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Re: BCF, BADD, etc.



GO writes:

>Hogwash. Cladists and professional paleontologists certainly
>don't care whether I believe them. Why should I care whether they
>believe me? In _Mesozoic Meanderings_ #2, I outline my method and
>arrive at a phylogeny that is at variance with their current
>phylogeny. I think cladistic methodology has some gaping holes in
>it, and that my method, such as it is, yields more reasonable,
>results, that is, a phylogeny that actually makes more sense from
>a functional standpoint. Why should I use their methods and their
>rules when I think they're flawed?

This sounds strikingly like validating your method based on the results it
produces - in other words, teleology.  You cannot validate a method by
testing it against an unknown and then say your method is better because the
results suit you - not if you want others to accept your results.

If you think cladistic analysis is producing incorrect results here you must
show why - not merely claim the method is invalid because you don't care for
the results you get.  I agree that the weakest part of cladistics is
selecting the characters, but the same is true of non-cladistic taxonomy.
If you have good reasons for objecting to the results of analyses supporting
BADD I think you must show very specifically where they have gone wrong -
and if the issue is simply character coding, then recoding and running
another cladistic analysis should give a different result.  Have you tried this?

In general, too - and please do not take this the wrong way - I think that
it is, like it or not, extremely difficult to get scientific views accepted
until they have been published in an independent, refereed journal.  One of
the criticisms I hear of Bakker around here, for  example, is that he has
his own pet journal to publish in, and this reduces the perceived
seriousness of his conclusions.  (IF I am incorrectly assuming that MM is
not independently refereed I withdraw these comments, of course).

While there is nothing wrong with self-publishing under some circumstances,
have you submitted any of your findings or conclusions to a refereed journal?

>As I pointed out before, the entire fossil record of the most birdlike
>theropods contradicts the BADD phylogeny, but this hasn't stopped
>BADD paleontologists from going on their merry way.

This is only your interpretation of that phylogeny.  Not that my opinion
matters that much but I still have not seen an argument that really
convinces me that this statement is true - and I say this with what I hope
is an open-minded attitude.  The fact that "birdlike" therapods postdate
Archaeopteryx means no more to their phylogenetic role than does the fact
that we still have living monotremes.  As I said in my longer note I do not
see why the arguments you have made cannot be considered perfectly
consistent with the view that birds and things like Velociraptor are
closely-related sister groups within Dinosauria; I still see the arm
modifications of V. as at least reasonably interpretable as functional
adaptations to grasping prey that could well have developed without a
preliminary flighted stage.  I assume BADD palaeontologists "go their merry
way" because they make similar interpretations, not because they are misled
by their analytical techniques.  Convince even an ardent cladist that the
arm structure of V. HAD TO have been derived from a flying wing and you will
have to send him/her back to the drawing board.

And I say this as one who remains very leery of cladistics as the be-all and
end-all of taxonomic analysis, because I think it tends to ignore functional
analysis.

><<Good, at least we're both being civilized here. I'd like to
>add, G.O., that I enjoy your contributions to the list (as you
>know, it wouldn't be the same without ya), and I'm not poo-pooing
>BCF because I don't want to believe it, but because I see
>fundamental flaws in it.>>
>
>The flaws you may see are not fundamental to the _method_; they
>may, however, be fundamental to _me_.
>

I think they may be fundamental to the analysis.  If what you have presented
here is a fair summary of your views, I think (as I said in my longer note,
which I'm still eagerly awaiting your reply to, but I know you are busy etc
etc) I think your underlying assumptions about the selective impact on the
way characters have evolved (or not evolved) seem central to your
hypothesis, and I find them, so far, unconvincing.  It could have happened
that way, I suppose, but I am a long way from being convinced that it had to.
--
Ronald I. Orenstein                           Phone: (905) 820-7886 (home)
International Wildlife Coalition              Fax/Modem: (905) 569-0116 (home)
Home: 1825 Shady Creek Court                  Messages: (416) 368-4661
Mississauga, Ontario, Canada L5L 3W2          Internet: ornstn@inforamp.net
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Toronto, Ontario Canada M5H 3P5