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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 should be withdrawn.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