Since the question of looking for DNA evidence of Ivory-bill presence keeps popping up I asked Cornell directly what if anything was going on in that regard. Here's the pertinent part of the response I received, for those interested:
"... It is possible to make a positive ID by using DNA markers and we have been doing this, pulling feathers from scalings and testing them for DNA. In all cases, the feathers were from Pileated Woodpeckers. Extracting DNA in any other way, like saliva or foot prints, as you suspect, would not be possible.
One thing that has been discussed is to use a DNA vac to pull up material from the floor of a cavity. However, in order for this to be a reasonable thing to do, we'd have to have identified cavities that were quite likely otherwise this would not be in the least cost efficient."
Wednesday, February 15, 2006
Comment from Cornell on DNA testing
Here's a BirdForum post from Cyberthrush (the bold font is mine):
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6 comments:
It is possible to make a positive ID by using DNA markers and we have been doing this, pulling feathers from scalings and testing them for DNA. In all cases, the feathers were from Pileated Woodpeckers.
No surprise. Naturally, Cornell has been focusing what they believe are likely Ivory-Bill scalings. These are the type of scalings that get so many "true believers" excited (see Birdforum.) OK, so they keep seeing these tantalizing glimpses of Ivory-Bills, and they have to be feeding somewhere. But every time it can be PROVEN what was feeding at these "Ivory-Bill scalings", through photographs or close range obvervation through binoculars or through remote camera shots, EVERY TIME, its Pileated woodpeckers, not IBWOs.
Please note that the "wariness" excuse does not work with remote cameras, or DNA work on scalings.
Reality is that which, when you stop believing in it, doesn't go away. Philip K. Dick
All this does is futher dis-credit their ability to make a positive ID of anything. One of their very key elements, the scaling bark, that was made by the Ivorybill, now only has DNA from ALL Pileated Woodpeckers.
What, this Ivorybill also leaves no traces of them ever being somewhere at all, even after allmost tearing a tree down to the ground? I guess they can now add this detail to the list of all the other things this bird does differant from all the past studies that have been done and everything we have ever know about it!
But let us not forget, this is "Super Bird"!!!!!!!!!
All this does is futher dis-credit their ability to make a positive ID of anything. One of their very key elements, the scaling bark, that was made by the Ivorybill, now only has DNA from ALL Pileated Woodpeckers.
Who is "they"? I don't think Cornell ever really made this a "very key element". I'd say their key elements are the video, various sightings, and, to a much lesser extent, possible acoustic evidence.
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"Who is "they"? I don't think Cornell ever really made this a "very key element". I'd say their key elements are the video, various sightings, and, to a much lesser extent, possible acoustic evidence."
I was not refering to the DNA, I was refering to the scaling of the tree's. It along with the holes in the tree's have been presented to the public from the beginning as "Ivorybill evidence"! But as it stands now, when this evidence has been looked at more & "SCIENTIFIC" methods have been applied to conferm this asumption, it now only show proof to the opposite as it stands.
And as for the video, soundings, & sightings, they also are starting to fall to the same fait when "SCIENTIFIC" studies are being applied to them also. We have a video that 100% has to be a Ivorybill because a Pileated just does not look & do what is shown in the video, but now we have video of Pileated's doing just what they were not suppose to do, we have audio that is 100% the bird in question, but now we have other birds making the same sound that was suppose to be made only by the Ivorybill. And as for the sightings, well I will refer back to items 1 & 2, mis-ID's.
Now, you ask who is "They"?
Well, I will ask you, Who is "They" that presented all this 100% proof positive evidence in the first place?
No one has presented scaling or other foraging sign as anything remotely approaching definitive or "very key" evidence. It is in fact an active area of research to try to see if there is ANYTHING useful that can be gleaned from foraging sign. If you read through the bird forum posts you will see that the consensus is that so far no one has firmly identified anything that cannot be explained as pileated, except possibly the extra wide bill gouges in Arkansas, and even that is preliminary. And these are your so-called "true believers."
What this does demonstrate is that, when asked, Cornell was quite forthcoming with negative results in this case.
Cornell released this negative information after being directly asked, and not before.
I also wouldn't call the scaling a "key element" of Cornell's paper, but feeding sign is, perhaps, the major source of excitement in the believer camp.
And feeding sign is still being presented by Cornell as, at least, "possible evidence" of Ivory-Bills, and combined with the many "possible sightings" it stands as proof to many people. Rumor has it that foraging sign was a major component of the Arkansas Bird Records Committee's decision to accept Cornell's sightings.
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