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Post by Horridus on Feb 15, 2011 0:12:06 GMT
Maybe it is, but the point wasn't to prove that its closest relative is a chicken. They compared the supposed tissues with those of a chicken in order to show that they were basically the same thing, meaning that Tyrannosaurus had that birdlike feature. However, if that was true it would still NOT be a bird and its closest relative was NOT a chicken! Prove birds are dinosaurs? It's been done, over and over! You mean apart from all the skeletal features and the feathers?
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Post by paleofreak on Feb 15, 2011 0:13:23 GMT
Fresh doubts over T. rex chicken link Sorry, but that headline is nonsense. Of course there is a T.rex - chicken "link" (close evolutionary relatedness). This is very well stablished. Nobody is challenging it. What is being questioned is that T. rex protein could be recovered and sequenced. Not the "dino-bird link". The media, in general, misunderstood the issue. They wrote about some "ultimate proof" that birds were related to dinosaurs (there is overwhelming evidence), or even that Tyrannosaurus was the ancestor of the chicken (which is stupid).
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Post by lio99 on Feb 15, 2011 0:15:36 GMT
Maybe it is, but the point wasn't to prove that its closest relative is a chicken. They compared the supposed tissues with those of a chicken in order to show that they were basically the same thing, meaning that Tyrannosaurus had that birdlike feature. However, if that was true it would still NOT be a bird and its closest relative was NOT a chicken! Prove birds are dinosaurs? It's been done, over and over! You mean apart from all the skeletal features and the feathers? They are more closer two an ostrich than a chicken.
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Post by paleofreak on Feb 15, 2011 0:27:52 GMT
;D Okay prove birds are dinosaurs It's easy to prove. Simply read some literature on taxonomy and phylogenetics. You'll see that birds are consistly nested within Dinosauria, and classified as members of Dinosauria. Most used definitions of Dinosauria also splicitly include birds, so birds simply can't be non-dinosaurs The study showed that T.rex was closer to the chicken than to the alligator or the Anolis. Which is in perfect and boring harmony with the "mainstream" hypothesis on birds origins and dinosaur phylogeny. Of course that work didn't pretend to show that the chicken was closer to the T.rex than any other bird or dinosaur. If I remember well, the only birds included in the study were the chicken and the ostrich. Both equally distant to the rex.
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Tyrannosauron
Junior Member
Science cannot move forward without heaps!
Posts: 92
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Post by Tyrannosauron on Feb 15, 2011 1:34:52 GMT
;D Okay prove birds are dinosaurs It's easy to prove. Simply read some literature on taxonomy and phylogenetics. You'll see that birds are consistly nested within Dinosauria, and classified as members of Dinosauria. Most used definitions of Dinosauria also splicitly include birds, so birds simply can't be non-dinosaurs The study showed that T.rex was closer to the chicken than to the alligator or the Anolis. Which is in perfect and boring harmony with the "mainstream" hypothesis on birds origins and dinosaur phylogeny. Of course that work didn't pretend to show that the chicken was closer to the T.rex than any other bird or dinosaur. If I remember well, the only birds included in the study were the chicken and the ostrich. Both equally distant to the rex. The real problem is that taxonomy is a philosophical concept rather than an empirical one. If I use the term "dinosaur" to mean "all and only those animals descended from a common ancestor with a hole in its hip socket" (thus including birds within the extension of the term) and someone else denies that the term is defined that way, there really isn't any naturally-occurring fact that can decide the matter. That birds do or don't have a hole in the hip socket can be proved; that this means the term "dinosaur" should apply to them cannot. If someone wants to dig in his heels and refuse to accept that "dinosaur" refers to turkeys just as much as it refers to tyrannosaurs, there's nothing on Earth that can convince him otherwise. In the end, it comes down to a choice about the role of taxonomy. If the way we classify organisms should reflect evolutionary history, then birds have to be dinosaurs. If you don't accept that birds are dinosaurs, then you can't use evolution to explain why related taxa are similar to one another. (Incidentally, I think that this is the best way to fight creationism/ID theory in schools, because which kid out there wouldn't want to believe that there are living dinosaurs?)
