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RE: Science feather strength debate
Greg Paul wrote:
<The claim that I have not properly documented my mass estimates is offensive
and ignorant. The basic technique is widely used, I been have presenting the
methods for restoring body masses for decades, and I go further than most
others in presenting multiple view restorations of many species.>
Ok, I am going to call you on this. Not only is this statement in rank
ignorance of the debate in which your method was questioned, the entire
statement ignores the premise that this is about science and not art. They are
not the same thing, although they may overlap.
Your method, as detailed in _Dinosaurs of the World_, is not detailed. It says
you make physical models based on your reconstructions, and use the volumetric
displacement method to calculate the mass of the model, then expand that at
scale. This does not tell us the value of the reconstructions used for the
basis of said model, or the detailed speculation made on how stance and
muscle-mass volume affects these models. Instead, it is performed as I said:
You make a reconstruction, applying a variety of assumptions (some of which
have been questioned) in restoring the anatomy of a skeleton (including missing
parts, length estimates, etc.), then use this to apply a assumption of muscle
structure, none of which is based on primary data on mapping muscle locations.
If anything, the muscle system and gut volume, ligament position, the "thick
neck" of hadrosaurs, the "nuchals" of sauropods, are all hypothetical, but
apparently assumed. I don't know, _you do not detail this in your
reconstructions of the body masses_. It should be apparent that missing
information on your reconstruction method makes the method patently unusable as
a scientific measuring stick for others' works. Claiming then that your work is
derided or ignored is fine, but it is done because the methodology is opaque
inherently; claiming that the methodology as explained is sufficient is
Your reconstructions (for which you base your models on, apparently, and only
that) are based on artistic license and speculation. To claim that the art
involved is anything but a suggestion, an idea, of how this skeleton might be
arranged, is to ignore the very purpose of the art in the first place. Instead,
you claim the art is science, and as I said, it overlaps, but not even 50%.
Scientifically, you'd have to admit that your work is speculative and an
hypothesis to be science, but instead you claim the overlap is actually 100%.
From this, you have claimed that derivatives of the art are "correct" or
"accurate," as if there is a 1:1 correspondence involved. This is not even
hyperbole, but grossly misrepresentative of the purpose of your art in the
first place: to merely demonstrate an idea.
If you believe you are correct, this is fine, you can say so. But always
preface this with such a statement of projected belief, rather than argue that
others hsould believe it, too. Otherwise, you're practicing religion.
Jaime A. Headden
The Bite Stuff (site v2)
"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
> Date: Sat, 30 Oct 2010 17:34:06 -0400
> From: GSP1954@aol.com
> To: email@example.com
> Subject: Re: Science feather strength debate
> For Jason to say that Nudds and Dyke set a high standard for scientific
> methods when every single mass and feather shaft diameter measurement they
> presented in a leading science journal was way off the mark, and they
> grossly inadequate documentation and other errors is an outrage. What are
> you thinking saying such a thing? Also an outrage is implying that my reply
> was scientifically inferior to their error riven paper when mine produced
> accurate measurements with documentation. The N&D paper is so flawed that it
> should be withdrawn. I have since learned that they have been developing a bad
> reputation in the field, it is they who need to reform. Really badly.
> The most important reason that N&D made (yet another) major mistake in not
> citing DA is because had they done so they would have been forced to use a
> more correct body mass for the Munich Archaeopteryx they examined, rather
> than being dumb enough to use the much higher Berlin specimen mass. There is
> not a dispute concerning the mass of Archaeopteryx among those who have
> restored the species volume since three researchers have arrived at
> the same mass for the Berlin speciems.
> The claim that I have not properly documented my mass estimates is
> offensive and ignorant. The basic technique is widely used, I been have
> the methods for restoring body masses for decades, and I go further than most
> others in presenting multiple view restorations of many species. The
> specific gravities are listed -- not that it makes all that much difference
> because even animals "riven" with air sacs do not have SGs all that far below
> land animals without them (because most animals have large lungs, their
> internal air volume is not dramatically lower than birds in which the lungs
> much smaller - i. e. to a degree birds trade large air sac volume for
> smaller lungs -- the resulting difference in mass is only about 10-20%, not
> enough to seriously alter calculations of flight feather strength).
> The mass of the pigeon cited in the reply is that of a live animal of the
> size figured, so there is no need to estimate its air sac volume.
