Living the Scientific Life (Scientist, Interrupted)

Goodbye, Beautiful Dream

Extraordinary claims require extraordinary proof.

    — Carl Sagan

A trio of Ivory-billed Woodpeckers, Campephilus principalis.
Adult male (left) and female (lower right).
Painting by John James Audubon (1785-1851).

With every day that passes, the elusive ivory-billed woodpecker looks more like an apparition or, more likely, a case of mistaken identity. Bird artist and ID expert, David Sibley, and several of his colleagues, Louis Bevier, Michael Patten, and Chris Elphick, published a rebuttal that was released today at 2pm EST by the top-tier journal, Science (this rebuttal should be accessible by the public here or I can email the PDFs to you).

In his short paper, Sibley analyzes the Cornell team’s 4.5 seconds of blurry video, frame-by-frame, and concludes that the bird captured in the video is actually a case of mistaken identity; the bird is a pileated woodpecker (PIWO). This, based primarily on the black and white patterns on the bird’s wings, which he says differ significantly from an ivory-billed woodpecker.

An accompanying response, also published in Science, by John Fitzpatrick and his colleagues, Martjan Lammertink, David Luneau, Tim Gallagher and Kenneth Rosenberg, counter Sibley et al.‘s assertions by stating, among other things, that Sibley’s field guide depictions of the wing markings of the pileated woodpecker are incorrect. They also tried to prove that the wing patterns were still visible, despite the poor quality of the original video. To do this, they made cardboard models of both bird species and photographed them under similar circumstances to when the original video was made. They found that the trailing black edge of the wing in the pileated woodpecker was still distinguishable.

Basically, this debate has deteriorated into a battle over pixels.

I am disappointed, but not surprised, by this confusion over the bird’s identity. Considering the poor quality of the video, which is the strongest evidence arguing for the existence of the IBWO, I was surprised that the original paper was actually published by Science. But like almost everyone, I wanted to believe that somehow, this remarkable bird has escaped extinction. I want to believe that somewhere, this bird clings to life because by doing so, it redeems humanity, just a little bit.

But I want to believe that this bird lives only if it truly does. This bird’s existence becomes less credible, more tenuous, with every passing day. True, the surviving birds are probably terrified of humans, and yes, there are a very very few individuals out there to be seen, if they exist, but the fact remains that armies of highly trained and very experienced birders, hunters and fishermen have invested countless thousands of hours combing the region for this bird for two years. They have used every advantage available to them, every sort of cutting-edge recording device, from digital video cameras to sound recording equipment; they have set up remote cameras and tape recorders throughout the woods where this bird was seen and in other locations where the bird might still be found, yet nothing definitive has been recovered. This, after two years of diligent, dedicated looking.

Let me repeat; they have found nothing.

At this point, the search for the IBWO, which was almost prophetically nicknamed the “Lord God Bird”, is becoming something uncomfortably close to a religious pilgrimage. The intense arguments over fuzzy phantoms, double raps and “kent” calls, numerous ad hominum attacks between “the believers” and “the skeptics”, combined with an obvious evangelical fervor displayed by extremists on both sides, is depressing to watch. Daily, believers and skeptics alike congregate in a murky swamp to peer hopefully into leafy cathedrals towering over the Pearl River, blind to all its many wonders in their pursuit of That One Great Wonder that they seek, sometimes desperately. Lord God, where are you?

Is the bird there? Does the IBWO exist anywhere on this breathtaking, but incompletely seen and so poorly known world? It doesn’t appear likely. The bird’s silence is deafening.

I am not saying that we should give up seeking evidence for the continued existence of the IBWO. As much as anyone, I long for the return of that magical June morning last year when the IBWO flashed into glorious life from the shadows of extinction. I want very much to believe that this bird lives; that we are being given a second — completely undeserved — chance to right our wrongs by protecting this bird from our worst selves. But it appears that this will not come to pass. We, as a species, are not going to be emancipated by the IBWO. We were too efficient the first time.

But even in extinction, the IBWO continues to give generously to others. This bird has captured the imagination of the public like no other, thereby serving to sensitize us to the needs of creatures around us. The IBWO has motivated some of us to take action. As a result, previously unprotected regions of the Pearl River are now under the care of the Nature Conservancy and other organizations. Perhaps the best legacy that this ghost bird can provide is increased appreciation and protection for its former, mostly abused, home — something that should have occurred 100 years ago, when our intervention might actually have made a difference for this bird species.

