Skip to comments.Dinosaur-Bird Flap Ruffles Feathers
Posted on 10/11/2005 4:07:11 AM PDT by mlc9852
MONDAY, Oct. 10 (HealthDay News) -- Head to the American Museum of Natural History's Web site, and you'll see the major draw this fall is a splashy exhibit on dinosaurs.
And not just any dinosaurs, but two-legged carnivorous, feathered "theropods" like the 30-inch-tall Bambiraptor -- somewhat less cuddly than its namesake.
The heyday of the theropods, which included scaly terrors like T. rex and velociraptor, stretched from the late Triassic (220 million years ago) to the late Cretaceous (65 million years ago) periods.
(Excerpt) Read more at news.yahoo.com ...
That's not the context of Patterson's alledged out of context quote. It's about the gaps in the fossil record. Those pesky gaps that prompted Gould and Eldredge to advance the theory of "Punctuated Equilibrium".
---excerpt Talk Origins ----
"Anyone who has actually read the book can hardly say that Patterson believed in the absence of transitional forms". Lionel Thevnissen.
----excerpt Talk Origins------
"I fully agree with your comments on the lack of direct illustration of evolutionary transitions in my book. If I knew of any, fossil or living, I would certainly have included them. . .I will lay it on the line, There is not one such fossil for which one might make a watertight argument." -- Dr. Colin Patterson, senior paleontologist at the British Museum of Natural History.
From the Talk Origin article it becomes clear that the "out of context" controversy is animated by comparing apples with oranges.
"Patterson believed" and "There is not one such fossil for which one might make a watertight argument." are the giveaway phrases in Thevnissen's Talk Origins argument.
Sunderland doesn't question Patterson's belief in Darwin's theory of gradual change over long time spans. He asks for hard evidence. Patterson says he has none. In addition Patterson speculates that there may be a problem with the fossil record. That's in understatement IMO.
This problem was pointed out by Jay Gould and Niles Eldredge in a paper initiated some years ago. It was also pointed out by Darwin himself.
Sorry, I don't agree. Suggesting Patterson believes there is no hard evidence is a misuse of the quote, contradicted by both Patterson's general scholarly work as well as his specific response to the quote given in the talk.origins file.
That's not what I said.
I'm saying that the Talk Origins Article is suggesting that Patterson believes in Darwin's gradualism and it's attendant micro transitional changes in life form. Transitional life forms that fill the infamous "gaps". But he knows of no hard evidence from the fossil record that can support his belief.
Hard evidence in this context is not referring to isolated quasi factoids and speculations (i.e. Zebra to Tapir to Rhinoceros) but to real comprehensive evidence. A plethora of evidence from the fossil record indicating Darwin's gradualism is fact.
Darwin postulated a continuous system of gradual micro changes over long time spans. But the fossil record doesn't support this approach.
It's a discrete system (i.e. discontinuous).
Not quite. Darwin said that the continuum of micro changes existed, over time, for each species, but he understood clearly why the fossil record would be spotty.
The Origin of Species, by Darwin: Chapter 9 - On the Imperfection of the Geological Record.
Taxonomy, Transitional Forms, and the Fossil Record. What the fossil record is all about.
And it is spotty. Discontinuous is a better word. And there lies the problem. The fossil record has gaps for what ever reason. The Darwinians will give their rational for why it is so. The creationists and punk eeks will give theirs. And the controversy will continue.
Each side committed to their favorite theory. Interpreting self selected facts and quasi facts to support their side. And telling 'just so narratives' along the way.
And it is spotty. Discontinuous is a better word.
What you're missing is that it's discontinuous IN A WAY CONSISTENT WITH EVOLUTIONARY BIOLOGY. It is NOT discontinous in a way consistent with creationism. Yet again, this *support* evolutionary biology and falsifies a non-evolutionary creationism. Furthermore, periodically nwe fossils are found which help fill in some of the discontinuities, and these consistently MATCH THE PREDICTIONS OF EVOLUTIONARY BIOLOGY. This again is stunning confirmation that evolutionary biology is correct, and creationism is wrong (see my earlier posts about the many and varied fossils which have been found fulfilling predictions of evolutionary biology, and *refuting* the confident statements of creationists about how such "missing links" would forever remain "missing" because evolution was off on the wrong track.)
And there lies the problem.
It's only a problem for creationism.
The fossil record has gaps for what ever reason.
It has gaps for the reasons stated by science, as confirmed by the fact that the gaps are of the type and nature one would expect if the scientific explanation was correct, AND confirmed by the fact that when new fossils aer fond, they help fill in the gaps in ways that science predicts they will.
Since the The Darwinians will give their rational for why it is so.
