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Re: SAPE Proceedings: papers of mass distraction



Stephan Pickering (StephanPickering@cs.com) wrote:

<Some of what Jaime wrote was interesting, but I disagree with his primary
thesis of isolated bones being legitimate bases of diagnostic
extrapolation.>

  This was not my thesis, and at some point in the archives, I have
expounded on the idea that isolated bones do not usually make for
diagnoses. There are exceptions, but these require knowing the full
repertoire of that bone in the group to be able to assess an isolated
find's diagnostic nature. Some bird bones are very much like this, and
apomorphies exist within selected clades that make for determining the
phylogenetic affinities of scrap. Gareth Dyke on the London Clay, for
instance, has been working almost wholly on parts of isolated bones, and
these have some legitimacy. Some isolated dinosaur bones do the same
thing, and it is part of my interests to assess the diagnostic nature of a
single titanosaur caudal vertebra if that was found isolated. Doing this
would help. There are no other caudal vertebrae quite like that of
*Titanosaurus indicus*, but whether this morphology can exist in the
caudal sequence of another, similar animal, is not knowable. This is why I
attempt to decry identification of single or series of teeth and isolated
scrap as phylogenetically indeterminate.

>Phylogenetic systematics seeks clarity, and this does not arise from
isolated bones, however much they resemble others.>

  But it can :) There are bones that have such a high variability or broad
morphological spectrum that it is possible to determine its phylogenetic
nature beyond broad groups like "Aves" or "Passeriformes" or "Tyrannidae".
One would need to study the fossils, and comparatively to living forms,
for years before one can make any sort of assessment regarding: "there is
no way an isolated scapula can be referred to Trochilidae, absolutely no
way; why? because its just a scapula." I mean, where is the bloody science
involved in that?

<And disagreement is not belitting of anyone, but dialogue, not "veiled
insult" but discussion.>

  There are rules on a debate team about personalizing it; this is true on
this list, and it is a general policy, if not a rule, that the discussion
be about the science and not involve a person himself. Whenever I address
the list, in a response, I address the list itself, rather than the
person. I usually make an explicit statement when I choose to address
someone over the list. As if I was asking a question.

  Cheers,

=====
Jaime A. Headden

  Little steps are often the hardest to take.  We are too used to making leaps 
in the face of adversity, that a simple skip is so hard to do.  We should all 
learn to walk soft, walk small, see the world around us rather than zoom by it.

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