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Post by stoneage on Feb 15, 2011 2:24:28 GMT
;D Okay prove birds are dinosaurs It's easy to prove. Simply read some literature on taxonomy and phylogenetics. You'll see that birds are consistly nested within Dinosauria, and classified as members of Dinosauria. Most used definitions of Dinosauria also splicitly include birds, so birds simply can't be non-dinosaurs The study showed that T.rex was closer to the chicken than to the alligator or the Anolis. Which is in perfect and boring harmony with the "mainstream" hypothesis on birds origins and dinosaur phylogeny. Of course that work didn't pretend to show that the chicken was closer to the T.rex than any other bird or dinosaur. If I remember well, the only birds included in the study were the chicken and the ostrich. Both equally distant to the rex. Okay, so you and Horridus support this study that proclaims the protein from a 68 million year old femur is closer to a chicken or ostrich then an alligator. I suppose now you and Horridus have proved the relationship without having to use claudistics. Even though no fossil bone of anything remotely as old has been shown to have these proteins. Why isn't everyone running around gathering other dinosaur bones to duplicate similiar results. And if as I suspect this is totally bogus, how did they come up with these results? I'll tell you how, because they came up with what they wanted and expected to find.
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Post by stoneage on Feb 15, 2011 2:32:47 GMT
;D Okay prove birds are dinosaurs It's easy to prove. Simply read some literature on taxonomy and phylogenetics. You'll see that birds are consistly nested within Dinosauria, and classified as members of Dinosauria. Most used definitions of Dinosauria also splicitly include birds, so birds simply can't be non-dinosaurs The study showed that T.rex was closer to the chicken than to the alligator or the Anolis. Which is in perfect and boring harmony with the "mainstream" hypothesis on birds origins and dinosaur phylogeny. Of course that work didn't pretend to show that the chicken was closer to the T.rex than any other bird or dinosaur. If I remember well, the only birds included in the study were the chicken and the ostrich. Both equally distant to the rex. I wasn't asking for you to prove birds are dinosaurs but that it was what the study was attempting to indicate.
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Post by paleofreak on Feb 15, 2011 7:37:42 GMT
I wasn't asking for you to prove birds are dinosaurs but that it was what the study was attempting to indicate. The study just attempted to show that "fossilized" molecules can be recovered and used in phylogenetic tests.
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Post by paleofreak on Feb 15, 2011 7:55:06 GMT
Okay, so you and Horridus support this study that proclaims the protein from a 68 million year old femur is closer to a chicken or ostrich then an alligator. I'm not "supporting" this study. I was trying to explain that the aim of this study was not to "prove" an evolutionary "link" between birds and dinosaurs. A close relation between birds and other dinos is a well proven hypothesis, and protein similarity is not a weird "claim", is a prediction of this hypothesis. So if the protein is there, everyone would expect more similarity between T.rex and chicken than between T.rex and alligator. I have not proved anything. But there are lots of scientists out there proving it for decades Why "everyone"? Bias, self deception and unconsciously manipulation are human defects that scientists also have. I don't share your strong suspicions, but if they are right, it wouldn't be new in the science proffesion.
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Post by paleofreak on Feb 15, 2011 10:19:35 GMT
If I use the term "dinosaur" to mean "all and only those animals descended from a common ancestor with a hole in its hip socket" (thus including birds within the extension of the term) and someone else denies that the term is defined that way (...) OK, but It doesn't matter at all if that person denies whatever he wants. What do matters is the consensus (or the controversies) within the community of scientific experts in the particular field, and their published work.
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Post by paleofreak on Feb 15, 2011 10:42:55 GMT
I'm sorry, in previous posts my mind mixed several studies and didn't realize that the first, controversial work of Asara et. al. (2007) was replicated, confirmed and extended in 2008:
Organ, C.L., Schweitzer, M.H., Zheng, W., Freimark, L.M., Cantley, L.C., Asara, J.M. (2008). Molecular Phylogenetics of Mastodon and Tyrannosaurus rex. Science, 320(5875), 499-499. DOI: 10.1126/science.1154284
And then, Mary H.Schweitzer et al succeeded again with an hadrosaur:
Mary H.Schweitzer et al., 2009. Biomolecular Characterization and Protein Sequences of the Campanian Hadrosaur B. canadensis. Science 1 May 2009: Vol. 324. no. 5927, pp. 626 - 631 DOI: 10.1126/science.1165069.
