn't good enough:) Rieppel finds
that eusauropterygians are paraphyletic, and that _Corosaurus_ is
sister to _Cymatosaurus_, _Pistosaurus_ and therefore to the
Woodbury's work on spinal cord morphology in birds has rightly been
getting a lot of interest recently, and his new paper in _Proc. R.
Soc._ (Woodbury 1998) brings it all together in a very nice review.
Basically, birds have two spinal cord morphologies - the primitive
leiocerate morphology (where cutaneous nerves in the dorsal horn form
only a single map of the body surface), and the unique schizocerate
morphology (where there are two maps side by side). Leiocerate is
primitive (it's, I think, the ordinary tetrapod condition), and is
seen in palaeognaths as well as some gruiforms, pigeons, cuckoos,
piciforms (other than puffbirds and jacamars) and passerines! (The
hoatzin is not a cuckoo). Woodbury argues that these groups therefore
evolved before schizocerate birds, and therefore passerines and other
leiocerates are relatively primitive in the Aves (sensu Gauthier)
tree: as Woodbury notes, this is an accord with some molecular data
(e.g. Mindell et al. (1997)) where passerines also come out as
Another interesting thing resulting from Woodbury's research, that
many traditional neognath clades (including Gruiformes, Columbiformes
and Piciformes) are not monophyletic, looks like it's to get
increasing coverage in the near future: Woodbury's _Proc. R. Soc._
paper includes references for at least 5 papers currently in
New dromornithid material has just been announced - apparently
complete skulls and skeletons indicate an affinity with anseriformes.
Julian Hume, who recently returned from Hawaii, was telling me this
morning about the several new subfossil anseriform taxa currently
being described. The English language does not do justice to the
abberancy of some of these forms: imagine crossing _Ornithorhynchus_
with _Anas_ and you might get the picture. Julian is working with
Storrs Olson on a book about Mascarene birds, and recently
presented (in an NHM talk) new data on some of them: unfortunately
this didn't make it to the press while the stuff in the following
talk - about thin-shelled Mascarene giant _Geochelone_ - did.
Imaginative journalists spout nonsense about these animals being
'racing tortoises'.. sigh.. this is missing the point.
BBC's _Horizon_ episode on birds was quite good I thought, bar the
computer animations. _Caudipteryx_ whirred and clicked like a
clockwork toy and had the head of a fish. An arboreal _Archaeopteryx_
chomped lamely on a dead grasshopper while its flat grey fish-eyes
looked up and to the side. Meanwhile, Feduccia was brilliant and
showed that he really isn't budging once inch: theropods are still
too big, and with just 'too much baggage' to become birds, plus it's
just 'almost inconceivable' than feathers could evolve except as
fully formed and for flight. Convincing stuff. Not.
Scientists tell us that the Earth goes round the Sun. But any idiot
can see that the Sun revolves around the Earth!
Get the point?
Another disappointment: the Chinese fossils. Though we saw lots of
Chiappe and Norell peering over _Caudipteryx_, not even an expert
could make sense of the messed up fossils. BBC would have done well
to superimpose an outline drawing onto the slab. One item of
confusion was that it was explained how _JP_ erred in making
little _Velociraptor_ into a gigantic _Deinonychus_-sized monster.
Err.. doesn't everyone know that the _JP_ '_Velociraptors_' are
actually deinonychi? That is, Crichton and Spielberg follow Paul
While I am writing this email Dave Martill is babbling about the
dubious nature of _Santanadactylus_ - oh, a new _Tupuxuara_ specimen
(complete skeleton) has just been mentioned. On the subject of
rumours, everyone should stop talking about a certain
integument-bearing dinosaur from the orient NOW. Publication is being
jeopardised. But that's just my opinion. I'm looking forward to
Bakker's description of a feather-bearing sauropod - it's in the
works I'm sure:) And I recently attended a talk by one of Susan
Evans' students where one slide showed a prosauropod ilium 4 mm in
length. Yes, that is not a typo.
Onto mammals. Szalay and Schrenk (1998) have just had a very nice
_Kaupia_ paper published on _Eurotamandua_ and 'edentates'.
_Eurotamandua_, as everybody now knows, is not a xenarthran, and is
now given it's own group: Afredentata. Kielan-Jaworowska and others
assert in _Lethaia_ that _Ausktribosphenos_ is not a tribothere, but
a sort of unusual symmetrodont. This is very interesting view.
On a side note, Darren is in the process of becoming married, so when he
gets back in cyberspace, we should all wish him well!
____/_\,) .. _
--____-===( _\/ \\/ \-----_---__
/\ ' ^__/>/\____\--------
Jerry D. Harris
Fossil Preparation Lab
New Mexico Museum of Natural History
1801 Mountain Rd NW
Albuquerque NM 87104-1375
Phone: (505) 899-2809
Fax: (505) 841-2866