...and new findings keep confirming that the "Darwinian rationale" is the correct one. This is a classic case of theory making predictions, and the predictions being subsequently validated, which confirms the theory.
The creationists and punk eeks will give theirs.
...and new findings keep *falsifying* the creationist rationale.
And the controversy will continue.
...only among people who don't actually examine the evidence, or willfully choose to ignore it.
Each side committed to their favorite theory.
Biologists because they follow the evidence where it leads, and creationists because they ignore the evidence and believe what they want to believe. Also, creationism does not actually rise to the level of a "theory", don't pretend that it does.
Interpreting self selected facts and quasi facts to support their side. And telling 'just so narratives' along the way.
You're describing the creationists, not the scientists. The scientists develop theories which best fit *all* the actual evidence -- using "self selected facts" is not an option in science. It is, however, de riguer in creationism.
Finally, by focussing obsessively on the *gaps*, you appear to be intentionally trying to draw attention away from the way in which the "nongaps" (the actual evidence which *has* been acquired) overwhelmingly draws an unmistakable pattern of evolutionary development and interrelatedness.
There will always be gaps, in ALL collections of human knowledge. The wise man learns the lesson told by the information we *do* have -- and in the case of evolutionary biology, it is a MASSIVE amount of information -- rather than fixate on the "holes" and mumble about, "well, what might be in the holes *could* be argued either way"... Fine, but what about the vast sections of the picture where we *do* have the pieces already? These point overwhelmingly to evolution.
Here's a post of mine from last year that deals with the same fallacious "focus on the gaps, not on the data that has been acquired" hand-waving:
There are billions and billions of gaps.
Not that I've noticed. Perhaps you could support your claim by naming, say, twenty million or so of them. We'll wait.
But I see what you're driving at. You're saying that it would be premature for anyone to see any sort of pattern at all in the following, due to all those "gaps", so it must be just a meaningless scattering of dots, and no rational person would conclude that the dots indicate anything, or that closely spaced dots appearing to form a lines are anything more than a wild coincidence, since those pesky "gaps" preclude any sort of sensible connection whatsoever:
You're saying that until every single gap is filled, you can't possibly draw any conclusions from the relative positioning of the available data samplings, even when they seem to form clear patterns of connections, and fall into recognizable, meaningful results:
You're saying that it's impossible for the distribution and pattern of data points to suggest an underlying form, because the "gaps" between the data points could possibly make the final picture turn out to be something entirely different, if eventually filled in, and that the indications of the current data points mean nothing, and may just give the chance *appearance* of pattern, which anyone can mentally form into any shape through mental bias:
You're saying that while some of the pieces of the puzzle are still missing, it would be foolish, presumptuous, or impossible to make informed assumptions about what the "big picture" indicates, and what the missing pieces might look like:
I understand your point -- it's a common one among creationists/anti-evolutionists. I just think it's naive and goofy, that's all.
Are Birds Really Dinosaurs?
Ask your average paleontologist who is familiar with the phylogeny of vertebrates and they will probably tell you that yes, birds (avians) are dinosaurs. Using proper terminology, birds are avian dinosaurs; other dinosaurs are non-avian dinosaurs, and (strange as it may sound) birds are technically considered reptiles. Overly technical? Just semantics? Perhaps, but still good science. In fact, the evidence is overwhelmingly in favor of birds being the descendants of a maniraptoran dinosaur, probably something similar (but not identical) to a small dromaeosaur. What is this evidence?
We'll spare you the exhaustive amount of available cladistic studies; those alone would make a large book if compiled. Dr. Jacques Gauthier, during his time as a graduate student of Professor Kevin Padian here at Berkeley, did his dissertation research on this subject, creating the first well accepted, detailed phylogeny of the diapsids. His work provided strong, compelling support for the theory that birds are theropod dinosaurs.
If we look back into the history of the issue, it is apparent that many comparative anatomists during the 16th through 19th centuries noticed that birds were very similar to traditional reptiles. In 1860, shortly after the publication of Charles Darwin's influential work On the Origin of Species By Means of Natural Selection, a quarry worker in Germany spotted an unusual fossil in the limestone of the Solnhofen Formation (late Jurassic period). This fossil turned out to be the famous 'London specimen' of Archaeopteryx lithographica. It was a beautiful example of a "transitional form" between two vertebrate groups (traditional reptiles and birds); just what Darwin expected would eventually be found. Archaeopteryx, generally accepted as being the oldest known bird, is an important link between birds and other coelurosaurs that has helped to illuminate the evolutionary history (phylogeny) of the group. It is not widely held to be the ancestor of all living birds; this is a common misconception. In fact, recent expeditions in China, Mongolia, Madagascar, Argentina, and elsewhere may uncover dinosaurs that usurp the "urvogel" status of Archaeopteryx.
