Re: ... and systematics Re: Musings on extinct Phyla

pnyikos wrote:
On May 24, 6:51 pm, John Harshman <jharsh...@xxxxxxxxxxx> wrote:
pnyikos wrote:
On May 14, 7:26 pm, John Harshman <jharsh...@xxxxxxxxxxx> wrote:
pnyikos wrote:
On Apr 30, 4:22 pm, John Harshman <jharsh...@xxxxxxxxxxx> wrote:
Notice that Romer predates Ostrom's first publication on Deinonychus,
which is what is really relevant here. The notion that birds are
dinosaurs (or are descended from them, if you like) spread through the
paleontology community at about the same time cladistics did.
Romer already flirted with it, when he wrote that if Archaeopteryx had
been discovered without feathers, it could easily have been taken for
a small dinosaur.
You're reaching, you know.
Not nearly as much as you "reached" with your True Cladophile sarcasm
below.

See quote from Romer below, and your sarcasm far below.

By the
time of Gauthier's first publication, the relationships and cladistic
classification were both probably the majority view.
So no huge change in meaning.
Romer's words in _Vertebrate Paleontology_ suggest that there was no
general consensus on which archosaurs were the immediate ancestors of
birds.
Sure there was: "thecodonts". See how useful that was?
I said "immediate" and Romer's words strongly suggest that there was
no such general consensus.
How does "immediate" change the meaning? If "thecodonts" weren't
supposed to be the immediate ancestors of birds, what other group had
been proposed?

Maybe dinosaurs, by some bold people. Romer evidently wasn't quite
that bold.

I note you didn't tell me how "immediate" changed the meaning. Romer "wasn't quite that bold" because he thought dinosaurs were precluded.

What words, specifically?

The remains, which pertain to two related
genera, -- *Archaeopteryx* and *Archaeornis*
(Figs. 209, 210) -- so closely resemble
those of some of the smaller bipedal
dinosaurs that they might well have been
taken for reptiles, were it not for the
impressions of feathers which surround them
on the stone slabs on which they are preserved.
--Alfred S. Romer, _Vertebrate Paleontology_,
University of Chicago Press, 1945 (p. 216)

Not relevant to the question of ancestry. Try a few lines later.

[snip]

No, you could give clades lots of descriptions without giving them
names. "The crown group defined via extant mammals" is just one of
many examples.
...if we want to talk about it without clumsy circumlocutions.
You have them all the time. "Stem__________" says nothing about where
in the stem or how much is included in the stem, for instance.

As it turns out below, "stem" is a redundant and misleading
expression.

It does if you know what "stem" means.
So spill the beans, already.
Stem: species outside the crown group but more closely related to the
crown group than to the crown group of any other clade.

In other words, the sister group.

In other words, no. It might be the sister group, or it might not.

So, for instance, "stem therians" are monotremes.

And "stem moontremes" are therians.

And "stem sauropsids" are synapsids.

And "stem synapsids" are sauropsids.

And "stem mollusks" are arthropods.

And "stem arthropods" are mollusks.

No. I'm surprised that you still don't understand what "stem" means. First, stem groups are by definition extinct. Monotremes aren't stem therians, because monotremes are more closely related to another crown group than to therians. They *are* that crown group. A stem therian would be any non-therian more closely related to therians than to monotremes.

And to think that all this time I thought the word had something to do
with "reasonably close to the LCA of the clade."

You have exchanged one misconception for another, unfortunately.

But I should have known better. After all, cladistic systematics says
nothing about how much or how little an organism resembles the "purely
hypothetical" LCA of a clade.

True.

Ah, the price one pays for being "objective."

The "price" is that you avoid meaningless statements and attempts to reconcile incompatible classification criteria.

[snip]

My second youngest daughter is taking a course in comparative
vertebrate anatomy, and her textbook, most recent edition 2012 [yep,
this year] is written by a non-cladophile.
Kenneth V. Kardong, Ph.D., Washington State University,
_Vertebrates: Comparative Anatomy, Function, Evolution_,
McGraw-Hill, New York, 2012.
How can you tell? Pity, if true.
You've forgotten my definition of "cladophile" as someone who will not
tolerate the use of non-clades in systematics. As I explained:
Your sarcasm below ignored the foregoing two lines.
But you knew that when you posted it, didn't you?
Did it?

Yes, or else you didn't connect the "tolerant" below with the "will
not tolerate" above, despite the liberal hint I next gave:

I've decided to stop encouraging your attempts at telepathy, so will not pursue this.

Oh, he does seem to prefer cladistic classification, but he does give
both a traditional Linnean classification and a cladistic
classification in the appendix.
See, he is very tolerant.

of taxa other than clades. Wasn't that clear from the context?

Ah, so he isn't a True Cladophile. Apparently in order to be a True
Cladophile, you have to be some kind of religious fanatic about it all.

"True Cladophile" is redundant.
Heresy!

How can an intolerance for any taxons except clades be any truer than
it already is?

I'm probably not a true cladophile, as I might be persuaded to put a traditional classification into a textbook, though I would probably say something about it being inferior to the cladistic one, and why.
.

Relevant Pages

  • Re: ... and systematics Re: Musings on extinct Phyla
    ... Maybe dinosaurs, by some bold people. ... in the stem or how much is included in the stem, ... species outside the crown group but more closely related to the ... crown group than to the crown group of any other clade. ...
    (sci.bio.paleontology)
  • Re: ... and systematics Re: Musings on extinct Phyla
    ... in the stem or how much is included in the stem, ... crown group than to the crown group of any other clade. ... And what do you mean by "the crown group of any other clade"? ... therians, because monotremes are more closely related to another crown ...
    (sci.bio.paleontology)
  • Re: ... and systematics Re: Musings on extinct Phyla
    ... in the stem or how much is included in the stem, ... crown group than to the crown group of any other clade. ... By "any other clade" I meant a clade that may include taxa outside the crown group. ... And "stem moontremes" are therians. ...
    (sci.bio.paleontology)
  • Re: How transitional fossils are determined
    ... formal is "great ape", to exclude such primates as the Barbary ape; ... Fish, I'll give you. ... A stem flatworm. ... species outside the crown group but more closely related to ...
    (talk.origins)
  • Re: ... and systematics Re: Musings on extinct Phyla
    ... in the stem or how much is included in the stem, ... just as Condylartha is now a clade that consists of a tiny ... crown group than to the crown group of any other clade. ... It's a stem amniote because it's more closely related to Amniota ...
    (sci.bio.paleontology)