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

This quantum of difference is no less subjective than
the choice of characters input into a cladistic
analysis.

This does strike me as an exaggeration. For example, there is a way to test if a character has phylogenetic signal (...though it hasn't been used often).

Again, what's with all the judgements?  Why is
squamate phylogeny so 'weird'?


Sure it is :-)

I was commenting on the rather slip-shod way that
lacertilians were originally placed taxonomically, vs.
what we now know about their radiation. If you don't
think squamate phylogeny isn't a little weird, then
see Fry et al's (2005) work on venom glands being
widespread among squamates. They nest iguanians well
within scleroglossa. That's weird. Of course, that's
also molecular based.

Partly. The venom glands that make Toxicofera so convincing are good old morphology, and presence/absence of certain toxins behaves like a morphological character, too.

So these papers you mention, do they refer to annelids
now as "non-pogonophoran annelids?"

I don't know. I'm not aware of any occasion when anyone explicitely talked about annelids except Pogonophora and Vestimentifera (...together Siboglinidae).

My complaint is with the use of cladistics in
classification (i.e. phylogenetic nomenclature, as HP
Marjanovic pointed out in a prior post).

To the contrary, I pointed out that phylogenetic nomenclature has _nothing_ to do with cladistics. Phylogenetic nomenclature is a method to apply names to a tree, cladistics is the method to find such a tree. You can easily have one without the other (and of course examples of cladistics without PN are numerous in the literature, not least everything by Hennig himself).

Because it is. Cladistics started in entomology.
Phylogenetic nomenclature seems to have started in
vertebrate (dinosaur) paleontology.


That's where its first applications seem to have been, yes.

Class, order,
family and all the other ranks still abound in
entomology. So too in herpetology, and other realms of
paleontology that aren't focused on dinosaurs


PN is widely used in studies of pre-Cenozoic tetrapod phylogeny sensu lato.

(I suppose the correct "phylogenetic" term for that would
be: "non-dinosaurian paleontology").

In fact, that's a quip of the English language. It can't be translated into German, for example (where you can make up nouns at will, but not adjectives).

That snakes > are members of Lacertilia, yes

Fortunately this is not necessary, because the name Squamata is already available. We haven't been this lucky for the dinosaurs.

It used to be that bats were NOT considered
members of Mammalia, but were included with
birds by Linnaeus.

Wrong. They are mammals in Systema Naturae. (At least in the 10th edition, but judging from the characters used as diagnostic in that one, I bet it's the same in all. Remember, L. _invented_ the term Mammalia. It does not occur in his earliest works.)

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?


See above.

(and IMHO still works far better than
phylogenetic nomenclature).


How so? I see it fail every day! :-)

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).

Ah, no. Reptiles, Natantia (such as sharks, sturgeons, and lampreys), and something else are orders of Class Amphibia in the 10th edition. Vermes is another class. Though, he didn't really have to lump all crocodiles into *Lacerta crocodilus* and all salamanders into *Lacerta salamandra*, especially as some actual lizard species got their own genera, like *Draco volans*.

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. 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.

Aaah... "evolutionary systematics". The definition of "direction". Let me argue that Ceratopsidae went off in a far more different direction than all other dinosaurs, birds included, and became wildly successful at it (before their untimely end). You cannot disprove this, so we can keep arguing to all eternity.

Sure, the cutoffs of PN (phylogenetic definitions) are no less arbitrary, but at least they only work one way (delimiting a clade), not two (delimiting both a clade and its paraphyletic ancestral group -- _two_ arbitrary decisions).

Cetacea never evolved from Mammalia. It evolved within
Mammalia. I don't think there was ever any real doubt
that whales were mammals. Well, at least after it was
found that they really weren't fish. They still fall
in as mammals on morphological grounds, even if they
have evolved back to a water bound life. The same goes
for bats (the morphological thing, not the water bound
thing).


Then how can you possibly argue that the same does not go for birds? :-)

Did you mean "can't change?" Then I'd say yes, if the
incorporation only leads to confusion and the erection
of new terms to denote what the old ones mean. So I'd
say no to "non-avian dinosaur" just like I'd say no to
"non-eukaryotic prokaryote."


Well, I do think Reptilia should be abolished...

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?

Because it makes talking across it so difficult. What if I tried to describe a (speculative) fauna that contained *Jinfengopteryx*, *Archaeopteryx*, and *Sinornis*? Surely the first two are much more similar to each other ecologically than to *Sinornis*?

For instance, I do see a
problem with the term: "non-mammalian pelycosaur."

Happens to be hypothetical because people say "nonmammalian synapsid" instead. (Theropsida, actually erected as a clade name, would of course be better than Synapsida...)

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.

Firstly, ranks are allowed in PN. They just don't influence the spelling or synonymy/homonymy of names.

Secondly, ranks are not just merely useless. They are actively misleading. I'm sure you've seen many studies that count genera or families and pretend to have measured biodiversity, when in fact they've measured the opinion of one particular splitter or lumper and nothing else! Such studies have even been conducted by people who elsewhere emphasize that ranks have no real meaning.

Same goes for the old Linnaean rank system. It does
nothing to remove the validity of one group evolving
from another. It just places invisible boundary points
to allow for our brains (which seem to need to
categorize things) to better grasp the material. The
biggest thing the Linnaean system had going against it
(besides being founded during a time before the
acceptance of evolution) was that it didn't have
enough sub-divisions. The results of which have led to
messy things like infra-orders and the lot.

That's one biggie. Take the good old names Amniota, Tetrapoda, and Gnathostomata. (Amniota is Haeckel 1866, Tetrapoda is older than 1913*, Gnathostomata is venerable as well, so I'm not talking about some Ankylopollexia-Styracosterna every-node-must-be-named phenomenon.) All of these contain traditional classes and are part of a traditional subphylum (Vertebrata). They also contain each other. How many ranks are there between subphylum and class? Traditionally, there's just the superclass. Means, in a traditional classification you MUST CHOOSE: you have to pick one of those names (at most) and ignore the other two (or bump up Vertebrata to phylum rank, so you have to drop Chordata or Deuterostomia or something, or squeeze the traditional classes into subclasses, moving the problem elsewhere). Less traditionally, there's also the infraphylum. Makes two. Still you are not allowed to use all three in the same classification. Who needs this? Does this any good? Actually, it's nothing but chutzpa.

* You will sometimes see it attributed to "Goodrich 1930". That's plain wrong. Goodrich 1930 merely uses the name, like Broili 1913 and several works in between, without implying that it were in any way new.

One might argue (as HP Williams pointed out for
planets) that life is a continuum with all points of
separation being arbitrary in nature.

Ah, no, we're not back to the days of Lamarck and Jussieu. Life is not a continuum (points on a one-dimensional line), it is a tree; almost all imaginable lines between any two organisms cross a very real gap.

Further, there are many non-cladist scientists (who
still use cladistics) out there. Most notably on this
list (and I'm going to sound eerily like Ken Kinman
here) would probably be Michael Benton.

Benton has published several cladograms. What you're talking about is that he doesn't use PN. (Judging from his 2000 "critique" of it he simply doesn't understand it.)

Even
cladistically minded herpetologists like Eric Pianka
and Laurie Vitt, still use classic ranks for
classification (families, subfamilies and the like).

Do they stop above the family or superfamily, like Frost et al. do in their recent humongous phylogeny and classification of extant amphibians? If so, an important reason could be the desire to have nomenclature regulated -- and the PhyloCode isn't implemented yet, so there is no other choice than the ICZN, which stops above the superfamily.