But I refuse to believe in a ghost. I want tangible evidence: a decent photograph, a feather, an egg shell, or (dare I say it?) a body.

And to stir the pot a little, David Luneau writes cryptically on his website, “That black trailing half of the PIWO wing just won’t go away no matter how hard you hypothesize.”

Indeed. But my bird is not made of cardboard.

tags: , , , ,

Included with the best of bird-related blog writing by I and the Bird,
Issue 20.

The Tangled Bank

Included with the best science, nature and medical blog writing by Tangled Bank,
issue 50.

Listed as the Pick of the Week by the
Carnival of the Vanities,
issue 183.


  1. #1 P.M.Bryant
    March 16, 2006

    Has any evidence turned up in this winter’s search? I haven’t heard of any, but is it being kept under wraps?

    Certainly Fitzpatrick et al wouldn’t continue to defend their hypothesis so strongly if they didn’t have some further evidence from this year’s search?

    As I recall, there was a lot more evidence, even from just last year, than merely the video.

    A confusing situation.

  2. #2 Tara C. Smith
    March 16, 2006

    Does the pileated woodpecker’s call match that from the audio recordings?

  3. #3 Harlan
    March 16, 2006

    An old friend of mine, a physicist, once described of papers in Science and Nature, “suggestive evidence for things that would be really interesting, if they turned out to be true.” This seems to be in that category.

  4. #4 John
    March 16, 2006

    What I have heard about this year’s survey is that there have been some unconfirmed sightings. What this will mean in the long run, I don’t know. Given the charged atmosphere, it would help if Cornell were a little more forthcoming about what is going on. As it is, I don’t expect that we will hear much until the search year is over later in the spring. In the meantime, I think that we all would be best off taking a breather and waiting to see what happens rather than fighting over it.

  5. #5 GrrlScientist
    March 16, 2006

    PM; there is no new evidence that is worth noting. there are several new videos out there, but they are worse than the video that was used to confirm the IBWO’s existence, which is the same video that was analyzed by Sibley et al.

    why are Fitzpatrick at el., defending this ID? ego. and money. the money alone provides ten million reasons to defend the original identification.

    Tara; the bird in the video is silent, so there is no answer to that question. however, there are a few recordings from the Pearl River of “IBWO-like calls” but they do not match the audio analysis of the 1935 IBWO calls (i will be posting more about this after i finish Birds in the News, including those spectrograms). the best hypothesis is that blue jays were the source for those “IBWO-like calls” calls. blue jays, like all corvids, are gifted mimics, and they also can produce a wide variety of sounds of their own invention, apparently.

    Empidonax; have you noticed how the IBWO sightings are made by lone observers? in fact, almost all of the IBWO sightings, except for the first few, which are described by Gallagher in his book, were made by lone individuals. this makes it really difficult to have corroborating evidence, visual descriptions of the bird from different angles and whatnot.

  6. #6 Sara
    March 16, 2006

    So does this make you an ivory-billed woodpecker agnostic? 😉

    Maybe they’re hanging out with Elvis.

    But seriously, I’ve seen people defend crazier and/or less substantiated hypotheses for longer. Just look at cold fusion. So the growing emotional side to a supposedly scientific debate is, sadly, not too suprising. Ultimately though, there is no escaping the burden of proof, which is what makes science so great… and silence does indeed become deafening.

  7. #7 P.M.Bryant
    March 16, 2006

    Can you post a link to the Sibley paper? I’m having trouble finding it for some reason.

  8. #8 Patrick Coin
    March 16, 2006

    I share your sadness, but I reached the same point about six months ago. I was on cloud nine when the rediscovery was announced last year–I’ve wanted to see that bird my entire life (46 years, 42 as a birder). This sort of unsatisfying sighting without further verification by others or discovery of a breeding population has been going on since the 1960’s. Each time, I’ve had my hopes dashed.

