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

Re: Dino cladistics - long with requotations (was Re: Dinosaur Web...

In a message dated 97-03-10 15:33:43 EST, th81@umail.umd.edu (Thomas R.
Holtz, Jr.) writes:

<< Note that "disagreement with your results" does not equal "error".
 "Discordance", perhaps, but not "error". >>

Heh heh. From >my< viewpoint it does. Of course, I can always change my
viewpoint if someone shows me a better one...

The reason I couched my post in these terms is to get (browbeat?) people into
thinking about some of the results that cladistic methodology is coming up
with and not simply (blindly?) accepting the latest cladograms that the "plug
and chug" computers have churned out. As I've said before, a 95% confidence
level means that there's still one chance in 20 that a particular cladogram
is wrong >despite< parsimony, and if we're going to weed out any wrong
cladograms, the place to start could well be with those cladograms that, at
least at first sight, seem most outrageous. I don't think Nature is slavishly
parsimonious to the point that, say, 50 characters >must< outweigh 49 every
time; to assert this is to coin another "Natural Law" like Cope's Rule and
Dollo's Law. I also think that a few random similarities in each of a large
number of regions of the skeleton, adding up to a large number of characters,
should be given far less weight than highly specific similarities in each of
a much smaller number of skeletal regions. How to do this satisfactorily is a
vexing problem, but it is just as vexing to give equal weights to all
characters indiscriminately.

I'll reply to the rest of your (most thoughtful and interesting) comments as
soon as time permits.