Cladistics and stuff

["Ralph Chapman" <Chapman.Ralph@NMNH.SI.EDU>]

Just thoughts along this line. 

I hate the idea that the dino/bird "controversy" sometimes gets really caught 
up in rather detailed discussions on exact cladistic, or perhaps better stated, 
phylogenetic, procedures, which have been used - and I'm NOT talking about HP 
Kinman here - by some as part of a long term campaign to obfuscate the real 
dialog about dinosaur bird origins. The weaknesses, and the 
pain-in-the-buttedness (technical term, for those not directly in the 
profession) of some of current phylogenetic procedures are well known to many 
of us who are racking our brains to come up with a better system, which would 
include HP Kinman, of course. I'm still waiting but am still thinking.

In the dino/bird dialog I would just settle for phylogenetic approaches that 
are just quantitative, repeatable and explicitly stated as a good starting 
point for a solid dialog. Then we can argue the fine points of which algorithms 
do what, as well as look for similarities in the results of the various 
approaches - which suggests robustness in those results - and, of course, 
differences, which is where the neat areas for developing discussion exist. 
Let's indeed experiment with all sorts of use, modification and perhaps even 
abuse of the parsimony and parsimoniesque - another technical term 8-)  - 
assumptions of cladistic approaches and see what the heck happens.

―---quick aside ―- my lovely bride Linda (Deck) and some friends were in one of 
her friends kitchen while she was in high school. They were trying to figure 
out how to cook a frozen pizza (which should be illegal in Buffalo, NY which 
has great real pizza). They were arguing how to do it just the right way, when 
the grandmother of one of the friends heard the ruckus and came into the 
kitchen and said "Just put the damn pizza in the damn oven and see what the 
hell happens!" I see great wisdom from age there. Let's just play with lots and 
lots of assumptions and see how robust things really are. See what the problems 
really are.

I just get tired of the anti-dino origin mafia giving nothing but classic, 
non-quantified or even repeatable observations in what they see as the 
phylogenetic relationships. "Oh, I have a warm ookie feeling this thing is a 
bird and it is because I say so." Sorry, this does not cut it in science, or to 
put it in feducciary terms, "Hypothesis non-existent!" so rejected.

So, let's experiment with all sorts of different algorithms and, even more 
important, let's actually pay attention and discuss the characters in detail! 
Even though I do phylogenetic stuff using classic cladistic algorithms I still 
get really sick and tired of characters that go like -

orbit not round but also not sub-ovate

real quality morphometric observation there (whatever face thing means 
sarcastic should be inserted here). I really think lots of cladists reject the 
use of detailed morphometrics because they really know that many (hopefully not 
most) of their characters will really end up being continuous blobs if actually 
studied with some morphometric intelligence. I think the great part of Hutch's 
recent 2 papers (great papers in my first read) is that he really concentrated 
on the functional/developmental implications on characters, what really were 
different characters. We should be doing that with morphometrics as well - 
although Miriam Zelditch and Bill Fink have been leading the way here and 
should be congratulated whether you like their specific morphometric techniques 
or not.

So, if someone is not willing to be explicit and quantitative and repeatable 
they really have nothing to say in this dialog except just another intuitive 
opinion. If someone is not willing to expose their characters to real 
heavy-duty analysis they are in a similar boat.

RANT - The next time I hear someone give a single ratio value as the break in a 
character distribution, I think I'll scream. Almost all bivariate distributions 
have ratios that change throughout ontogenies (unless they go through the 
origin and are linear, which is very rare), and many taxa share the same ratio 
at some time in their growth. The power is in actually looking at the bivariate 
relationships, the occupation of the morphospace - not the ratio. - 
END 'O RANT

Anyway, let's take this discussion away from the warm ookie belly feelings and 
just get it to real quantitative discussions. Frankly, I don't care if someone 
wants to use Dinosauria as excluding Aves as long as he/she is doing a 
thought-out phylogenetic analysis of some sort and they are explicit about what 
they mean. If an anti person has an analysis of coded characters - explicitly 
stated - that are phylogenetically reconstructed using some algorithm - and 
this is a broad term - that I can sit and do myself at my desk, then we can 
actually have a scientific discussion. the rest is just a discussion of the 
qualtities of the data and algorithms and that can be progressive and 
constructive. Sure beats wearing a girdle around both your shins and waddling 
around and thinking something scientific is actually happening regarding the 
bird/dino debate (semi-cryptic reference here).

And if the hair on pterosaurs (at least the one) is the same as dino fuzz, I 
would be just delighted because it would really be fun and be a very 
interesting and mischievious thing. Would not expel the dino/bird origin 
theory, would just drop dino fuzz down a bunch of nodes.


Anyway, remember the bird-dino origin stuff seems to be pretty algorithm robust 
and it will take considerable effort to break it. Everyone should try and do 
that, Anti-dino origin types included. the latter just need to do their job 
much better than they have. They seem to see negative feelings from most dino 
types as being the result of trying to disprove the dino origin idea. It is 
not, from me at least it is just disappointment in the quality of their 
arguments, which seems to be pretty low up to now.

Triceratops exhibit almost done (2 weeks left) and I'm going insane, which is 
probably apparent from this post. Bruce Mohn did a construction of the old 
mount using the miniature bones we generated that is to die for! Bob Walters' 
art is wonderful. We also have some bronzes of the miniature head that also 
make your heart go pity-pater as well. Bought a tux and am looking forward to 
creative black tie and removing a larger than big ungulate sized monkey off all 
our backs.

Ralph Chapman



Ralph E. Chapman
Applied Morphometrics Laboratory
National Museum of Natural history
ADP, EG-15  NHB, 10th & Constitution, NW
Smithsonian Institution
Washington, DC 20560-0136
(202) 786-2293, Fax: (202) 357-4122
Chapman.Ralph@nmnh.si.edu