If you’ve been asleep since late April, you’ve missed a fascinating scientific discussion about the existence – or not – of the ivory-billed woodpecker.

First, some scientists from Cornell said they had evidence of the existence of the bird, believed extinct for decades. A 4-second-long video of the supposed woodpecker was posted online.

Scientists from Yale and Kansas University found the video unconvincing proof of the bird’s existence. They were near to publishing their doubts in a scientific journal when, in late July, the Cornell scientists sent them an unreleased sound recording that caused them to pull their paper.

The controversy, like a flare shot into the night sky, brings attention to many related stories.

One of those is pack journalism – why media leap all over stories like this one. Another is the role of scientific hunches in discovery. A third is what “extinction” means if we are able to drag some long-gone animal’s DNA out of mothballs and reinvent the thing.

Essays treating these and related subjects can be found at the KU Natural History Museum Web site at nhm.ku.edu.

The woodpecker debate is a nice illustration of how scientific debate works – when it works as it should.

Of course a case like this tends to make those of us who defend scientific experts and expertise a little defensive. We know skeptics will say, “See, your experts don’t know so much after all.”

I’m not here to argue that. I’m here to talk about what I’ll call scientific family values, which ruled in this case.

Discipline is one of those values. Scientists hold themselves and their peers to a high standard of proof. They occupy a mental space that seems cramped to many of us, one where “scraps of doubt” are permitted but a final, unchanging “truth” is never quite reached.

Flexibility is another scientific family value. When evidence seems scanty, scientists doubt. When they get sufficient evidence, they are convinced. And when new evidence appears, they revise and update.

Working openly and publicly is another value. Scientists submit their evidence to journals where peers can review it and decide whether it should be published. If it is, other peers can argue for or against it.

Flexibility and openness are part of the raw power of science but also a point of attack for those who dislike it.

“It’s just a theory,” say the opponents of science, using the word “theory” as if scientific ideas were some loopy hybrid of whimsy and carelessness.

Scientific ideas may be born in a flash, but they don’t stay there long. They add muscle based on evidence – or they die.

Scientists also acknowledge their limits when it comes to discussing some ideas. These ideas may be valid and interesting, but if no evidence can be deployed for or against them, science can’t really tackle them.

Should the doubters from Yale and KU be embarrassed at having expressed their doubts and then changing their minds when presented with the new audiotape?

No. They were acting according to scientific family values.

We live in a time when an unbending will and an unchanging mind are sometimes considered a sign of power.

Scientists don’t think that way. Neither do I. Changing your mind in light of new evidence isn’t shameful.

Stubborn refusal to do so is.

– Roger Martin is publications and features editor for the KU Center for Research. His commentaries on research can be found at www.ur.ku.edu. Martin’s e-mail address is rmartin@ku.edu.