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Dinosaurs in the New Millenium - Day 1



Ah!  See? I finally get around to doing things.

I attended this symposium back in December, and saw almost all the talks.

Jeff Wilson's talk was very interesting and it involved one of my favorite 
subjects - phylogeny.  He briefly gave a rundown of the Dinosaur Renaissance, 
ending with cladistics, the main part of his talk.  His talk covered over the 
"pitfalls" ("sausage" matrices and supertrees:  the remedy for both is 
apparently more characters), "targets" (areas of uncertainity, i.e. basal 
thyreophorans, hadrosauriforms, basal sauropodomorphs, titanosaurs, and 
coelurosaurs; and spatiotemporal gaps), and "directions" (differential support 
[very interesting], pattern analyses, and the rate of evolution) for dinosaur 
cladistics.

Matt Lamanna gave another of the best talks, on dinosaur paleobiogeography.  
His talk covered the different methods of analyzing paleobiogeography 
(vicariance, quantitative cladistic biogeography, and phenetic similarity 
analysis [soon to be published on, Holtz et al., in press]).  He had a very 
long list of future research directions-
1. Regional paleobiogeography (faunal associations, specifically)
2. Effects of epicontental seaways.
3. Latidunal diversity gradients.
4. Paleoclimate effects (faunal differentiation due to climate or tectonic 
activity??).
5. Paleoenvironment and distribution (habitual preferences for ceratopsians and 
ankylosaurs?).
6. Physiology and biogeography (polar [Antarctica-Australia] ornithischians 
seem to be very diverse [right Pete? Gondwanan lineage of ornithopods... sound 
familiar? just thought you'd like that]).
7. Phylogenetic reconstruction.
8. Stratigraphic refinement (more detailed dates).
9. Data synthesis.
10. Phenetic similiarity analysis (Holtz et al., in press).

Stephen Gatesy's talk was another big interesting one. It was on functional 
morphology, and it listed a hierarchy of approaches (1. qualitative functional 
morphology, 2. qualitative biomechanics, and 3. quantitative biomechanics).  
Two big ideas in the talk were- 1. most hypotheses of posture and locomotion 
are not derived from functional analyses; and 2. there are no truly 
function-neutral "anatomical position". His title is a reference to manual 
articulation, a necessary step in restoring vertebrate life is often "rubbing 
bones together" and does help see potential range of movement for the bones, 
but not the actual.  They are commitments to a "hypothesis beyond knowledge" 
and "bones are not enough". Apparently, "more constraints are needed to 
determine coordination.  To get beyond "bone rubbing", we apparently need to-
1. analyze the organism as a whole.
2. study skeletal scaling.
3. search for non-osteological constraints (footprints, ligaments, muscles, and 
kinetics).
We can take advantage of new tools to do these including- 1. phylogenetic 
content, 2. extant phylogenetic bracketing, and 3. computer graphics programs.
The future directions for this talk are- to move beyond bone rubbing, 
understanding the difference between a head and skull, the end of genus-level 
authority, more than data optimization, collaborating with and integrating data 
with other authors, looking at unexplored systems (like vertebrae, ribs, those 
things), new sources of evidence, and finding new methods of communicating 
function of hypotheses.

Greg Erickson's talk was rather long and had a very long introduction that 
wasn't really necessary (but oh well). It gave a fairly general discussion of 
growth in dinosaurs.  There was of semi-interesting information, summing up 
that the rapid growth rate of avians apparently occured within Aves.  However, 
what I don't understand is that he mentions that the growth rates in 
Conchoraptor and Velociraptor are apparently close to precocial birds (Norell 
and Curry-Rogers, in press).  It is suggested that we might be able to 
determine whether or not Nanotyrannus is a juvenile by doing a histological 
study of Tyrannosaurus rex and comparing Nanotyrannus to it.

Larsson's talk was rather long and confusing, and I started to feel a little 
squeamish from not eating breakfast and sort of drifted off, so I can't comment 
much on it.  It went into overtime. Then we all went to lunch.  The food there 
wasn't too expensive and was pretty good.  During the lunch break, I was able 
to look around briefly in the collections and saw a few things of interest (the 
"Bison alticornis" specimen of Triceratops, for example).

When we got back from lunch, Matt Carrano presented his talk on trends in 
dinosaur body size evolution. There are no general size trends in Theropoda 
alone, but in dinosaurs as whole, they trended towards large body size. There 
are two exceptions, one is surprising, the other isn't. The unsurprising 
exception are birdlike coelurosaurs, and the surprising one were titanosaurs.

Sampson gave a good talk on function of display structures in dinosaurs. The 
others have summed it up well.

The others have also summed Rega's talk fairly well also.

Barrett's talk was fairly general, and covered feeding adaptions in 
Ornithischia and Sauropodomorpha, mostly it seemed.

The first day was overall very good. I noticed in general all the talks seem to 
advocate collaboration between different fields of research in order to gain a 
more accurate picture of Mesozoic life.

It was really nice meeting the people that were there, and not just the 
speakers, but also Mark Norell, Jim Clark, Mary Parrish, Mike Brett-Surman, 
Jack Horner, Ben Miller (a young paleoartist), and Greg Paul (even if was just 
a handshake).  Everyone was really friendly and overall, the entire event was 
enjoyable.  I sincerely hope the museum considers having another one next year.

I'll try to comment briefly on Day 2 later, if I can think of anything that 
hasn't already been said.

---
Nick Gardner
Aim s/n Eoraptor22

"Pinky, are you pondering what I'm pondering?" 
"Wuh, I think so, Brain, but if we didn't have ears, we'd look like weasels."


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