[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

was: Avgodectes, now: eyeballing



Either one supports cladistic analysis, or one supports 'eyeballing'

DMarjanovic wrote:
Firstly, there's no point in including both juveniles and adults of
potentially the same species in an analysis, because they will likely
not show up as sistergroups due to the fact that many apomorphies appear
only at some time between hatching and maturity;


>>>>>> On the webpage: www.pterosaurinfo.com/pterodac_clade.html  you
can see that No. 9 and AMNH 1942 have identical torso sizes. Are they
the same ontogenetic age? AMNH 1942 has a much longer neck and rostrum.
Is it an adult? If so, how can this be? It's tiny, except for its neck
and snout. Similarly on the webpage:
www.pterosaurinfo.com/scapho_clade.html  you'll note that tiny No. 9
(the 'model' baby pterosaur) follows Scaphognathus cladistically and
overall resembles one more than it's presumed parent among
pterodactylids. Okay, the tail has diminished and the metarcarpus has
lengthened  ? but these are only two characters ? and this is what they
call "evolution". Again, note that its cladistic successor, No. 12, has
an identical torso size. Only the legs, neck and rostrum have increased.
Does that mean in pterosaurs that the torso does not increase from
neonate to adult? Cladistic analysis takes into account everything from
palate element ratios to phalangeal proprortions.

DM:
secondly it's potentially misleading to include species known only from
juveniles because they will likely appear in a too basal position, for
the same reason as above. In
short, do include all tiny pterosaurs in your matrix -- after you've
shown that they are really adult.

>>>>>>Statement falsified by the placement of baby Pterodaustro next to
adult Pterodaustro.


DP:
         Others need me to
         visit every taxon (this is common practice in matrices of 7 to
25
         suprageneric taxa, hasn't been done in matrices over that)

DM:
Of course it has been done. I happen to know the example of HP Oliver
Rauhut's really big* theropod matrix in his dissertation.


>>>>>>>  You need to stick with the subject. The subject is Diapsids.


DP:
         It's funny, how at one time everyone was shaking their finger
saying
         'without a cladogram there is no evidence' but when a cladogram
is
         supplied that reflects past work ? and only departs dogma with
the
         addition of taxa (see Müller 2004 to see how important taxon
         selection/addition is) then feathers start to fly.

DM:
Adding taxa can be botched up.

>>>>>>>>
This is for the referees or the next generation of grad students to
_show_ that the additional taxa are botched up. To assume or presume
that there is a botch up shows prejudice, not science. To blindly
accept, on the other hand shows faith. Everything should be tested.
Mistakes need to be noted.


DM:
See above for the need to be careful with assessing maturity; see my
misery for the great benefits of personally examining fossils that are
poorly described and illustrated, not to mention the fact (mentioned
several times on this list, years ago) that published data matrices
often contain typos and must therefore not be simply copied; see
theoretical studies and my experience for the need to add characters
when you add taxa (...and
even when you don't add taxa).

>>>>>>>>
I note that others have copied data matrices, character lists, etc. in
prior work, so your finger pointing should be at them. That hasn't been
done here. Again, to presume otherwise shows prejudice.


DP:

         3. Evidence of what basal plantigrade pteros did with that dang
big
         lateral toe while walking (see keyword: 'sauria aberrante' for
the alt.
         explanation).

DM:

It looks (er... literally) like it was involved in the "hindwing". But I
wouldn't bet money on that.

>>>>>>> Keyword: walking. And no one, even Unwin and Bakhurina 1994, has
shown in detail (not cartoon) that the toe was involved with the hind
wing, or rather the uropatagium

DP:

         4. Evidence that pterosaurs were related to dinosaurs, or any
archosaur.

DM:
Several published cladistic analyses, plus reportedly a big unpublished
diapsid analysis (lots of taxa, including "prolacertiforms") by Senter.

>>>>>> Pterosaurs were not taxa in Senter's analysis. Otherwise, in the
several published cladistic analyses you refer to (all small, by the
way) lizards were not included so pterosaurs nested with dinos by
default.


DM:
Sorry for the impolite question, I'm too tired to think in terms of
social intelligence -- have you found out how to order multistate
characters in a NEXUS file?

>>>>> Of course, but that needs to be done with assumptions. I prefer to
work without assumptions.

DM:
When I saw your pterosaur matrix -- long ago! -- you had several
characters that were morphological series, yet all your 183 or so
characters were unordered
and thus _had to_ produce _bogus_ results.

>>>>>>> why bogus? Name three characters that benefit from ordering.

DM:
Iinterpretation of the fossil doesn't look convincing...


>>>>>>
Again: Either one supports cladistic analysis, or one supports
'eyeballing'