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Fwd: Science feather strength debate
> Dear Mr. Paul,
>
> Please accept my apologies for outraging you. I offered my comments in a
> collegial spirit, as an ally in our common pursuit of understanding the
> evolution of avian flight. My suggestions are a sincere attempt to be
> helpful. No one can deny that your work has been groundbreaking and even
> prescient.
> In your postings you described a sense of frustration that Dinosaurs of the
> Air was not being cited by other authors. Perhaps I have been too blunt, but
> I am trying to convey to you the sense that I get from others in our field,
> and to suggest how your work can possibly be elaborated in order to find
> wider influence.
> On Oct 30, 2010, at 5:34 PM, GSP1954@aol.com wrote:
>
>> 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
>> presented
>> grossly inadequate documentation and other errors is an outrage. What are
>> you thinking saying such a thing?
>
> I must have been thinking the same thing that Zheng et al. were. As they
> wrote, though the measurements may have been confused by preservation issues,
> the method developed by Nudds and Dyke could be useful in the future. Zheng
> et al. plugged their own measurements into the formula and found that the
> feathers were stronger, but still far weaker than any extant bird relative to
> mass.
>
>> 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 should be withdrawn.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.
>
> This is perhaps the crux of our disagreement. I see a distinction between
> methods and results: between simply being right and being able to prove that
> one is right. To my mind it is most important for workers to present their
> methods explicitly enough that others can duplicate their experiments. After
> reading your two books I still wouldn't know how to duplicate your method for
> finding body mass. Your prodigious expertise and insight may well have
> brought you to the correct answer, but this is less scientific than if you
> had developed an empirical method that others can use.
>
>>
>> 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
>> approximately
>> the same mass for the Berlin speciems.
>
> I don't think it is appropriate to call the authors dumb for disagreeing with
> you.
>
>>
>> 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. 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 most
>> land animals without them (because most animals have large lungs, their
>> internal air volume is not dramatically lower than birds in which the lungs
>> are
>> 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).
>
> a 20% difference in mass makes a big difference in aerodynamics and
> especially the metabolic costs of flight. Moreover, if the anterior body is
> more pneumatized than the hind parts this has implications for flight
> configurations. And, again, the mass does not affect the feather strength,
> which is inherent to the feather structure. The mass affects the loading on
> the feathers.
>
>>
>> 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
>> needed
>> 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.
>
> I think you sell yourself short here. Your reputation is eminent and your
> work is inspiring to anyone with so much as a passing interest in the
> evolution of birds. I can imagine that dozens of students and researchers
> around the world would jump at the chance to volunteer some computer or
> mechanical modeling work, or statistical anlaysis, on a project with Gregory
> S. Paul. I can imagine students who would be delighted to do their thesis
> projects on something like this and professors who would be delighted to host
> you in their labs to study these questions.
>
> I am fully aware that a letter to a journal is a short form. But, again, in
> the same form Zheng et al. looked at Nudds and Dyke, re-ran the experiment
> with their own measurements, and found that Nudds and Dyke had made errors
> that exaggerated the degree of weakness, but that their conclusions that
> these two extinct animals had feathers weaker than extant birds were
> fundamentally correct.
>
> I would close by humbly asking you to consider ways that your methods can be
> made to look more like experiments and less like declarations. You're
> probably right. The tricky part is proving it.
> -Jason
>>
>> GSPaul