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RE: 11th specimen of Archaeopteryx‏



  I do agree that when I said that the toes grade from two to four, then one, I 
was basing this on back of hand recollection, and am admitting my error. I was 
focusing, at the time, on terrestrial animals and basal paravians, where this 
is true at the base of extinct *Avialae*. Even *Cathayornis yandica* has a 
relatively short first ungual compared to at least unguals 2 and 3, even if 4 
is shorter (I think), and it appears even in *Protopteryx fengningensis*, both 
birds apparently highly arboreal. I admit I was fast and loose with some 
specifics, so I wasn't fully generalizing, and in this I admit my error.

  I didn't say anything about Fowler not being cited, although it should be 
noted that the work in question (Fowler, Freedman & Scannella, 2009) appears to 
focus on claw _curvature_ and _size_, but not other aspects of morphology. This 
may impair its relation to studies on morphology of either the bony claw to the 
sheath, or other functional implications of curvature. That is, the scope of 
the work is too narrow, even if the data set it draws upon (excluding oddities 
like swifts or palmate-footed birds) can be used in general.

 My cites and quoted comments were based solely on the topic of inference of 
arboreality from claw geometry (Yalden, Feduccia, et al.) or microstructure and 
FEA (Manning et al.), which is what this thread is somewhat about. I should 
note that moving ONE phalangeal position up from the ungual raises the issue of 
further argument about arboreality, something noted elsewhere (by Tim 
Williams), and this can also relate to the discussion than simple claw 
geometry. I want to make it perfectly clear that I don't think anyone has the 
right picture, because no one has made a complete assessment of the total data. 
That you _can_ get such a complete assessment is another question entirely, 
totally epistemological.

Cheers,

  Jaime A. Headden
  The Bite Stuff (site v2)
  http://qilong.wordpress.com/

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


"Ever since man first left his cave and met a stranger with a
different language and a new way of looking at things, the human race
has had a dream: to kill him, so we don't have to learn his language or
his new way of looking at things." --- Zapp Brannigan (Beast With a Billion 
Backs)