    In the quote “That black trailing half of the PIWO wing just won’t go away no matter how hard you hypothesize”, Luneau is referring to the black trailing edge of the video of models made for their reconstruction. In the video of the models, the black edge of the Pileated Woodpecker wing is always visible, clearly different than the image of the model of the IBWO. The famous Luneau video of a flying woodpecker shows little, if any, black edge. (There might be a hint on a few frames, but that is debatable, and it is possible to confuse with image compression or CCD sensor artifact–see discussion here and here.) There’s a rub, of course. The reconstructions used static models, without the rapid wingbeats of a real flying bird, be it IBWO or PIWO. That motion, coupled with the relatively slow shutter speed of a consumer video camera, is one of the things that makes the pattern of the bird on the video so hard to interpret. The compression artifacts and “bleeding” of white areas are other issues, as is, I think, the angle of the bird in flight–hard to reconstruct exactly.

    So Luneau is defending the IBWO interpretation of the video with that comment, not saying it shows a PIWO.

  9. #9 emupilot
    March 16, 2006

    The video was the scientific evidence suitable for publication, but I tend to think the initial observations of Gene Sparling, Bobby Harrison, and Tim Gallagher are much more compelling. I don’t think it’s a conspiracy like cold fusion, as the fleeting sightings and audio evidence after the initial sightings make it seem especially unlikely that it was just a mirage. Hearing nothing since the rediscovery was announced is frustrating, and may lead us to believe the one found might have been the last one, but the Ivory-bill has led us down that road before. We need to have patience. If you want to be tantalized, however, there is a report here of a very reliable observer finding an Ivory-bill outside Arkansas.

  10. #10 Chardyspal
    March 16, 2006

    Living in the Pacific Northwest, I have seen quite a few Pileated Woodpeckers. I have seen how they fly and how they take off from the trunks of trees. I have seen how they look close and from afar. I have heard their calls. The bird in the video did not seem to me to be a Pileated Woodpecker. It seemed larger and the wings had a different quality when they moved. The call and rapping of the bird in the recording did not sound to me like a Pileated Woodpecker. I am no expert by any means, so my sad little observations are not worth much, but I will also continue to hope.

  11. #11 Home Bird
    March 16, 2006

    Grrlscientist, I have been following this story too, and I have a question I want to ask scientists. Your post is such a good example of a particular stance that so many scientists seem to take. I am not trying to be difficult or pick on you in particular, but your post provides me with the opportunity to ask this question. You write, “But I want to believe that this bird lives only if it truly does.” I have seen versions of this by several other people. Why is this desire more often articulated than its opposite: “I want to believe that this bird is extinct only if it truly is.” I see a greater fear–among scientists–in believing in the existence of something that doesn’t exist than in the nonexistence of something that does exist. If you follow. Do you have any insight into this phenomenon? I will be grateful for any response.

  12. #12 Sara
    March 16, 2006

    Dear Home Bird,

    If I may be so bold as to stick my 2 cents in. My feeling is that you are, without realizing it, skewing the interpretation.

    First of all, in this particular case, right now the evidence is heavily in favor of it being extinct. Nobody has even seen one in a very long time. So for the opposite to be true, requires solid, verifiable proof. It’s not being ‘negative’ to not want to believe arbitrarily in a bird that has still not been shown in any conclusive way to exist.

    Basically, the default position is generally (and supposed to be) on the side of the current evidence. When I am working with other scientists on a project, I don’t come across any bias like you are suggesting.

    But where science tends to intersect with non-science, is in the realm of certain typical arguments, often to do with something supposedly existing but with no proof. The Loch Ness monster, Sasquatch, ghosts, demons. Religion, angels, God. Elvis. Psychic powers. Magical healing cures. Magic in general. You get the picture. And in those arguments science, and scientists, are almost always forced to take the ‘non-existence’ side like you are noticing. But it’s not because we tend towards nihilism, it’s because currently there is no scientific proof for the above. So despite what a person wants to think or feel about it, the scientific evidence is all on the side of those things either not existing, or the situation being inconclusive (e.g. God for some people).

    Some examples of reversal of this: Scientists currently believe evolution exists, and global warming exists, but a large part of society for various reasons is insisting it doesn’t. So in this case, it’s the non-scientists insisting something doesn’t exist. The problem is, in these cases, the burden of evidence falls on the side of these things existing.

    This is why I think there is a bias in your perception, because science falls on the side of evidence, not of ‘proving that something exists’. You are thinking of this in terms of a narrow subset and not about science as a whole.

    Just my thoughts.

