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Re: Give us a Break
I would let Nick answer this first, but feel I must 1) defend
a person I'm familiar with and was probably making a point
without being ultimately serious [correct me if I'm
mischaracterizing you, Nick], and 2) make a distinction between
two zoological practices. Also please note that I seldom address
messages _to_ someone in the sense I am now.
First, Nick was using the term "class" in the sense of a
reference point, he was not ranking anything. This is the same
sense I use it in when I talk to you.
Ken Kinman (firstname.lastname@example.org) wrote:
<I certainly hope you are kidding. Sounds like
Crown-group-mania. A separate Class for turtles?>
No. Not. Turtles could be anywhere in the diapsid tree or out
of it. They are certainly not resolved. Nick was making an
observation that there are six distinctive and well analyzed
extant taxa that can serve as reference taxa in greater
phylogeny. A node-defined Tetrapoda could be an all-inclusive
specified sextet of these taxa.
<And do you know what a caecilian looks like?--->
I do. I know Nick does. I also know that it is irrelevant what
an animal "looks" like, because anatomically, caecilians are
lissamphibians. He was offering this because Amphibia and
Lissamphibia have baggage, and what better thing to do than
resolve the clade? He's also advocating regular suffices for
concept-based taxa that you should not have too much trouble
recognizing (no insult, meant formally as in recognizing a taxon
as a member of a clade).
<Do ornithischians look more like birds or beasts (and is a bat
more beasty or birdy-looking)?>
Ornithischians look like nothing. Specific ones can look like
something. They also evolved, purportedly, from predaceous
archosaurs. Descent matters. That the main lineage of dinosaurs
stem from and live now as primarily predaceous animals, who as
George and Paul note, become increasingly "avian" in form,
irrelevant that side lineages look nothing like birds. An
example is that pterosaurs look nothing like sharovipterygids,
yet there they are, sister groups, and one appears to descend
from the morphotype of the other.
<What about ichthyosaurs (neither snaky nor birdy).>
Ichthyosaurs are like turtles, they jump around the reptilian
tree too much, even outside it. They will be placed closer to
their most recent living relative than others. That's their
<Not to mention that -opsida is the ending botanists give to
And here's the crux of the issue, I take it. Nick is a
linguist, and was using the term -opsida to formulate his suffix
in the etymological sense: "the appearance of" or "the like of"
as in reference to relationship, not in comparing the color of a
pigment. Or the facial features of *H. sapiens* races. I look
Caucasian, but so do some non-Caucasian races. In fact, you'd
have to trace my ansectry to determine my true race, which is
questionable (I am not pure Caucasian, or of even one European
ethnicity). It is irrelevant that botanists use a relative term
for similiarity to formulate their suffix.
<There is nothing wrong with four classes of tetrapods
(Amphibia, Reptilia, Aves, & Mammalia), except that the first
two are paraphyletic with respect to those that follow.>
Here's the second part of the reason why I'm posting ...
1) Amphibia is apparently paraphyletic, as some classic
amphibians are not even tetrapods, tetrapodomorphs, or are
closer to amniotes than "true" amphbians. The amphibian group
which comprises a holophyeltic whole is Lissamphibia, and even
this may be paraphyletic. No one has a problem with this. The
term Amphibia being used to designate a formal clade is similar
to Thecodontia being a collection of disperse archosaurs that do
not form a holophyletic whole and are, in fact, polyphyletic. In
the sense that amphbians in the vernacular gave rise to reptiles
is true, as is the sense that they gave rise to mammals, and
reptiles to birds. Formal designations when taxa where thought
immutable are all and fine, but life is not so perfect and
simple to but into discreet groups and to restrict them so is to
deny the ability to recognize and formulate groups which
demonstrate a more evolutionarily and descent-driven paradigm
that has been recognized for a hundred years and is advocated
even by Ashlock and Mayr, and yourself.
<And of course, that is the primary sin of cladistic
2) Religiosity refers to a condition of institutionalism of a
spiritual faith. I would recommend not using it here. However, I
understand your intent in using the term.
3) Cladistics is the mathematical process from which are
derived numeric-based trees suggesting reltionship derived from
a matrix. Posts to the list clarify this further. Phylogenetic
taxonomy offers positions on holophyly and paraphyly, thus the
term PT or phylogenetics should be used in leiu of cladistics in
<Pardon me if some formal paraphyly or impure Latinization
offends the purists, but I'll take fewer names, greater utility,
relative stability, and a little common sense any day.>
Any progress on determining the rules to emmendations?
<Thank you Benton, Dodson, Cavalier-Smith, Mayr, and Ashlock.
They, most biologists, and the public that support your work,
all cry out to the pure cladists:>
I mean to be as least aggressive in this: would it please you
to ask these individuals to write on this themselves? And the
general multitude listed as "most biologists"? Making a number
like this is not science, if to support your clause as being
overwhelming to the opposition that they must bow. There is a
saying: "Those that speak in terms of generalities choose not to
grasp the specific, for whatever their reasons may be." I'm
Appologies if I've offended you, Ken, for my intentionally
non-aggressive but annoyed stance (admitted) or Nick for
usurping his post.
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