----------------------------------------
> Date: Tue, 8 Nov 2011 19:06:01 +0000
> From: df9465@yahoo.co.uk
> To: dinosaur@usc.edu
> Subject: Re: 11th specimen of Archaeopteryx‏
>
> Jaime,
>
>
> Myself and colleagues wrote one of the most recently published papers on claw 
> curvature in birds, its variation and functional morphology, considered with 
> the foot as a whole. We focused on birds of prey, but we have other 
> representative taxa, and the supp info has some data/discussion on these (and 
> I've looked at many more specimens since this was published). The paper was 
> published in 2009 in PloS (open access). Our measurements show that your 
> statements were completely backward. You stated that D-I is the smallest 
> claw: this is sometimes the case in cursors, but not in most birds, and 
> certainly not in perching birds. Your other statements were variably wrong 
> too.
>
>
> I'm not moaning about not being cited, because this isn't a journal, it's the 
> DML... but your general statements were backwards, and did not help the 
> discussion, their wrongness hinders it.
>
>
>
> ----------------------------------
> Denver Fowler
> df9465@yahoo.co.uk
> http://www.denverfowler.com
> -----------------------------------
>
>
> ----- Original Message -----
> From: Jaime Headden <qi_leong@hotmail.com>
> To: Denver Fowler <df9465@yahoo.co.uk>; Dinosaur Mailing List 
> <dinosaur@usc.edu>
> Cc:
> Sent: Tuesday, 8 November 2011, 11:45
> Subject: RE: 11th specimen of Archaeopteryx‏
>
>
>   But I was generalizing. I was doing so _because_ I was trying to discuss, 
> not end discussion; it doesn't help I don't have all references, but that is 
> why I am not actually just saying something is _so_, unlike Fowler.
>
>   The data is not simply assessing claw size/curvature variation, it is about 
> the specific of geometry and function, and how this interacts with behavior, 
> and how the latter cannot even be inferred for fossil taxa. It tells us 
> nothing about what we are meant to do with determining functional use in the 
> manual unguals of "raptorial" theropods (part of the point of Manning et al., 
> available here: http://onlinelibrary.wiley.com/doi/10.1002/ar.20986/full ). 
> My comments were generalizing because there are people making broad sweeping 
> statements without noting t
> ns in particular on my blog, to which you are referring, focus on my comments 
> about developing a taxonomic scheme after lumping specimen complexes into a 
> taxon. It is like telling me that a straight, broad tooth crown with no 
> serrations and fluting should belong to a spinosaurid theropod because ... 
> because! I mean, the functional relationships of the
> tooth are the same, regardless of whether the morphology can occur in crocs, 
> large fish, mosasauroids, etc. Microstructure analysis, isotope analysis, and 
> (dare I say, a hint of self-skepticism) prevents these teeth from simply 
> being lumped into a given taxonomic container, be it "family" or "genus" or 
> "whatever." The same is true of non-tooth specimens, or lumping complexes of 
> toe bones into functional arrays without assessing finer particulars (such as 
> their microstructure).
>
>   My argument has been, specifically, that the large ungual of the second 
> pedal digit is so very different from the other unguals that one cannot 
> simply make a bold statement in regards to the total behavior of the foot. 
> Sheesh, John Ostrom made this observation back in the 70s and 80s!
>
>   And I am not even getting into cross-sectional geometry, nor the 
> potentially highly distinct issue of reconstructing keratin sheaths over bony 
> unguals, and the relative problems involved when one is lacking.
>
> Cheers,
>
>   Jaime A. Headden
>   The Bite Stuff (site v2)
>   http://qilong.wordpress.com/
>
> "Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)
>
>
> "Ever since man first left his cave and met a stranger with a
> different language and a new way of looking at things, the human race
> has had a dream: to kill him, so we don't have to learn his language or
> his new way of looking at things." --- Zapp Brannigan (Beast With a Billion 
> Backs)
>
>
> ----------------------------------------
> > Date: Tue, 8 Nov 2011 18:12:53 +0000
> > From: df9465@yahoo.co.uk
> > To: dinosaur@usc.edu
> > Subject: Re: 11th specimen of Archaeopteryx‏
> >
> >
> >
> > I have followed this thread with interest, as I have papers on the subject 
> > published and pending (waiting on seeing the reviews for the MS based on my 
> > Bristol 2009 talk; so I won't elaborate here due to embargo etc).
> >
> > The generalized statements weren't even right generally. They aren't based 
> > on any published study, or even any casual observance of bird feet/claws, 
> > even a google image search can show that you are wrong.
> ibutions in birds is published in Fowler et al. (2009; and references 
> therein). Climbing birds (woodpeckers e.g.) have a zygodactyl foot, with 2 
> forward and 2 backward facing toes. One toe of each pair is typically large, 
> the other small, with the forward facing toes larger than the backward pair. 
> The foot has this symmetry related to how the woodpeckers move up and down 
> trunks, sometimes upside down (although usually the right way up, hence the 
> anterior facing toes are larger). Perching feet and climbing feet are very 
