The entrance to the bird exhibit at the Cincinnati zoo in Ohio has or had a sign that said: “Dinosaurs went extinct millions of years ago—or did they? No, birds are essentially modern short-tailed feathered dinosaurs.”
First of all, bird evolution is one of the most controversial areas in evolutionary paleontology and evolutionists often disagree and criticize each other.
We hear a lot of reports of feathered dinosaurs being found, but what you rarely hear, is that the main candidates are believed by many experts to simply be frayed collagen fibers, or hair like structures that could have supported a frill or crest like those on iguanas, or are on animals that are not dinosaurs, but flightless birds. The drawings are certainly not what we find; they are just the artists’ imagination.
Dr. Alan Feduccia, a world authority on birds and an evolutionist, along with his coworkers have presented a substantial body of evidence to support their view that there are, in fact, no known dinosaurs with feathers (they believe birds evolved from different reptiles called crocodilomorphs, but not dinosaurs).
And then you have ones like Archaeoraptor that was proven to be a hoax. Who knows how many times that will happen.
All these announcements of feathered dinosaurs cause a lot of media fanfare, but when they are refuted, there is scarcely a whimper in the media.
You may be thinking, “But what about Archaeopteryx? That has been used for years and years.” Archaeopteryx was a true perching bird with fully formed wings and flight feathers, as well as a large wishbone for the attachment of muscles used for the downstroke of the wings. Here are some artist’s ideas of what it might have looked like.
So what is all the fuss about; why is Archaeopteryx such an icon of dino-bird evolution? Well, it had teeth in the bill, claws on the wings, no keel on the breast bone, an unfused backbone, and a long bony tail, which are all characteristics most people associate with reptiles.
But as Dr. Gary Parker said, “...the reptile-like features are not really as reptile-like as you might suppose. The familiar ostrich, for example, has claws on its wings that are even more ‘reptile-like’ than those of Archaeopteryx. Several birds, such as the hoatzin, don’t have much of a keel. The penguin has unfused backbones and a bony tail. No living birds have socketed teeth, but some fossil birds do. Besides, some reptiles have teeth and some don’t, so the presence or absence of teeth is not particularly important in distinguishing the two groups.”
Dr. Alan Feduccia (like I said, an evolutionist, and by the way, one who doesn’t like creationists quoting him) said, “Paleontologists have tried to turn Archaeopteryx into an earth-bound, feathered dinosaur. But it’s not. It is a bird, a perching bird. And no amount of ‘paleobabble’ is going to change that.”
On top of that, scientists have found fossils of what they would call “true birds” in layers of rock that they date as being older than Archaeopteryx. That presents a problem for them.
I believe Archaeopteryx was something of a mosaic like a bat or platypus. Similar structures can just as easily point to a common designer. God knew what designs would work well in multiple animals.
What they need to find, is a fossil showing scales turning into feathers, or a leg turning into a wing, or the reptile lung turning into the avian lung. How you can take a “two-way” reptile lung and evolve it into a fully functional “one-way” bird lung without causing extinction of the species is quite a conundrum.
And there are other problems. Feduccia and his team studied bird embryos under a microscope and published their study in the journal Science. They reported, “New research shows that birds lack the embryonic thumb that dinosaurs had, suggesting that it is ‘almost impossible’ for the species to be closely related.”
And then there is the new T-rex and chicken link based on that T-rex soft tissue they found. But as usual, we don’t ever get to hear the whole story. Dr. David DeWitt commented on this and said, “Of all the organisms in the sequence database, the one that matched T. rex the closest was the chicken. Now, before assuming that this would be strong evidence that birds are related to dinosaurs, it must be put into perspective. The sequence similarity between the T. rex and the chicken was 58%, while it was only 51% similar to both frogs and newts. This compares with a reported 81% similarity between humans and frogs, and 97% between humans and cows. Moreover, while some of the peptide fragments showed sequence matches to chickens, others matched frog, or newt, or even fish and mice. The authors did point out that not all organisms are in the database. Although the chicken was the closest match from the database, it is possible that animals not included could be a closer match. Regardless, such similarity does not prove that the organisms shared an evolutionary ancestor.”
There is no credible evidence that dinosaurs evolved into birds. As the Lingham-Soliar team said, “What is missing are the links between Archaeopteryx and other species that would show how it evolved. But [the] fossil record is frustratingly small and incomplete and this is why debate has been so fierce.” I think the fossil record is just fine; it teaches us that dinosaurs have always been dinosaurs and birds have always been birds.
I like what Dr. Jonathan Sarfati said, “It is perfectly in order for creationists to cite Feduccia’s devastating criticism against the idea that birds evolved ‘ground up’ from running dinosaurs (the cursorial theory). But the dino-to-bird advocates counter with equally powerful arguments against Feduccia’s ‘trees-down’ (arboreal) theory. The evidence indicates that the critics are both right—birds did not evolve either from running dinos or from tree-living mini-crocodiles. In fact, birds did not evolve from non-birds at all!”
2007-09-05 18:52:18
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answer #3
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answered by Questioner 7
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