Many scientists, including Thomas Henry Huxley (a staunch suppporter of Darwin), saw incredible similarities between birds and the theropod dinosaurs (especially the coelurosaurs). Others since Huxley also hinted at the striking resemblances. However, birds were still not well accepted as dinosaur descendants such hypotheses as A. Walker's "crocodylomorph" ancestor and G. Heilman's "thecodont" ancestor held sway for most of the 19th and 20th century, or else birds were simply dismissed as originating from some unknown reptile that didn't matter anyway. That would change. Dr. J.H. Ostrom's 1969 description of Deinonychus antirrhopus and its similarities to Archaeopteryx was the major step: his work since the 1970's has provided the impetus for a paradigm shift in paleontologists' visions of the origin of birds and the evolution of flight. Dr. Gauthier's cladistic work in the mid-1980's provided the best analytical systematic support for the theory that birds are the descendants of dinosaurs. Several independent analyses by other scientists have repeatedly upheld Gauthier's results. Today the important issue seems to be specifically which dinosaurs are the closest relatives of birds. The controversy over the dinosaurian status of birds had its heyday in the 1970's, but the coverage of the issue today by the press might make you think it was still a problematic matter. For those that have actually seen the relevant specimens and considered all of the relevant data (which is a basic procedure for any scientist), it is becoming increasingly difficult to draw the line between "bird" and "non-avian dinosaur".
Some researchers today do not agree that dinosaurs gave rise to birds, and are working to falsify this theory, but so far the evidence for the theory has swamped their efforts. If they were to conclusively establish that birds are more likely descended from another group (Crocodylomorpha, the group containing crocodiles, has been suggested), that would be a major upheaval in our knowledge of phylogeny. One single well-preserved fossil bird unequivocably of Triassic age might shed some doubt on the theory of the maniraptoran affinities of birds. That would be a major find. Some bird-like fossils have been presented as Triassic birds, but so far have not held up under peer review. Such is the dynamic nature of science.
So you may be thinking now, what are these striking resemblances between birds and other dinosaurs? The ratite birds, three of which are pictured in this article, are quite similar to theropod dinosaurs. Some of the similarities may be superficial, but others may be too obvious to dismiss, and in any case all available data must be considered. We'll start with the "reptilian" similarities of birds. Like all other reptiles, birds have scales (feathers are produced by tissues similar to those that produce scales, and birds have scales on their feet). Also, birds lay eggs like other reptiles. The soft anatomy (musculature, brain, heart, and other organs) all are fairly similar; birds are more derived in some aspects owing partially to their endothermic metabolism and their ability to fly. There are numerous skeletal resemblances between birds and other reptiles; these form the basis of the cladistic analyses done by Gauthier and others.
Coelurosaurian dinosaurs are thought to be the closest relatives of birds, in fact, birds are considered to be coelurosaurs. This is based on Gauthier's and others' cladistic analyses of the skeletal morphology of these animals. Bones are used because bones are normally the only features preserved in the fossil record. The first birds shared the following major skeletal characteristics with many coelurosaurian dinosaurs (especially those of their own clade, the Maniraptora, which includes Velociraptor):
Pubis (one of the three bones making up the vertebrate pelvis) shifted from an anterior to a more posterior orientation (see Saurischia), and bearing a small distal "boot".
Elongated arms and forelimbs and clawed manus (hands).
Large orbits (eye openings in the skull).
Flexible wrist with a semi-lunate carpal (wrist bone).
Hollow, thin-walled bones.
3-fingered opposable grasping manus (hand), 4-toed pes (foot); but supported by 3 main toes.
Reduced, posteriorly stiffened tail.
Elongated metatarsals (bones of the feet between the ankle and toes).
S-shaped curved neck.
Erect, digitgrade (ankle held well off the ground) stance with feet postitioned directly below the body.
Similar eggshell microstructure.
Teeth with a constriction between the root and the crown.
Functional basis for wing power stroke present in arms and pectoral girdle (during motion, the arms were swung down and forward, then up and backwards, describing a "figure-eight" when viewed laterally).
Expanded pneumatic sinuses in the skull.
Five or more vertebrae incorporated into the sacrum (hip).
Straplike scapula (shoulder blade).
Clavicles (collarbone) fused to form a furcula (wishbone).
Hingelike ankle joint, with movement mostly restricted to the fore-aft plane.
Secondary bony palate (nostrils open posteriorly in throat).
Possibly feathers... this awaits more study. Small, possibly feathered dinosaurs were recently found in China. It appears that many coelurosaurs were cloaked in an external fibrous covering that could be called "protofeathers."
