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| (The elusive Higgs Bird, from Chester Reed | via Wikimedia Commons) |
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Happy Holiday! to my US readers… and Happy Higgs Day! to my European readers (and science buffs EVERYwhere!)… now that 'The God Particle' is being confirmed, perhaps the Lord God Bird will follow… ;-)
anyway, just one actual IBWO note of curiosity today:
I recently clicked to Louis Bevier's honed (skeptical) site on the Ivory-bill debate, only to find it gone:
http://web.mac.com/lrbevier/ivorybilled/Overview.html
Having not visited for several months, not sure when it went down, but apparently Apple dropped that particular domain from use at some point. So I surmise that either…
1) Louis, purposely or accidentally, let the site disappear, since he has the hard data and may feel the debate is long-settled, so no need to continue the Website... (or he may be re-working the material to re-post the site).
2) or, if by chance he is planning to publish further, extended material on the matter (in an academic journal), he may have felt no need to keep the Website up-and-running with a more formal publication in the offing.
3) or, he may simply be tired of being associated with the entire IBWO topic at all and moved on.
There are other possible explanations as well I s'pose, so if anyone knows more, or if his site can be found at some new URL, please let us know.
You can, by the way, still find most of the text portions of Bevier's old site via the Internet's Wayback Machine here:
http://tinyurl.com/6omqdkf
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4 comments:
Ct is quite generous with the possible reasons that site is gone. Recently D. Sibley visited this blog and referenced that site.
He was met with specific criticism on various subjects and on wing beat frequency of the AR video in context of the Imperial Woodpecker video. My criticism of the skeptics’ version of the heuristic IBWO wing beat Hz predated the IMWO video by several years but certainly the very late converts to the correct analysis of this important characteristic of Campephilus spp are welcome.
Perhaps Sibley who seemed to be intimately involved with the Bevier material (same exact format design as Sibley’s Blog) finally saw the obvious errors and over reach.
As we all know now, including entrenched skeptics, there are no PIWO videos that show a > 8 flap Hz post 4 secs from takeoff in level flight. That’s because its impossible for them to do so for several synergistic reasons.
Any serious analysis of flap Hz of the existing poor quality putative IBWO videos would certainly rule out PIWO leaving the null IBWO).
Here is something perhaps posted over 4 years ago on Bird forum or Frontiers.
Hypothetical Wing Beat Frequency of IBWO
Although there is a general inverse correlation between body mass and wing beat frequency in Picidae/other avitaxa plotted data points of individual spp. measurement variables are non-linear with many outliers that seem to be deviations away from the slope line.
In fact there are numerous congenerics that do not come anywhere near the slope line extended by Louis to link his “heuristic” plot point for the IBWO.
One would expect that congenerics with similar morphology only differing in scaling would show the resultant drop in wing Hz as mass increases but even this is often not true in even a small sampling of NA Picidae taxa. This shows that mass is not the main variable to be isolating and it warns prudent researchers to not compound errors by then taking the further leap of comparing birds of distant relationship and drastically different morphometrics using mass alone. IBWO and PIWO are from different genera and have quite different wing shapes.
Look at the subject graph on the bottom link (p 19 graph B) and you will see that the Hairy and Downy with very similar relative dimensions have a very similar wing beat frequency even though all pertinent variables increase proportionally.
The graph shows when we freeze all variable deltas the wing beat frequency remains ~ the same. Therefore some NA Picidae, EVEN WITH A 160% INCREASE IN WEIGHT (DOWO/HAWO) do not approach the slope line used by some to publicly conjecture on the IBWO Hz.
Louis said >>>>>> The graph on my web site is simply a replotting of Tobalske's data with the addition of bars that show the wide range of variation seen in even a small sample size<<<<< and
>>>>>> I also added points for Ivory-billed using Tobalske's regression equation derived from the data in the graph. This demonstrates what is an expected rate for level flight, nothing more. <<<<<
cont.
The author, Tobalske did not add in the IBWO points and the extension of the slope line are solely Louis’ doing.
It’s improbable that an author seeking peer approval would base the hypothetical wing Hz frequency of any bird, let alone this high profile species, based on one variable such as mass and ignore the others. Especially when the other variables have a summated majority weighing that determines wing Hz.
Louis has emailed me privately that the IBWO plotted point is caveated yet his introduction verbiage is quite authoritative and non-heuristic.
