Back to the Drawing Board: Birdosaurus Edition

June 12, 2009 by Keyser Söze | Filed under Amazing, Epistemology, Philosophy, Wonders of Nature.

Archaeopteryx.Facts

Anyone who’s watched PBS and/or the Discovery Channel for the past few decades knows that birds are the evolutionary descendants of dinosaurs. This conclusion is basically reached on the “facts” that a) dinosaurs couldn’t have caught those people in Jurassic Park if they’d been cold-blooded, generic and birds have the same sort of hips as one class of dinosaurs, medicine so the idea is that some warm-blooded dinosaurs “morphed” into birds, treat while the rest of them died out. The “proof” of this story is the fossil known as “archaeopteryx” (Greek for, the “old winged one”), a beast that looks like your garden-variety dinosaur, but if you look carefully, it’s got little feathers!

Well, not so fast, there, Charles Darwin, seems some paleontologists are now saying that this all a crock of shit:

Researchers at Oregon State University have made a fundamental new discovery about how birds breathe and have a lung capacity that allows for flight – and the finding means it’s unlikely that birds descended from any known theropod dinosaurs.

The conclusions add to other evolving evidence that may finally force many paleontologists to reconsider their long-held belief that modern birds are the direct descendants of ancient, meat-eating dinosaurs, OSU researchers say.

It’s been known for decades that the femur, or thigh bone in birds is largely fixed and makes birds into “knee runners,” unlike virtually all other land animals, the OSU experts say. What was just discovered, however, is that it’s this fixed position of bird bones and musculature that keeps their air-sac lung from collapsing when the bird inhales.

Warm-blooded birds need about 20 times more oxygen than cold-blooded reptiles, and have evolved a unique lung structure that allows for a high rate of gas exchange and high activity level. Their unusual thigh complex is what helps support the lung and prevent its collapse.

The implication, the researchers said, is that birds almost certainly did not descend from theropod dinosaurs, such as tyrannosaurus or allosaurus. The findings add to a growing body of evidence in the past two decades that challenge some of the most widely-held beliefs about animal evolution.

“For one thing, birds are found earlier in the fossil record than the dinosaurs they are supposed to have descended from,” Ruben said. “That’s a pretty serious problem, and there are other inconsistencies with the bird-from-dinosaur theories.

“But one of the primary reasons many scientists kept pointing to birds as having descended from dinosaurs was similarities in their lungs,” Ruben said. “However, theropod dinosaurs had a moving femur and therefore could not have had a lung that worked like that in birds. Their abdominal air sac, if they had one, would have collapsed. That undercuts a critical piece of supporting evidence for the dinosaur-bird link.

“A velociraptor did not just sprout feathers at some point and fly off into the sunset,” Ruben said.
The newest findings, the researchers said, are more consistent with birds having evolved separately from dinosaurs and developing their own unique characteristics, including feathers, wings and a unique lung and locomotion system.

There are some similarities between birds and dinosaurs, and it is possible, they said, that birds and dinosaurs may have shared a common ancestor, such as the small, reptilian “thecodonts,” which may then have evolved on separate evolutionary paths into birds, crocodiles and dinosaurs. The lung structure and physiology of crocodiles, in fact, is much more similar to dinosaurs than it is to birds.

Well, smack Keyser’s ass and call him a creationist! All those shows he’d seen made it seem as if this “Tweety Pie, meet archaeopteryx, archaeopteryx, meet Tweety Pie” thing was a done deal. Turns out that recognizing the facts and making sense out of them are two different things. Who’d a thunk?

Very long-time Lair readers may recall a post from the distant past about some woman’s “Kuhnian moment” in not recognizing that the dog she’d gotten back wasn’t actually hers, an accidental switch having been made with someone else’s dog. Even when the glitch was pointed out to her by the other owner, she refused to believe that Spot wasn’t Spot, despite the fact that Spot was acting weird. This absurd situation led Keyser to ruminate on the role played by paradigms in our evaluation of the world around us. Thomas S. Kuhn famously argued that science isn’t all “just the facts, ma’am.” Rather, scientists (or anybody else trying to make sense of a situation) start from basic preconceptions about the overall situation, and these preconceptions then not only predispose them to viewing the evidence one way or the other, but actually play a vital role in how they determine what the relevant data is likely to be and how they interpret what they see. The paradigm is so influential that scientists sometimes either misunderstand what they see or don’t even see it at all if what they see doesn’t fit in with the paradigm. But when there’s enough contradictory evidence, then the old paradigm breaks down and there’s a “shift” to a new one.

Well. Remember those feathers on the archaeopteryx fossil? Well, hold your horses, bone digger!

No good evidence exists that fossilized structures found in China and which some paleontologists claim are the earliest known rudimentary feathers were really feathers at all, a renowned ornithologist says. Instead, the fossilized patterns appear to be bits of decomposed skin and supporting tissues that just happen to resemble feathers to a modest degree.

Using powerful microscopes, the team examined the skin of modern reptiles, the effects of decomposition on skin and the fossil evidence relating to alleged feather progenitors, also known as “protofeathers.”