  13. #13 Home Bird
    March 17, 2006

    Sara: Thank you for your response. I understand what you are saying but am not convinced. Your counter examples of evolution and global warming refer to processes, not organisms, and both have complex histories in terms of how they have been presented to science and to the public. Evolution was rejected by mainsteam science when it was proposed, and I believe that “science” has done a poor job in explaining it adequately to the non-scientific public. (You may disagree.) And the issue of global warming has been highly politicized, with “scientists” being paid by oil companies and others to present distorted and inaccurate evidence against the process in order to further their own agenda.

    I do think you have hit the nail on the head, however, when you mention, “The Loch Ness monster, Sasquatch, ghosts, demons. Religion, angels, God. Elvis. Psychic powers. Magical healing cures. Magic in general.” The preference for disbelieving in the existence of, for instance, the ivory bill, does seem to arise out of a concern for being considered unscientific, gullible or believing in magic. Which is why Jerome Jackson’s phrase, “faith based ornithology” cut so deeply.

    I do not necessarily believe that the ivory-bill still exists. I am willing to say that I do not know one way or the other. However, it is known that the bird did exist after it was presumed extinct. And that the presumption of its extinction has contributed to the loss of habitat–and still does. The argument can certainly be made–and should be, in my opinion–that the preservation of valuable habitat should not depend on the existence of a single species.

    My perceptions may be inaccurate, as you say. However, at this particular moment in the bizarre history of this species, it seems to me that scientists are becoming rapidly more and more alarmed by the possibility of being wrong on the side of believing in a “mythical being” than by the possibility of being wrong on the side of believing in the extinction of the bird. In reality, of course, to be wrong in either direction is equally to be wrong. But one error seems to invoke a greater concern than the other. Again, I may be wrong, and hope I am (as so many have said about the ivory bill lately). And thank you again for your response and thanks also to Grrlscientist for providing the space for this discusion.

  14. #14 Sara
    March 17, 2006

    Dear Home Bird,

    You won’t hear me arguing about how science and scientists are not good at explaining things to the general public. But you also need to recall that’s a two way street. How much science is being taught? How many people are interested in science and willing to have the patience to meet it halfway? The situation in the US is reaching a crisis with this. And, for example, recently a friend asked a question about using a microwave, and I told him I could easily explain the principle so that he would understand why. He rolled his eyes and said that he frankly just wasn’t interested and didn’t want to hear about it. I hear that type of attitude a lot from non-scientists, which totally baffles me. And the local paper insists on publishing uninformative speculations by laypeople and refuses to publish or even solicit opinions from scientists, even when they are freely given. The situation is a lot more complicated than you might think.

    I still don’t see where scientists are being nihilists by not wanting to ‘believe’ in something unsubstantiated. Why? Because there is no scientific evidence. If I reproducibly produced a ghost that someone could test, you can believe that science would suddenly accept ghosts.

    Regarding the comments on evolution, it was controversial from the beginning but because of the societal aspect, and not so much among scientists. Basically a similar debate to today in the US. You make the distinction between ‘objects’ and ‘processes’ but I chose only two relevant, current examples, which just happen to be processes. Science stands on the basis of evidence. I could believe that a certain molecule exists as a product in a reaction, but I would eventually have to prove it. Or for example, scientists believed HIV existed and caused AIDS but they still had to prove that too (and did). As I said, I just don’t see the distinction you are making in the real world of science.

    Back to the original example: many scientists feel that there is strong evidence for this bird being extinct. As Grrlscientist said, everyone would love if that were NOT the case. And, maybe that bird is out there, even if nobody sees it and it becomes like Elvis sightings. But in order for science to say that this bird is conclusively back, there needs to be proof. Yes, it used to exist. Then it disappeared. We’ve killed off a lot of species that we ‘stopped seeing’ and we never saw them again. So that alone is not enough of a supporting argument… and I think Grrlscientist is being rightfully skeptical here.

  15. #15 GrrlScientist
    March 17, 2006

    Sara; you could say that, yes. by the way, did you know that huxley (“darwin’s bulldog”) invented that word, “agnostic”?

    PM; see your email.

    Patrick; thanks for making that clearer. that’s what i get for trying to write at three in the morning. i edited that to make it clearer for my readers, too.

    emupilot; oh, i don’t think it’s a conspiracy, as some of my colleagues do, but i do think that the evidence doesn’t support such a vigorous defense.

    Chardyspal; hope is the thing with feathers that perches in the soul.