> My skeletal restoration volumetric Munich specimen mass was published as
> the Science reply clearly cites years ago in DA. It is not based as Jason
> seems to imagine on some comparison with pigeons (the figure in my reply is
> intended to visually show readers of Science that the Munich specimen is much
> smaller than a pigeon).
> In his fantasy world Jason imagines that for some reason I must and can
> reply to N&Ds hyperdefective paper only by "recruiting "a team of eager young
> biologists and engineers to build aerodynamic models" to test their methods.
> Jason who works at a large budget museum is detached from reality for those
> who do not have access to such resources. How the hell I am, an independent
> researcher with no budget (it's not like I can get a grant from the NSF --
> or David Koch) I can supposed to do that? Here, Jason, is how it works in the
> real world I live in. I come across a paper that (as the reviewers of my
> reply noted should not have gotten past peer review) has one glaring defect
> after another. It is begging for a rebuttal, and it was well within my
> capacity time, budget and skill capacity to write up and publish the badly
> reply that points out the obvious defects so the scientific community can
> take them into account. That is all I need to do -- it's standard scientific
> procedure to produce short rebuttals limited to specific errors (that's what
> Technical Comments is for), Jason seems to think that a rebuttal must be a
> large comprehensive study. Others are now free if they wish to try and further
> develop methods for examining wing feather strength with they resources
> they have available (but not for Archaeopteryx because the needed data is not
> present in the fossils), and with my data promplty published in the
> literature available for further work. That too is how science works.
> In a message dated 10/27/10 11:50:35 AM, firstname.lastname@example.org writes:
> << In your recent posts about the Nudds and Dyke Paper you have called
> their conclusions silly. I wholeheartedly agree with you that they should have
> presented good figures for proximal rachises along with their conclusions
> and that this missing data weakens the paper. But on other points I fear you
> have seemed dismissive.
> Correct or not, Nudds and Dyke have provided an explicit and empirical
> methodology and their conclusions can be supported or falsified on their own
> terms. In accomplishing this they have set a high standard for scientific
> I would suggest that their method calls for a response in kind, and that
> you should recruit a team of eager young biologists and engineers to build
> aerodynamic models to test, for example, whether the overlapping feather vanes
> of Confuciusornis would strengthen the wing enough to prevent buckling.
> You are free to analyze whether the proportionately long arms and short
> legs of Confuciusornis correlate in a statistically significant way with
> animals and do not overlap with non - flying animals.
> You are also free to analyze whether there is a statistically significant
> correlation between flight abilities and the formation of abundant
> lacustrine fossils.
> All of these are scientifically valid responses, but I don't feel that
> categorical dismissals are.
> You wrote that you were irritated that Nudds and Dyke (and "lots of folks")
> did not cite Dinosaurs of the Air. Speaking for myself, I feel that your
> book could have been far more persuasive and influential if its methods had
> been explicit and if it had proposed methods by which your hypotheses could be
> For example, I could not find the calculations that you used to estimate
> body mass for Archaeopteryx in either DA or Predatory Dinosaurs of the World.
> In the former you do mention Yalden's calculations, but then you state that
> his estimate is too high and you lower it without providing any mathematical
> reason for doing so. In your technical comment on Nudds and Dyke you show
> two elevation drawings: silhouettes of a pigeon and of Confuciusornis, as
> your only evidence that the pigeon weighs more. But a pigeon is a three -
> dimensional object, and riven with pneumatic air sacs. If the pigeon was more
> voluminous you did not calculate this, and you provide no evidence as to
> whether the pigeon is more or less dense than a more basal bird. Then you go
> on to
> say that the lower mass of the Munich Archaeopteryx makes the feathers
> "several times stronger" when you must have meant that they have several times
> less loading. But my point is that you are less persuasive when you simply
> write that this is so than you would be if you provided calculations that can
> be checked by your readers.
> If we hypothesize that Confuciusornis was capable of powered flight, this
> hypothesis must be falsifiable in order to be scientifically valid, correct?
> So perhaps one day an overwhelming body of evidence will demonstrates that
> it was a littoral scavenger that roosted in trees overhanging lakes, and
> parachuted down to the shoreline to forage. You and I think that this is
> unlikely, but that doesn't matter. What matters is that we design
> experiments rigorously so that their results will be believable. >>