Re: BAD vs. BADD (was: Re: Most popular/common dinosaur misconceptions)

["Jaime A. Headden" <qilongia@yahoo.com>]

Jura (pristichampsus@yahoo.com) wrote:

<I?m afraid I don?t quite get what you are saying here. Why is it okay to call
a bird a dinosaur, but it?s not okay to call a snake a lizard? Especially when
you seem to be in agreement with Pianka & Vitt on just that, further down in
the post.>

  A lizard, unfortunately, entails the idea of a sprawling legged animal.
Although it is technically correct to refer to snakes as "legless lizards",
which is true almost of moasaurs as well. Additionally, birds are in most
respects flighted dinosaurs, since there are no flight-worthy dinosaurs
(powered, that is) that are not also thought of in some way as birds, from
*Archaeopteryx* or *Ichthyornis* to *Anser* or *Passer*.

<As for Linnaeus, I don?t see the point of using him as a counter example. He
did a lot of good things for taxonomy by giving us a classification system that
works (and IMHO still works far better than phylogenetic nomenclature). Other
than that, though, he got everything else wrong. He included sharks as reptiles
for crying out loud (all under one of the first wastebin taxons: Vermes). That
his understanding of the relationships among creatures was?lacking, should not
come off as a surprise. Back then, all of this was new.>

  Which is why change should come naturally. The greatest opposition to change
to the system is unfamiliarity, as Linnaeism (the system, as different from the
man, since the system has evolved since the man into something he did not
likely expect -- as evidenced from his constant changing of the system during
the editions of his volume) provides as its basis a typological framework of
differentiation, using similarity to join taxa only by passivity. It is
similarity, rather than dissimilarity, that Linnaeus himself might object to,
since it was less understood than typological differentiation was to people
making discrete "units" of life. At what point is the rank system logical,
since it provides no actual means of adhering itself sceintifically? It is a
system of "taste," and neither logical nor scientific in the least. Science
would do itself an honor and service to abandon the rank and file, as it were.

<Just because the initial change from theropod to _Archaeopteryx_ was small,
doesn?t mean that labeling that spot as a nomenclatural splitting point, isn?t
useful. From Archie (presumably), birds went off in a completely different
direction from dinosaurs, and became wildly successful at it.>

  Actually, "from dinosaurs" is illogical, as I see it, since a direction
"dinosaurs" were going has not been specified. Before *Archaeopteryx*,
evolutionarily, dinosaurs (meaning maniraptoran theropods and arguably before)
were exploring arboreal and likely volant life before the morphological changes
resulted in a highly succesful arboreal and volant group, but no less a
subgroup of Dinosauria than Theropoda itself. Our familiarity is strengthened
by the survival of this small animal over the remainder, but this makes them no
less a special case than those which died. Should living whales by extension be
split from their ancestors, or bats from the non-batty ancestors, the
non-chiropteran mammals? No, it seems hardly likely you would, but as you have
not responded to my comments on bats above, I will re-state it:

  There are MORE differences between bats morphologically (and apparently
genetically as well) and any given ancestral stock than between *Archaeopteryx*
and any maniraptoran that is also not an avian. Indeed, between *Archaeopteryx*
AND, say, *Confuciusornis*. That there is no metric for this difference, yet
one is easier to claim because the separate is more obvious and more entrenched
in the human awareness than the other. Bats have been mammals for over 200
years, birds have not been reptiles (or recognized by most of the scientific
community as dino-descendants) for hardly two decades.

  It is this issue that I have pointed out to, I think, more than any other,
and the reason also that Linnaeism has a stronger hold: It is more familiar,
and its loss one that inspires fear. Also, the alternatives offered have
substantive change, including our beloved rank and file. With all change comes
fear as one leaves the known behind and looks into the unknown, and this I see
all all of this. But the new only seems to require bravery -- a challenge.

<This is like how snakes went in a separate direction from lizards, and became
highly successful at it. Separating serpents from saurians has proven to be
very helpful, and still no one denies that snakes evolved from lizards.>

  Indeed, as no one denies birds evolved from dinosaurs. But these terms come
from the Linnaean separation of ancestor and descendant as equivalent entities,
an artifact of its flawed classism, that a descendant, if peculiar enough, can
become "special," even if the chain of development is so minor as to be one
change between each ancestor--descendant pair for a million years.

  Now, as for birds: Exactly what IS the cutoff determination for "Bird"? What
does one qualify as the break between "Dinosaur" and "Bird"? For "Snake" and
"Lizard" this seems easy, until you find legged-snakes and mosasaurs, but for
birds, people usually start with two familiarities: *Archaeopteryx*, or living
birds. Why the former, but not, say *Rahonavis*? Or why the latter, but not
*Ichthyornis*? These differentiations are illogical, and again, as I said
above, are suited to taste alone.