    HomeBird; i prefer to believe in that which can be proven because it allows me to sail around the world without worrying that i will fall off the edge, it allows me the privacy of my own thoughts without worrying that i will be struck dead by a lightning bolt from the heavens.

  16. #16 Home Bird
    March 17, 2006

    Sara and GrrlScientist: thank you both for your responses. I have clearly not articulated my question correctly, and apologize for having apeared to suggest things I did not mean to suggest. I certainly never meant to suggest that scientists were nihilists, nor would I expect anyone to believe in the unprovable. I think the confusion arises because I evaluate the evidence in this particular case differently than you do, and perhaps I would have a different opinion if my training in evaluating, for instance, video evidence were better. I do not find the evidence for extinction so much more compelling than the evidence for existence, but that may very well be due to my own scientific ignorance. To be entirely specific, David Sibley’s explanation and conjectures about the posture of the bird, the wing patterns, and other physical details in the video seem to me to require as much of a leap of faith as the Cornell/Luneau explanation, if not more. I have read his article and supporting online materials, and looked at the pictures several times as carefully as possible, and I still do not see what he says is there. This may be the result of my own ignorance.

    However, what I was asking was why, when the evidence does not seem particularly stronger on one side than on the other, does there seem to be a bias for preferring one side. But I may be wrong about the existence of such a bias. If so, my apologies. I also apologize if I appeared to be suggesting anything more–or less–than that; and again, thanks for the courtesy of your replies.

  17. #17 Sara
    March 17, 2006

    I’m sorry if I’m still not sure what you are asking, maybe… although I think your last post clarifies part of it. I guess what I am trying to say on this is that your perception isn’t wrong, per se, but it is incorrect if you take it to the level of a generalization. I think insofar as you are talking about common discussions between the realm of science and the realm of general society, there is a type of discussion that tends to happen and that you are correctly noticing this. But what I am trying to say is that this isn’t what science is actually about, and that working in chemistry at least, I haven’t seen examples of the subtype we have been discussing.

    I have found that myself and many other scientists I know get into sometimes funny or strange debates with non-scientists, particularly because they often end with someone producing proof. Taking a discussion to this level among non-scientists is frequently viewed as, at best, weird and obsessive, and at worst, rude. I recall a non-scientist friend watching myself and another scientist debating the issue of food protection in the fridge for 30 min and I think they were a cross between horrified and amused. But there is definitely differences between scientist and non-scientist perceptions of the world, including the burden of proof, what is acceptable as proof, and when someone has won the argument. 😉 And among all true scientists, the facts are the fundamental determinant.

  18. #18 Sara
    March 17, 2006

    Grrlscientist, I totally did not know that, how interesting. (about origin of agnostic). I just looked it up on OED and it reads:

    “A. n. One who holds that the existence of anything beyond and behind material phenomena is unknown and (so far as can be judged) unknowable, and especially that a First Cause and an unseen world are subjects of which we know nothing.
    [Suggested by Prof. Huxley at a party held previous to the formation of the now defunct Metaphysical Society, at Mr. James Knowles’s house on Clapham Common, one evening in 1869, in my hearing. He took it from St. Paul’s mention of the altar to the Unknown God.R. H. HUTTON in letter 13 Mar. 1881.]”

    “1870 Spect. 29 Jan. 135 In theory he [Prof. Huxley] is a great and even severe Agnostic, who goes about exhorting all men to know how little they know. 1874 MIVART Ess. Relig. etc. 205 Our modern Sophists{em}the Agnostics,{em}those who deny we have any knowledge, save of phenomena. 1876 Spect. 11 June, Nicknames are given by opponents, but Agnostic was the name demanded by Professor Huxley for those who disclaimed atheism, and believed with him in an unknown and unknowable God; or in other words that the ultimate origin of all things must be some cause unknown and unknowable. 1880 BP. FRASER in Manch. Guardn. 25 Nov., The Agnostic neither denied nor affirmed God. He simply put Him on one side.”

