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Re: a rose by any other name(was fish & dogs)



Mind if I begin with a compliment?
You write cogently, you understand the prior argument, you respond directly,
the information you introduce is pertinent, and your arguments reach
conclusions related to the topic.
You might have been an English major.

I said:
<Simply, the majority idea is that birds are very different from anything
else extant, and 'deserve' to have a separate designation.  The resemblance
to comparatively
obscure dinos can be considered more an evolutionary history issue than an
essential element of grouping.>

and you responded:
<But what if you use a grouping scheme whose binding principle IS
evolutionary history?>

Then you would be correct within your premises in saying 'birds are dinos'
and 'non-avian dinos'.
I was observing 'the majority idea', that what establishes a group is
diversity and widespread representation.  Dinosaurs are a group that lived a
long time ago.  The two secure facts about dinos popularly is that they were
big, mostly, and they are extinct.  (The other interesting feature about the
majority view is the co-existence of the image that dinos were awkward and
stupid, dying out for that reason, and the Jurassic Park image of quick,
lethal animals killed from space.  Try to get through a business article
about AT&T or some other old company accused of being slow to respond
without seeing the word 'dinosaur'.  The continuation of the hapless beast
idea is the everyday version of a legal fiction.  But that's another topic,
living here only in parentheses.)
>From the popular point of view, then, dinosaurs are a major group like
amphibians (and reptiles), but died out, and birds are another major group.
In other words, group definition based on observation of numbers and
spectacular diversity rather than evolution.
So, the thorough application of logically consistent ideas produces an idea
of birds strongly at variance from the popular idea.  Do you
-stick to principles or compromise by carving birds out of dinos (and dinos
out of reptiles, another parenthetical ghost),
-and if you stick to principles, do you attempt to persuade the public to
agree with you, or acknowledge the popular approach when speaking to the
public, but use the different logic within the field?

Then, in your courteously responding to my questions about cladistic logic,
you note:
<These problems CAN be controlled if your taxonomic scheme uses some sort of
organizing principle that can deal with the otherwise-fuzzy margins.>
(but) then go on to add:
<Any time you get near the base of a well-known lineage there is some
question as to whether a particular taxon belongs in that named group or
not.  (This is less problematic if the taxonomic scheme has rigorous
organizing principle, and more problematic when multiple (or no) organizing
principle is used).>
Less problematic, then, but still problematic, as shown by your list of
examples and the endless discussions of the coding and relative significance
of characters of basal whatnots here on the list.  If the greatest weakness
of a classification system which carves out groups of species (I know, but
taxa are right up there with bosons in public understanding) based on
obvious differences from other species is fuzzy examples at the margins, if
that's the controlling argument, then the superiority of a phylogenetic
taxonomy is a very fine distinction, uncompelling for marketing purposes.

You did confuse me a bit when you said:
<This [one can test whether a critter belongs in a taxon or not] is also
true for systems that might use a particular suite of defining (rather than
merely diagnosing) traits: if the critter has these traits, it is a member
of that clade; if not, it ain't.>
The distinction between defining and diagnosing...
Also, implicit here is that the identifying information is primarily based
on observation (has traits/does not have traits) rather than history (is
related to _because_ the animal has certain traits hypothesized to indicate
an evolutionary relationship).  Once you have said observation is acceptable
in classification, and suites of related traits do also bring in function
and other non-historical judgments, then are you far from saying birds are a
recognizable group?

In fact, being facetious and taking a comment out of context, doesn't
saying:
<...[Aves] is the clade comprised of all descendants of the most recent
common ancestor of living feathered
vertebrates, in which case the Mesozoic taxa I listed are NOT birds...>
match the popular definition and resolve the fuzzy examples problem,
assuming Aves were at the level of Reptilia?

I'm also trying to catch up with your meaning when you say:
<Would Prof. Big (who may be dead, making him difficult to reach) include
_Nova taxon_ in his Taxomorphoidea or not?  Do we expand Taxomorphoidea to
include it, or create a taxon of equivalent rank for it, or what?>
then note later:
<We could argue whether "bird" technically applies to the clade Avialae
sensu Gauthier ... or if "bird" applies to Aves sensu Gauthier ...>
it sounds like Gauthier is equivalent to Prof. Big as far as Avialae/Aves is
concerned.  Does having algorithms really eliminate the existence of sensu
somebody?


Okay, I admit it, when some Teachers watched me come to the front of the
room after a lecture, that trapped animal glower told me they'd be making a
beeline for the door before I got there.