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Princeton Field Guide



Now that the field guide is out and about some comments. 

The book is a POPULAR work entirely in the style of a field guide for birds 
or mammals. So it does not include specimen numbers, diagnoses or the like 
and I donât want to hear about it. It was enough to get the project done as 
it is what with all the illustrations. The anatomical descriptions are of 
the informal nature seen in field guides. A technical book with specimen 
numbers, diagnoses and the like would be a very different, more massive and bar
ely sellable work, and require far too much work. Even a version of PDW 
expanded to all dinosaurs would be massive and unsellable in the trade market. 
(As 
it was Don Glutâs encyclopedias made doing the book vastly easier than it 
otherwise would have been.) 

While doing the skeletal restorations I found that in order to avoid doing 
chimeras I had to separate overlumped taxa which contributed to more 
revision of species and genera than I expected. Overall I was shocked with the 
pathetic state of dinosaur taxonomy, which is a scandal that is going largely 
ignored (Paul Upchurch and I were talking about the problem at the conference 
in Salas Spain is Sept, which was very pleasant affair including the dinners 
at 10 PM, the last in a private smokehouse; Jim Farlow was especially 
pleased with the abandoned church on the ridge overlooking the spectacular 
valley 
as the moon rose where a Good, Bad Ugly scene was shot). Long standing, 
major dinosaur taxa such as Allosaurus, Diplodocus, Stegosaurus, Ornithomimus, 
Struthiomimus, Ornithomimus, Troodon are based on air, and are in desperate 
need of revision. And donât get me started with what is going on about all 
the stuff being tossed into Mamenchisaurus and Omeisaurus. I put in an 
abstract for an SVP talk but they reject me every year these days (more on that 
later). There are some interesting problems that have me scratching my head, 
such as the Triceratops/Torosaurus thing. I made some suggestions but we will 
have to see what the stratigraphic work indicates (as per the upcoming SVP 
presentation). 

Concerning the latter, I tried to avoid the simplistic tendency to assign a 
species to a formation when it is now known to be from a particular level 
of a formation. For example there were a series of faunas in the Morrison 
that took ~8 million years to be deposited, with A. fragilis, D. longus and 
probably S. stenops are known only from the lower sections, and B. altithorax 
from the middle (the skull from the lower Morrison is probably a different 
taxon). The Carnegie skeleton always placed in D. altus is almost certainly 
not that taxon since it is considerably in lower in the Morrison than the 
incomplete type. There were series of species in the Dinosaur Park Formation. 
The AMNH S. altus skeleton from Dinosaur Park is almost certainly not altus 
since it is probably younger than the type from the Oldman. 

There are a few properly handled dinosaur genera that include a normal, 
large number of species such as Psittacosaurus, Apatosaurus (some species not 
yet named), Diplodocus (ditto). But dinopaleo has gotten into the bad habit 
of usually making almost every species into its own genus. This is illogical 
considering that many modern bird and mammals contain large numbers of 
species â Varanus (now formally includes Megalania), Panthera, Felis, Canis, 
Vulpes, Cervus, Tragelaphus, Cephalophus, Ovis, Gazella, Macropus, 
Balaenoptera, 
Buteo, Falco, Anas. It is also notable that Cenozoic fossil mammal genera 
often include multiple species, in many cases extending back in time from 
current time (For example extinct species in Canis, Panthera, Varanus). Is 
there something special about dinosaurs in which even in the best documented 
faunas almost every species is a genus even when the differences between these 
taxa in a clade are limited to display structures? I see that ceratopsid 
genera are now actually being defined entirely on differences in their cranial 
adornments â thatâs a mind blowing development â when these are of course 
specific level in nature. In an SVP abstract it is stated that ceratopsians 
were evolving lots of genera when the degree of variation they are refering 
to is actually the minor specific grade. Many in dinopaleo seem to have 
forgotten that the most prolific level of evolution is SPECIATION, not 
GENUATION, 
with evolution churning out the minor variants we call species in far 
greater numbers than the larger divergences that are gathered into a genus. 
Matters have gotten out way of out hand, and when finishing the book I could 
not 
use all the pseudogenera because people would presume I actually accepted 
them (as in âeven Greg Paul agrees that Agujaceratops and Corythosaurus are 
real genera). Someone needs to call out the taxonomic madness instead of 
facilitating it (the usual names are of course noted).  

There are also a number of cases in which what are clearly juveniles 
(perhaps with some sexual variation thrown in) are being assigned their own 
genus 
distinct from their adults, this is especially true of some oviraptors and 
pachycephalosaurs. There was no way I was going to keep these as separate 
taxa. 

It cannot be overemphasized how the nested classification system is 
virtually useless for a popular field guide, it providing no graded structure 
that 
the public can latch onto. Monophyletic clade only classification is a slap 
at the public already skeptical about scientists whom they see as elitists 
who donât care all that much with communicating with ordinary folks. In any 
case the phylogenetic classifications disagree with one another so much that 
I threw up my hands and cobbled what I could together (an SVP abstract on 
how difficult it is to place heterodontosaurs relative to other ornithischians 
addresses this problem). In some areas the phylogeny reflects my particular 
views, in others I have no agenda and arbitrarily used one among the 
recently published arrangements that is available for the group. 

Despite my desire to do a skeleton for every dinosaur that it can be done 
for, a number of skeletal restorations proved unfeasible at this time. For 
example photographs of the skeleton of Jinzhousaurus are available, but as I 
was working on it unresolvable issues with interpreting some elements forced 
me to abandon the effort until better images or the description come out. I 
was reluctant to do a direct side view life restoration unless the skeleton 
was pretty well documented.  

The book would have not occurred without Ian Paulsen complaining on the 
list about the absence of a high quality field guide in early 07 and providing 
contacts so a round of applause for him. 

My talk on the book at the Carnegie Museum is 2 PM Sunday (when there are 
no dinosaur talks at the meeting). 

Iâve got something fairly big and rather shocking coming out in one of the 
major science journals in mid Oct so stay tuned. 

GSPaul
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