Objections to the theory of the dinosaurian origin of birds
Some researchcers have raised issues that may seem to make the theropod origin of birds difficult to support, but these difficulties are more illusory than substantial. One proposed difficulty is the gap in the fossil record between the first known bird (Late Jurassic) and the dromaeosaurs, probable sister group of birds (Early Cretaceous). This overlooks the blatant fact that other maniraptoran coelurosaurs, such as Ornitholestes, Coelurus, and Compsognathus, are known from strata of Late Jurassic age. If other maniraptorans were there, it logically follows that the ancestors of dromaeosaurs were there. Fragmentary remains of possible dromaeosaurs are also known from the Late Jurassic.
Other arguments, such as the putative differences between theropod and bird finger development, or lung morphology, or ankle bone morphology, all stumble on the lack of relevant data on extinct theropods, misinterpretations of anatomy, simplifying assumptions about developmental flexibility, and/or speculations about convergence, biomechanics, or selective pressures. The opponents of the theropod hypothesis refuse to propose an alternative hypothesis that is falsifiable. This is probably because there are no other suitable candidates for avian ancestors. "Thecodonts" are often promoted as such, but this is an obfuscatory, antiquated term for a hodgepodge of poorly understood and paraphyletic, undiagnosible reptiles. The problems cited by such opponents for theropods are often more serious for the "thecodont" pseudo-hypothesis. Finally, such opponents also refuse to use the methods and evidence normally accepted by comparative evolutionary biologists, such as phylogenetic systematics and parsimony. They rely more on an "intuitive approach," which is not a method at all but just an untestable gestalt impression laden with assumptions about how evolution must work.
The "controversy" remains an interest more of the press than the general scientific community. There are more interesting issues for scientists to explore, such as how flight performance changed in birds, what the earliest function(s) of feathers was(were), when endothermy arose in some archosaurs, which group of theropods was ancestral to birds, how theropod ecology changed with the acquisition of flight, why some bird groups survived the Cretaceous extinction of other dinosaurs, etc.
Without its feathers, Archaeopteryx looks much like a small coelurosaur such as a dromaeosaurid or troodontid.
The facts are resoundingly in support of a maniraptoran origin for birds; certainly a theropodan origin at the very least. So when you see a hawk diving to snatch a dove, or an egret darting for fish, or an ostrich dashing across the African savanna, know that you are gaining some insight into what the extinct dinosaurs were like. However, do note that extant (living) birds are quite different from extinct dinosaurs in many ways, so it's not safe to assume that all dinosaurs are the same. For that matter, extant birds are quite different from Jurassic and Cretaceous birds. Time passes, the environment changes... life evolves. Extant birds have been separated evolutionarily from the other coelurosaurian dinosaurs for some 150 million years, so they do look, act, and function quite differently, but science has shown us that they are closely linked by their common evolutionary history.
Of course in our polite, politically correct society we no longer laugh at the insane, we call them "Doctor" and shake our heads knowingly or is it condencendlingly, when they say, with a straight face, "Billions and billions of years ago, after the acid rained on the rock and diosaurs got tired of having diaosaurs they started branching out and had birds.
They had these birds by mating with other dinosaurs, but they had gold finches isntead of T-Rex's.
Well I guess we should thank God they haven't tried to convince us that it was birds that came first.
Could be these guys are the answer to 2 Timothy 3:1-5. And Peters scoffers.
Do I detect envy and jealousy in your post?
Obviously all the home-schooled in the group and you never got a proper education in evolutionary biology or you wouldn't be making such stupid posts.
Not if you are a "Soldier of God"
Two bambiraptors battle over territory.
Earth to Earth ...
And you don't know otherwise.
We have the fossil record our models of evolution and geology tell us we should have. Nevertheless, we also have a lot of naysaying Witch Doctors doing strawman arguments which Darwin anticipated and answered in 1859. This is unfortunate and the reasons for it have nothing to do with science. We have the fossil record our models of evolution and geology tell us we should have. It doesn't stop people whose religion compels them to misrepresent science, but we have the fossil record our models of evolution and geology tell us we should have. Some people will be back again dumb as a stump with the same garbage no matter how often their arguments are discredited, but ...
Only ONE side has a theory.
Frankly, I am seriously unimpressed with those kids. Dishonest and major bad manners. I would hope homeschooling would produce a better result.
Find a book called the BIBLE, ask the HOLY SPIRIT to help increase your faith, and study BIBLE diligently. If your are sincere, GOD WILL allow you to understand what you are now not able to understand.
If you want miracles from ME, sorry, I'm just a mortal man.
Now you know.
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