He seems to be inferring he has created the definitive pronouncements and work on the subject, e.g. case closed:
>>>>>. I hope the data and analyses presented here will put this issue to rest. The bird in the Luneau video flaps at a rate consistent with Pileated Woodpecker. <<<<<
Louis on Forum said >>>>>Tanner and others frequently refer to the species' fast flight, but not to fast wing beats. Many people conflate these two things; yet speed and flapping rate need not be correlated.<<<<<< .
To disabuse the few readers that swallowed that one …wing flap Hz is highly correlated with level flight speed throughout our avidiversity. We are not talking about Peregrines in dives or Falconiformes in thermals.
I will dignify this with only a few references/words of the hundreds available. Jackson devotes pages in his recent book to the flight pattern and prefers Tanner, who likened it to the flight of a Pintail, "with steady rapid wingbeats."
Compare this to the PIWO’s level flight which is described as crow-like with wing tucks. Jackson the authority accepts the best field authority……and concludes “rapid wingbeats”.
And finally look at pg 17 of 27, graph A below, Picidae wing area vs. mass. This shows that the IBWO is a potentially special NA taxon in regards to Hz since if plotted it does not fit the slope line while other NA Picidae do follow the slope very closely.
This is the pertinent base graph which leads to the strong inference that IBWO must compensate a high wing loading with increased wing Hz.
http://elibrary.unm.edu/sora/Auk/v113n01/p0151-p0177.pdf
The Auk 113(1):151-177, 1996 Tobalske
Good calculating,
Fred Virrazzi
Don't know if I was "generous" or not in ascribing possible reasons for the loss of Bevier's site, and am honestly surprised no one has emailed me (or commented) with a definite answer... I'm sure some reader out there knows what the actual case is.
One emailer did ask why I haven't simply emailed Bevier myself, so for others who may have the same question I'll repeat: last time I communicated with Louis it essentially ended with him requesting NOT to be contacted any further about IBWO matters, and I said I would respect that wish... he seemed quite frustrated, even aggravated, that the debate was still carrying on in some quarters (I'll add, so as not to imply otherwise, he was always polite and cordial throughout our communications).
I assume that Lammertink et.al. are still planning to publish some sort of formal analysis/commentary on the Imperial footage (...although always iffy to presume anything on the part of the Lab of Ornith.!) and it would be interesting to know if Bevier has had input in that regard (I'm doubtful he would be a co-author, though he has co-authored with Lammertink and other Cornell-ites previously, and they might well have asked for his thoughts/critique).
Time will tell....
CT you were generous since you did not include the most likely reason, to an important educated segment of viewers, on why the pseudoskeptic site is not worth renewing. It would have only cost a few dollars to renew, so its not cost. This is the greatest mystery in conservation in decades. Shouldn't accurate sites be renewed and flawed, science or sites whither away?
That site, the Science Note and subsequent apprearances by "Note" authors Bevier and Sibley failed to convince any of the ~ 16 Science authors, none of the many public posters with a real name, none of the proponent AR RBC members and most importantly, no one of substance at the USFWS that the orignal abstract was wrong------the abstract stands --the IBWO Persists (2004). The USFWS determines what is or isn't an extant endangered species------not silly sites by amateurs that practice flawed freshman logic. Or blogs that want a specific thread to go on forever by picking up a defeated tag team of combatants from the bloody canvas. Sure you can say it was good battle for 7 years but its fairly clear that the words "IBWO Persists" were right for the AR video and by proxy the LA video.
The site was not renwed becuause it was ineffective bullocks.
Those that have learned about REAL video artifacts, GISS, subtle to obvious clues to correct bird ID, bird wing flap frequency, aspect ratio, surface area, Campephilus characteristics, general aerodynamics etc., have concluded that site's major points were fatally flawed.
Have you seen or heard any great independant defense of that site's points from anyone? It's been critizised on multiple sites and forums. I am excluding from being great defenses, the ephemeral apprearances by the non-independant perpetrators of that site. .
They retreated and disappeared quickly as they withered from repectful, basic and fundamental questions about their erroneous opinions.
Why are you still willy nilly, and for years a trailing indicator at best, for the major tool of wing beat Hz in respect to the subject ID of birds on the subject videos? Hz and bounding do not vary by entire deviations.
tks
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