They found that fossilized patterns that resemble feathers somewhat also occur in fossils known not to be closely related to birds and hence are far more likely to be skin-related tissues, Feduccia said. Much of the confusion arose from the fact that in China in the same area, two sets of fossils were found. Some of these had true feathers and were indeed birds known as “microraptors,” while others did not and should not be considered birds at all.

Although a few artists depicted feathered dinosaurs as far back as the 1970s, Feduccia said the strongest case for feathered dinosaurs arose in 1996 with a small black and white photo of the early Cretaceous period small dinosaur Sinosauropteryx, which sported a coat of filamentous structures some called “dino-fuzz.”

“The photo subsequently appeared in various prominent publications as the long-sought ‘definitive’ evidence of dinosaur ‘feathers’ and that birds were descended from dinosaurs,” he said. “Yet no one ever bothered to provide evidence — either structural or biological — that these structures had anything to do with feathers. In our new work, we show that these and other filamentous structures were not protofeathers, but rather the remains of collagenous fiber meshworks that reinforced the skin.”
Belief in the existence of the “dino-fuzz feathers” caused some scientists to conclude that they served as insulation, and hence dinosaurs were warm-blooded.

Say it isn’t so, Dr. Grant! You mean the facts don’t actually “speak for themselves” as Grissom says so often on CSI: The First one? Note carefully that it says that even back in the 1970s artists were making pictures of “feathery” dinosaurs. It’s not that this (apparent) misrepresentation has any evidentiary value in itself. But where did these artists get the idea from? Surely they didn’t come up with it and then the scientists coincidentally “found” evidence to that effect. No, what this shows is that the paradigm of red-blooded birdosaurs was already clucking around back then.

Speaking of Grissom, Keyser finds the popular “paradigm” regarding police work interesting. Back in the day, Dets. Gannon and Friday solved cases the old-fashioned way: with personal investigative work. That was okay back in the ’50s, when the authorities were trusted, but along came all that counter-cultural stuff in the ’60s, and the cops were no longer the dutiful upholders of the law. By the 1990s, we had Det. Sipowitz coercing confessions out of the “perps” by smacking their heads into the table in the interrogation rooms and threatening to repeat the process if they didn’t sign a confession. Now, no one can reasonably accuse Keyesr of being “soft on crime,” but he always found those episodes of NYPD Blue deeply offensive. Naturally, in terms of the show, you knew from the start that the suspect was actually guilty, so there was supposed to be something satisfying in watching Sipowitz get around the “technicalities” of legalistic nonsense such as the presumption of innocence and the protections of the citizens against the coercive powers of the state as guaranteed by Fifth Amendment to the Constitution. Keyser always thought that it would be useful to have an episode where some innocent person that Sipowitz forced into confession then hanged himself and Sipowitz had to deal with the consequences of his actions (which would be particularly interesting if no one else knew and he had to sort it out himself). But, no, that would involve too much thinking on the part of the audience, so Sipowitz could happily force the desired result because he knew what was true.

But by the time the late ’90s rolled around, truth wasn’t to be trusted to humans at all. Instead, we get Grissom going around saying that the facts “speak for themselves.” No, they don’t! Even entirely objective “facts” (like the fact that if you mix ten grams of this and five grams of that, you get so much something and a different amount of something else) only “mean” something in terms of human analyses interpretations of these “facts.” The public seemingly is pleased with the idea that there are criminal labs where you can send stuff, and somehow the “results” guarantee a truthful result, without any substantive input from Friday or Sipowitz or even Grissom.

But that is of course entirely erroneous. The investigations of crimes involve not only a whole series of paradigms about how the evidence is to be collected and interpreted, but also an even bigger and more uncertain number regarding what humans do and how to assess their behavior.

Furthermore, while the scientific question of what happens when you mix ten grams of this and five of that is a temporally neutral phenomenon. That is, it should always hold true, and you can test the result time and again. But if you’re talking about a historical event (whether it’s who killed JonBenét or how did birds evolve), you can’t do it over again, and you can only speculate on what happened on the basis of partial and uncertain evidence. The only way you can actually know what happened to OJ Simpson’s ex-wife is if you did it or if you witnessed it. Otherwise, one is simply attempting to see it through a glass of varying degrees of darkness.

So the next time Algore or David Suzuki want to sell you on so-called anthropogenic global warming, you might want to check under the hood of their paradigm or kick the tires a few times. You never know. There might be a feathery dinosaur hidden in the trunk…

Archaeopteryx


2 Responses to “Back to the Drawing Board: Birdosaurus Edition”

  1. Anton Phibes says:

    The bottom picture is quite stunning, even by your considerable standards.

    Vulnavia would like to know where we can go and buy one of these delightful creatures. Alas I have had to disappoint her. Looks like we’ll have to settle for a phoenix instead.

  2. Keyser says:

    Glad you like the image (and do tender my felicitations to the lovely Vulnavia!).

    As for phoenices, you’ll probably find them as easily as all those unicorns that Obama promised… Sort of like a feathered dinosaur – a rara avis (so to speak!).

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