> different. perching feet (assuming they are adapted specifically for 
> perching) are anisodactyl (3:1) not zygodactyl (2:2). Claw size distribution 
> varies strongly depending on what feet are doing. D-I is usually largest in 
> non-cursors. Non-carnivorous birds usually have a D-III that is largest of 
> the forward facing toes, followed by D-II, then D-IV. Carnivorous birds have 
> a D-II that is as large, slightly
> > larger, or much larger than D-III; D-IV is smallest. Active predators 
> > usually have claws that are more curved than non-predaceous carnivores 
> > (although see fowler et al on owls). There are all sorts of exceptions etc, 
> > depending on specific behaviours. how this all ties into paravian evolution 
> > is the subject of our upcoming paper (PLoS One; reviews completed; 
> > literally waiting on response any day now).
> >
> > My point: there's often a lot of discussion and "facts" thrown about on 
> > this list. You always seem very quick to provide critiques of others work 
> > here and on your blog, without writing any papers of your own, or (as noted 
> > here) sometimes not having read the relevant literature on what you are 
> > discussing. This list isn't a peer-reviewed journal, I understand that, but 
> > it is a very public outlet for discussion of research, so when I see a 
> > string of "generalized statements" that are almost all very wrong,  I think 
> > there is a responsibility to point this out.
> >
> >
> >
> > ----------------------------------
> > Denver Fowler
> > df9465@yahoo.co.uk
> > http://www.denverfowler.com
> > ------------------------------
> ________________________
> > From: Jaime Headden <qi_leong@hotmail.com>
> > To: Denver Fowler <df9465@yahoo.co.uk>; Dinosaur Mailing List 
> > <dinosaur@usc.edu>
> > Sent: Tuesday, 8 November 2011, 10:17
> > Subject: RE: 11th specimen of Archaeopteryx‏
> >
> >
> >  I appreciate the absolutely informative and instructive email Denver 
> > Fowler replied with to my generalized statments regarding claw morphology 
> > and extant versus nonextant paravian theropods. The citations provided 
> > within by Fowler in refuting my statement, rather than labelling statements 
> > "you are wrong," while at the same time requiring me to provide statements 
> > to back up mine is the epitome of providing accurate and complete 
> > disclosure when making such generalized statements. I thank Fowler for his 
> > ultimately instructive reply to my email.
> >
> > Cheers,
> >
> >  Jaime A. Headden
> >  The Bite Stuff (site v2)
> > http://qilong.wordpress.com/
> >
> > "Innocent, unbiased observation is a myth." --- P.B. Medawa
> > ave and met a stranger with a
> > different language and a new way of looking at things, the human race
> > has had a dream: to kill him, so we don't have to learn his language or
> > his new way of looking at things." --- Zapp Brannigan (Beast With a Billion 
> > Backs)
> >
> >
> > ----------------------------------------
> > > Date: Mon, 7 Nov 2011 22:02:41 +0000
> > > From: df9465@yahoo.co.uk
> > > To: dinosaur@usc.edu
> > > Subject: Re: 11th specimen of Archaeopteryx‏
> > >
> > > _______________________________
> > > From: Jaime Headden <qi_leong@hotmail.com>
> > >
> > > > This is not entirely consistent with arboreality, although that is 
> > > > possible, because climbing birds do not use just one ungual for 
> > > > climbing...
> > >
> > > Yes, I agree.. oh hang on (!):
> > >
> > >
> > > >..., they use all forward-projecting unguals,
> > >
> > > Do they? Which climbing birds? What do climbing bird feet look like? Are 
> > > they different from perching bird feet? do you have a citation that 
> > > explains this? (hint, you are wrong).
> > >
> > >
> > > > In birds, while the unguals are graded largest to smallest moving from 
> > > > toe two through toe fo
> >
> > > Are they? which birds? do you have a citation that shows this? (hint, you 
> > > are wrong)
> > >
> > >
> > > >the unguals even in raptorial birds are relatively similar in size
> > >
> > >
> > > Are they? which raptors? do you have a citation which shows this? (hint: 
> > > you are wrong)
> > >
> > >
> > > >(cassowaries are freaks with straight pdII-3u's, ignore them)
> > >
> > > Correct. The only thing you got right so far.
> > >
> > >
> > > >; in dromaeosaurids, the pdII-3u is often twice the length of any other 
> > > >ungual, a suspiciously bizarre distinction that enforces a functional 
> > > >difference, especially in the strong curvature relative to the other 
> > > >unguals. And recall, despite the huge!
> > > pdII-3u, the other pedal unguals are _terrestrially_ adapted, even in 
> > > *Archaeopteryx lithographica*. Moreover, it is questionable how one 
> > > arrives at a conclusion that the highly recurved, huge forward ungual is 
> > > indicative of "perching" or arboreality to begin with, merely that 
> > > climbing is _not_ excluded.
> > >
> > >
> > >
> > > Paper is nearly here (hopefully b4 xmas). T
> > e to go back and read some papers on claw morphology. You need to.
> > >
> > >
> > > D.
> > >
> > > PS. I wrote Fowler et al. 2009. It has lots of claw data in it. Your 
> > > email didn't.
> > >
> > >
> > > ----------------------------------
> > > Denver Fowler
> > > df9465@yahoo.co.uk
> > > http://www.denverfowler.com
> > > -----------------------------------