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Date: Sat, 12 May 2001 12:27:00 -0700 (PDT)
From: "Jaime A. Headden" <qilongia@yahoo.com>
To: PhyloCode@ouvaxa.cats.ohiou.edu, dinosaur@usc.edu
Cc: philidor11@snet.net
Subject: Re: Making Up Names _versus_ Emending Names
Philidor (philidor11@snet.net) wrote:
<Differences are objectively observed, as are similarities, no?
Nothing inherently subjective yet.>
...and...
<Is similarity a better proof of relationship than difference is
a proof of non-relationship? There's discussion today on the
list about whether a similarity is significant in showing
relationship. How would you demonstrate a greater degree of
subjectivity in working from differences than from
similarities?>
I was being spare on this phrase, I appologize: I meant that
Linnaean categorization was based primarily on differentiation,
rather than similarity, whereas it is the opposite in modern
phylogenetic classification. The relationship of two organisms
cannot be tested by the lack of features: "if it doesn't have
hair, so it can't be a mammal," etc. Animals to which Linné
could not clearly label got thrown into the mix on the few
similarities he himself could label: "birds and bats are flying
with warmbloodedness, so they seem to be clearly related..." I'm
not quoting anything.
I do consider that differentiating organisms and placing them
into a context of relationship is a flawed philosophy, based on
the above.
<You aren't surprised, though, when differentiation does respond
to a substantially different evolutionary origin, are you?>
No. I'm rarely surprised in this case because I hold no
paradigms to be true. If birds are not descdant from any
theropod or dinosaur, or whatever, I won't be surprised, I hold
it neither true nor false, but as a strict possibility; just
that this one has a greater probability of being actual, versus
the counterarguments.
Similarly, I hold that an organism is better represented in a
phylogeny if its ancestors are considered as part of the
lineage, as in
--+--amphibians
`--+--reptiles
`--mammals
where amphibians are a strict group that even at the base
organism can be separated from the base amniote. Thus the use of
the sense of amniotes evolving from amniotes would be false in
this paradigm, even if a typological "amphibian" were to be
ancestral to amniotes or the basal amniote itself and not a
member of the taxon Lissamphibia. That reptile and amphibian and
bird are vernacular and not applied rigorously, this should not
be consideration of organizing organisms. This seems more
logical than the alternative and structure founded by Linné,
modified by others.
<I'm trying to follow your underlying premises in this
discussion. Any clarification would be appreciated.>
I hope I've done some clarifying on my thesis.
=====
Jaime A. Headden
Aaaaaaaaaaaaaaaaaaaahhhhhhhhhhhhhhhhhhr-gen-ti-na
Where the Wind Comes Sweeping Down the Pampas!!!!
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