[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

RE: Resending

Grr... I hate Hotmail, destroying my basically complete reply. Anyway, shortened main points appear below.

Félix Landry wrote-

But IMO that doesn't mean old-fashioned two hundred pages long monographs of
careful anatomical description should be replaced by short Nature or Science
papers with almost nothing in them and some unreliable sixty taxa tree at
the end.

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 discovery quickly than wait several years for a monograph. Monographs are often published for specimens originally described briefly anyway.

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. They're just determining different kinds of facts. You may find the higher level subjects to be more attractive, but not everyone shares your aesthetic.

I completely support
Nick's position in that I think we should mostly limit phylogenetic research
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 sheer
utility of those numerous analyses. You add some abscure species known from two
teeth and one caudal vertebra and the tree gets completely changed... Get rid
of some characters you don't like and Corythosaurus might appear as a brand
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. Most published morphological cladistic analyses are crap. Too few characters and taxa, too subjectively defined states. 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.
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 know 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. ;)

I keep thinking that human
thought is somewhat superior to computer calculations, and that careful, thorough
anatomical studies completed with detailed stratigraphic work can also give
some useful picture of evolution. I think we'd know more about bird origins by
REALLY describing ANY of those Yixian feathered findings than by building
heaps of cladistic trees by slightly modifying some already used and criticised

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, but you get the idea. We need both detailed descriptions and extensive phylogenetic analyses (and other studies...) to learn about the totality of an organism.

I do
think we might figure out many things about phylogeny if we started thinking
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. 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.

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.

Mickey Mortimer