<Cetacea never evolved from Mammalia. It evolved within Mammalia. I don?t think
there was ever any real doubt that whales were mammals.>

  Birds also evolved within dinosaurs, and snakes within "lizards". I don't see
the difference here, but clearly my use of the relationship has managed to
catch this logic flaw. What woudl make birds and snakes so different, the
typology?

<How is using a separate set of nomenclature for birds and dinosaurs (as was
traditionally done prior to the 1990s) worse? Why is a hypothetical cut-off
point so hard to accept? Especially, when accepted hypothetical boundaries
abound in other fields of science (more below).>

  Just as using a separate set of nomenclature for zoologists, anthropologists
and veterinarians an illogical approach. Attempts to integrate the disciplines
are usually rejected through referrences of "convention" and "familiarity."

  And the question is, WHAT hypothetical cut-off point? Certainly one everyone
can agree on? Define "Bird" and then define "Dinosaur", and tell me why one
can't be another.

<None of those are comparable examples. All are sub-members of the groups you
mentioned.>

  But this is PRECISELY my point. Birds ARE submembers of dinosaurs (in the
vernacular), just as gharials are subgroups of crocs. That some people quibble
about the specified use of "croc" ONLY for crocodylids while others (many
others) use it for the entirety of croc-like animals, and many croc-researchers
for the crurotarsans and crocodylomorphans (or just plain Crocodylia).

<Fundamentally this is an issue about ranks. There is a general disdain for
ranks from cladists (and most active members of this list), simply because the
determination of the rank is an arbitrary one. For whatever reason there seems
to be this view that if it?s arbitrary then it?s useless scientifically.>

  Science is about what again? Arbitrarily, I could ignore everything you said
and say you were wrong, and never have to prove a thing. One can say the sky is
green, arbitrarily delcaring this to be so, and I could say purple -- and why
would we do so? No reason, but it's easy to communicate, no?

<This makes no sense. The basics of so many aspects of science are arbitrary in
nature. Look at SI units such as the meter. Prior to its ties to light, it was
once measured as the distance between two engraved lines on a platinum-iridium
bar. Before that, it was measured as 1/10,000,000th the distance from the
equator to the North Pole. Talk about arbitrary.>

  Yet the need to refer to a distance began, as the AU arose from Earth's
distance from the Sun, from a need to measure things objectively. The measure
of a distance by a concrete, unchanging distanct meant that this distance could
be communicated without variation. Removal of "taste" and entrace of
objectivity. Yet one has to agree to this use for it to work. Do you? If not,
then you have arbitrarily decided to NOT use it and to use some other. Maybe
the cubit (arbitrarily, the Biblical measurement can be useful as a tie to
Middle Eastern archaic scales!).

<Their fundamental properties may be arbitrary, but the proportional
relationships garnered from them, are not.>

  But notice what those scientists were doing: The need to measure things gave
them drive to bring about objective reasoning. The timing of Cesium decay, and
the measuring of a second by consequence. A "Class" has failed to find
objective reasoning, just as a "Family" has. Not so "Genera" and "Species",
which have been attempted to be quantified by gross genetic changes (difference
of gross nucleotide sequences) and the ability to interbreed (which is still
fraught with problems such as some "species" inability to cross with species
other species they CAN cross are complimentary capable of). Yet these systems
are only viable when attached to taxa, which taxa are viable enough on their
own to "ensure" their organization through definition, or allow their intent
(their content, actually) to ensure their applicability; this leads to the
problem of redundancy which, as nature should teach us, is ripe for mutation.
Duplicates of genes are transformed in time, after all, and no two animals of
an indentical eco-morphotype can coexist without out-competing the other. 

<It just places invisible boundary points to allow for our brains (which seem
to need to categorize things) to better grasp the material.>

  Where ARE these invisible boundary points? How does one find them? When can
one recognize one if he finds it? Why can't I change the boundary as I see fit
(arbitrarily)? What defines this boundary, even: Whay does it represent? Do you
see what I mean by unscientific systems? This is what led to people trying to
make concrete the metric system (using the rather solid rule of exponents by
tens, rather than the Imperial system America is still using).

<My point is that we don?t go around calling colours things like non-green red,
or non-violet infrared. All it would do is make things confusing.>

  Yet what you call "red" is not the same as a "snake". There IS a spectral
definition somewhere for "red" and it is arbitrary, but the colors that appear
between its limits are what most call "red". Yet where "red" ends and "purple"
or "orange" begin are very arbitrary, as the names of the colors are. However,
once can have "non-cerulean blue," and "non-lemon yellow", but without
definitions to declare the differences, these are largely meaningless
scientifically. Scientifically, one can define a frequency range and gain
definition.

  Cheers,

Jaime A. Headden
http://bitestuff.blogspot.com/

"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)

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