  19. #19 GrrlScientist
    March 17, 2006

    it is true that one cannot prove nothing, cannot prove the lack of something’s existence. however, in this case, i think the IBWO is not there to be found because so much effort and energy has been expended by so many people for so many years, and no hard evidence has been put forward to reasonably argue that the bird lives.

    for an example, as a birder, i have chased after individual vagrant birds and actually found them, even though it wasn’t easy in some circumstances. and yet, even though i am a good birder, i am not a rabid birder as these boyz so clearly are. as a result, i think their inability to find the IBWO has nothing to do with them, their efforts or methods, i think it is because the IBWO is not there to be found.

    and on that day when they provide real evidence confirming that the bird lives, i will be cheering as loudly as anyone, perhaps louder, since, for me, the bird would have been raised from the dead a second time.

  20. #20 Home Bird
    March 17, 2006

    Thank you both again.

    Sara, I am not a scientist, but I am a former academic trained in analytical thinking and I completely appreciate many of your comments. I am often accused outright of being “over analytical” (which is not only insulting, it’s bad grammar) and know that many people consider me to be overly argumentative because I will not be persuaded without facts and “proof.” I hope your perception of chemists is accurate and am willing to accept your report, unless I find evidence to the contrary. In fact, I have a chemist brother and he fits your own observations. So, in this case, I will not (continue to) be overly argumentative and will let the issue drop.

    Grrlscientist: Your answer makes complete sense. You and I disagree about the weight of the evidence, but you have good reasons (more or less) for your opinion. The “more or less” comes from two issues: (1) my understanding that this statement by you is slightly inaccurate: “so much effort and energy has been expended by so many people for so many years.” From what I understand, and I really should do more research before I argue this point, there was actually shamefully little effort made to locate the bird until very recently. And perhaps that doesn’t matter if the recent search efforts have in fact been adequate. And secondly, I am also not convinced by Sibley’s article that the Luneau video does not show an ivory-bill.

    So perhaps I am wrong. The statement that I have not seen by scientists, and which led to my question, was this: “I do not want to believe that the bird is extinct unless it is true.” But perhaps those who might have made this statement have now been convinced that the burden of proof has been met.

    I was not trying to convince anyone of the existence of the IBWO, or to argue for “faith-based ornithology.” I was only trying to understand the lack of concern about being wrong on one side of the question when the evidence to me did not seem to be adequately compelling to have settled the issue.

    Let’s all hope that, if the bird does indeed live, those boyz come up with something fast–or we shall, as I have written before, lose the opportunity to save it before we even know it exists. In fact, it may be too late even now, even if a small population survives. The habitat destruction may already have reached the point of no return for the species. And that certainly seems to have resulted from someone’s (though not necessarily scientists) willingness to believe prematurely in the extinction of the bird, as Dr. Jackson argued years ago.

    Thank you for a good discussion.

  21. #21 Caio de Gaia
    March 18, 2006

    Home Bird, the problem is exactly how to define the “burden of proof” for something that may not exist. From someone in the outside it may seem like being negative, but in fact it is not. The most likely outcome of a field trip is not finding the bird. From a scientific point of view it makes more sense to assume as the null hypothesis that the most likely outcome represents reality, that is, the bird is extinct. Why?

    Because if you go in the field and your expected outcome is not finding the bird, and if that is what happens, you fulfill your expectations, that is you reinforce your belief in the null hypothesis. On the other hand if you find the bird (your least expected outcome), you get a nice publishable result in a top journal. And here is the important fact, finding the outcome opposite to your expectations solves the problem. What this means is that if the hypothesis is invalid and the bird is not extinct there is a finite chance of proving it invalid.

    On the other hand if you assume as null hypothesis “the bird is hiding somewhere and is almost impossible to see”, going into the field and not finding the bird (the most likely outcome) weakens your belief on the null hypothesis, but even if it happens 1,000 times it does not invalidate your claims. There can always be refugia somewhere. What this means is that this hypothesis can never be proven invalid, even if the bird is indeed extinct.

    The difference may be subtle but that is what distinguishes a scientific approach from a non-scientific one: there must be a way to prove your assumptions are invalid. An example is mechanics (in Physics). A rock thrown to the air on Earth always falls back, but what tells you that if you do it 1 trillion times it won’t keep going up? It might, but there is no point worrying about that until it happens.

    Does this mean that the people looking for these birds are doing bad science? No, and for several reasons. First because your resarch may be prompted by a possible sighting, and it’s you duty to check things that might invalidate your null hypothesis. Second because you may just find a particular region that had been overlooked, and it’s your duty to check it. In fact trying to find such regions is quite valid scientific work. Or you can do it simply because you feel like it. But the community that will check your work must weight your results against the null hypothesis that can tested (that is, something that can be invalidated). Hope this is not too confusing and helps you understanding that scientists minds are not twisted, they are just practical people.