The protein of moderns birds and ancient dinosaurs matched in all of these studies.
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Post by Horridus on Feb 15, 2011 16:20:39 GMT
I didn't say I supported the study either, simply that you (Stoneage) had missed the point about what they were showing. And hey, I had no idea that the study had further been backed up, so thanks for the information Paleofreak.
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Post by foxilized on Feb 15, 2011 17:16:21 GMT
And if as I suspect this is totally bogus If your bogus report is true, I suppose you maintain it by some sort of theory about why would they want to manipulate the information in that particular way. What do you think this people gain on lying about birds being dinosaurs? Must be some huge conspiracy story behind it all, I'd love you to tell us. Please? I'll tell you how, because they came up with what they wanted and expected to find. Imo I don't find that to be reportable at all. Please correct me if I am wrong but isn't any scientifical experiment based on searching for something expected to be found? You just don't go to the field to discover any random thing. You go to dig in a particular sediment expecting to find a particular fossilized remain you already know there's chances of being there, or search for a paralellism on two different animal proteins because you have a theory on they two being related and want to find some proof to support it. They were succesful on the search for proofs, are you blaming them cause they were succesful? Anyway as Paleofreak mentioned in his neat clean languaje, if you are demanding the ultimate proof of birds/dinosaurs link you will never get it cause it simply doesn't exist. There are already thousand of irrefutable proofs out there just as there are thousands wich proof we are primates. Demanding a missing link sounds like a sort of desperate "holding a burning nail" effort to deny what's so obvious it doesn't even need to be defended.
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Post by paleofreak on Feb 15, 2011 20:00:20 GMT
They were succesful on the search for proofs, are you blaming them cause they were succesful? Well, If you are obtaining and analyzing an nonexistent protein, and you get precisely the expected result (chicken-like sequence), then the whole thing is quite suspicious, isn't it? Stoneage seems to believe that the protein's not there, so... he is being logical ;D
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Post by stoneage on Feb 16, 2011 3:56:32 GMT
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Post by paleofreak on Feb 16, 2011 7:41:08 GMT
Also Scott Woodward a microbiologist from BYU claims to have found DNA in some large 80 MY old bone fragments. The DNA was unlike anything alive today but was more similiar to mammal DNA, in particular whales, then it was to birds or reptiles or anything else. That's an earlier work (1995), soon dismissed as a mistake. The small fragment of DNA was proven human. There was contamination of the sample. This was proposed by Caro-Beth Stewart and Randall V. Collura (Nov. 30, 1995 issue of Nature), and confirmed by Hans Zischler (May 26, 1996 issue of Science)
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Post by Megaraptor on Feb 16, 2011 8:54:45 GMT
Birds. Are. Dinosaurs. Simple. As. That. @ Foxillized: Not if the study is bogus, which I don't think it is.
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Post by lio99 on Feb 16, 2011 8:59:52 GMT
Birds. Are. Dinosaurs. Simple. As. That. @ Foxillized: Not if the study is bogus, which I don't think it is. They were more closer to the raptors then the other dinosaurs.
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Post by Megaraptor on Feb 16, 2011 9:13:18 GMT
If by "raptors", you mean Manioraptorans, then yes, they are descended from "raptors". I also dislike how you say "were more closely related", as if they stop being related over time. You are always as closely or distantly related to everything as you were when you began to exist. And the fact of the matter is, that no matter how closely, or not, related to "other dinosaurs" birds were, the "others" are still dinosaurs too, and thus birds are related to them. No matter what you are, you never stop being what you descended from. Take Pachyrhinosaurus lakustai. That is a member of the genus Pachyrhinosaurus, which is in turn a member of the tribe Pachirinosaurini, in turn part of the subfamily Centrosaurinae, in turn a member of the family Ceratopsidae, which is in turn a member of the unranked clade Neoceratopsia, which is a part of the superfamily Ceratopsia, which is part of the infraorder Marginocephalia, in turn a member of the suborder Cerapoda, in turn a member of the order Ornithischia, in turn a member of the superorder Dinosauria, yada yada, so on and so forth, et cetera et cetera, wibbly wobbly timey wimey, thankyou for listening, you've been a great audience, I'll be here all week.
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Post by lio99 on Feb 16, 2011 9:33:10 GMT
yeah the Manioraptorans
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