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>>But IMO that doesn't mean old-fashioned two hundred pages long monographs
>>careful anatomical description should be replaced by short Nature or
>>papers with almost nothing in them and some unreliable sixty taxa tree at
>They haven't been. We still get long monographs (Clarke's on Ichthyornis,
>Chure's upcoming on Allosaurus, etc.), and short papers existed in the past
>too (ever seen any original descriptions by Marsh?). It just takes longer
>to write long papers, and I for one would rather learn about a new
>quickly than wait several years for a monograph. Monographs are often
>published for specimens originally described briefly anyway.
I must admit that when writing my original mail and thinking of those
wonderful old monographs, I was briefly stricken with the "it was better
syndrom, which should ever be avoided, even by paleontologists. :-) But the
fact is that, as far as I know, not one of the recent discoveries (let's say
fuzzy ones from Yixian) has been correctly described, and we're already
building heaps of trees including these taxa. Of course new discoveries should
reported as quickly as possible, but am I really wrong when I say that short
and superficial descriptions are more and more frequent. Well, maybe it's
just me, or maybe it's because we find more new species and have too little
time to do the job really well. Anyway, I remember talking to Gilles Cuny when
was younger and dead convinced that I would become a paleontologist: a VERY
pessimistic guy about his work, he pointed to me that NO significant
monograph had been published in the last 20 or 30 years (that was just before
recent bunch of them). That was a slight exageration (what about Baryonyx and
Massospondylus, must have I answered), but I suppose the trend he was hinting
at is not pure fiction.
>>But I dare to think
>>this is NOT science. For me, dinosaur paleontology is mostly anatomy,
>>stratigraphy, paleobiology and paleoecology. The first two items are the
>>dry and hard
>>data on which the other two more attractive ones are based.
>>But where does phylogenetic systematics fit in there?
>Phylogenetic systematics is as much science as paleoecology is.
Yes, or maybe more, paleobiology and ecology being largely based on
speculation as soon as they intend to be precise (what I have in mind is, for
example, the debate about T. rex as a scavenger or not). Phylogeny definitely
science. Crappy analyses aren't, just like bad paleobiology isn't.
>just determining different kinds of facts. You may find the higher level
>subjects to be more attractive, but not everyone shares your aesthetic.
Oh, I don't really think phylogeny is less interesting than anything else
paleo-related. When I was younger I was fascinated by cladistics and
phylogenies, and would have made a reasonably good cladistic fundamentalist
crusade against other points of view. Now that I have studied many other
than paleontology, a little smile tends to appear on my face when I see people
arguing about where exactly does some fragmentary specimen fit in the
>>I completely support
>>Nick's position in that I think we should mostly limit phylogenetic
>>to the identification of solid patterns (with or without postcranial
>>characters, that's not my point). But after this is done, I can't see the
>>utility of those numerous analyses. You add some abscure species known
>>teeth and one caudal vertebra and the tree gets completely changed... Get
>>of some characters you don't like and Corythosaurus might appear as a
>>new ankylosaur! I'm not exagerating so much.
>From your description of the labile nature of current results, it should be
>clear identifying basic evolutionary patterns is NOT complete.
Agreed. But out of ten analyses, how many do really contribute to a better
knowledge of these patterns? I feel that having a tree at the end of your
paper is not really enough to make a valuable contribution to phylogenetic
>published morphological cladistic analyses are crap. Too few characters
>taxa, too subjectively defined states.
Yes, that's exactly what I was saying. I love cladistic analyses, when
they're good. The time used to make the crappy ones could be used to better
the anatomy of the critters they're trying to classify, no?
>Once adding a new taxon or getting
>rid of a few characters doesn't change topology much, THEN you can complain
>we should get on with other fields.
I will. :-)
>OR I could reverse your argument. Once we get the basics of paleobiology
>down, let's move on to determining low level relationships. We already
>Tyrannosaurus is a terrestrial carnivore, I can't see the sheer utility in
>all these papers trying to determine its speed, cranial strength, binocular
>overlap, etc.. You change some assumptions in Hutchinson's running model,
>and come up with completely different results. ;)
Point taken. However, even if it is very tricky and largely based on
speculation, if I had to chose, I would better learn how T. rex behaved as a
animal in a living environment than whether Daspletosaurus is more closely
related to it or to Gorgosaurus. I don't expect everybody to share this
aesthetic, as you say, but I do expect not to be the only one...
>>I keep thinking that human
>>thought is somewhat superior to computer calculations, and that careful,
>>anatomical studies completed with detailed stratigraphic work can also
>>some useful picture of evolution. I think we'd know more about bird
>>REALLY describing ANY of those Yixian feathered findings than by building
>>heaps of cladistic trees by slightly modifying some already used and
>Human thought is inferior to PAUP when it comes to calculating most
>parsimonious trees in a realistic time. All the anatomical description in
>the world is useless for phylogenetic studies if objective extensive
>comparisons to other taxa aren't performed. Madsen's monograph tells us
>what Allosaurus' osteology was, yes. But does it tell us how and why
>Allosaurus is related to Acrocanthosaurus or Carcharodontosaurus? Okay, it
>technically does include a page of comparison with some other theropods,
>you get the idea. We need both detailed descriptions and extensive
>phylogenetic analyses (and other studies...) to learn about the totality of
This is fine for me, but... I get the impression than most published
analyses are somewhat hiding behind the fact they were calculated, by a
you include a thorough description of characters used, coding methods, etc...
and seriously discuss the results (concordance with fossil record, and the
like), then using PAUP is perfect. Just stuffing some unjustified matrix into
it and publish the result is not.
>>think we might figure out many things about phylogeny if we started
>>about it instead of having computer programs do the work for us.
>>Is it that silly to say that we could somewhat turn back to
>>actually thoroughly interviewing fossils instead of comfortably use some
>>unreliable statistical method?
>PAUP only does work we could do ourselves if we weren't so slow. We don't
>use parsimony because it's easy, we use it because it's objective. That's
>what makes cladistics more scientific than non-quantitative methodologies.
Well character definition is not that objective. Or it would be if we had an
absolutely complete picture of the organism including ontogeny, individual
variation and the like. But since we don't... Basically, as I understand it,
using parsimony is saying "there 51% chances that tree A is the right one, and
49% that it's tree B, so we'll accept tree A". Evolution acts on the whole
organism, not on separate parts of it; I always feel like determining a NUMBER
of shared characters involves a reasonable amount of cheating with logics.
>Is morphological cladistics unreliable? Perhaps. I seriously doubt a lot
>of our classic theropod relationships are real, for instance. But at least
>we have a consensus. And I'd rather have that than unresolvable 'which
>character is more important' debates any day.
The consensus is useful for systematic purposes, but it could also be used
as a hint at what we should look for in fossils. PAUP tells tyrannosaurs are
coelurosaurs. Okie. Let's look again at those tyrants and redescribe them AS
coelurosaurs, just as we previously described them AS carnosaurs (subjective,
yes, but important). Our knowledge of phylogeny should, I think, come from a
dialogue between computer experiments and thought, not, as it sometimes does,
only from calculations.
>>And, more generally, is it really more
>>interesting to know where Torvosaurus fit on the cladistic tree than to
>>know what it
>>looked like and how it lived?
>To me, yes. Yes it is.
- Re: Resending
- From: Michael Mortimer <email@example.com>