    And of course it is more fun to find something that everyone claimed was extinct, than something that people assumed was simply hiding.

  22. #22 P.M.Bryant
    March 18, 2006

    Thanks for sending me the articles. After going over them, I’ve posted about this issue myself. In short, I find the Cornell team’s analysis of the video and overall argument much stronger than Sibley’s, which appears to gloss over certain facts that their pileated hypothesis can’t account for.

    Whatever evidence has been discovered over this last winter (if any) will ultimately make this controversy moot, however.

  23. #23 P.M.Bryant
    March 18, 2006

    I want to also add that this isn’t just a battle over pixels, although that’s what Sibley’s paper would lead one to believe by itself. The wingbeat rate in the video is not a matter of a few pixels. Same for the direct flight pattern. Same for the independent sightings of numerous experienced individuals. None of these is absolute proof. Put together, though, they make a very suggestive, compelling case. So clearly, the search team has not found “nothing.”

    I’m still confused over the state of public knowledge of what the search team has found (if anything) this year. You say there is no new evidence out worth speaking of, but is that because the scientific team is assembling reports and analyzing them, putting whatever case they can together before releasing it (typical scientific process). Or has everything been released so far?

  24. #24 Mike S
    March 18, 2006

    I don’t think any of the researchers involved in the controversy have formed a null hypothesis that the bird exists, or are being biased by what they would prefer to believe. A null hypothesis must be rejectable, so it must be disprovable, and so the null hypothesis is required to be the position that the bird does not exist (rejectable by finding a specimen). What we see are normal differences in individuals’ judgement of whether the evidence is sufficient to reject the null. The evidence is clearly strong enough to motivate many researchers to spend resources on finding it, but the evidence is not strong enough for many scientists to responsibly reject the null and accept its existence. Where there’s doubt, it’s always preferable to incorrectly accept the null hypothesis than to incorrectly reject it.

  25. #25 Home Bird
    March 18, 2006

    Ciao de Gaia: Thank you very much for your very helpful and informative post. This thoroughly answers one portion of my question.

    The rest of my question has to do not with what scientists should or should not believe, based on the question of “burden of proof,” but what scientists desire to believe. Remember that I started with noticing several statements that said something like, “I want to believe the bird exists, but only if it does.” And not noticing the statement, “I don’t want to believe the bird is extinct, unless it is.” And this is what I found puzzling, if not worrisome. Surely, what one wants to believe or disbelieve need not be governed by the rules of scientific inquiry–or perhaps the scientific process becomes so second nature that it takes over, not only thought but desire.

    On the other hand, I will say that I may have simply read a non-representative sample all at once, when in fact there are plenty of scientists out there expressing the second sentiment and I just didn’t happen upon them at that particular time. It may have been a matter of my own perception. So I am willing to put my question aside for now, and hope that the bias I thought I was seeing was an illusion.

    I am coming to this issue as a conservationist, and from this standpoint it makes sense to give the bird the benefit of the doubt until the evidence for extinction is more compelling than it is now. The searching has not actually been done adequately and Sibley’s explanation does not work for me.

    P.M. Bryant: Thanks for your post and your comments, which articulate some of the same problems I have with Sibley’s article much better than I could have.

  26. #26 Caio de Gaia
    March 19, 2006

    Home Bird, you give too much credit to scientists playing their emotions. Scientists are like the rest of the world, they have their own prejudices, passions, and their vision on how the natural world should behave; and sometimes they tend to value too much their own research. That’s way a sceptical scientific community is needed to insure good science is done.

    You are probably right in that professional bias may play a role in the “desire” part. Most scientist are only “believers” if convinced by strong evidence.

    It’s obvious GrrlScientist and many people commenting here really wanted to see the bird alive. Note that all comments reveal sadness (the title of the post is a good example) at the evidence not being strong enough for us to believe that the identification is positive.

  27. #27 Home Bird
    March 19, 2006

    Caio de Gaia: Ah ha! So I am being overly analytical here after all! And you’re probably right, as I am analyzing language. The entire answer may simply be that scientists use language differently than I am used to in certain types of discourse. Thank you! All is revealed.

New comments have been disabled.