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Post by Dinotoyforum on May 3, 2008 9:41:44 GMT
If birds did not evolve through a transitionary 'dinobird' stage, what ARE the origins of birds?
What is the alternative?
I can think of only two -
Birds evolved from a more basal group of reptiles, to which all the evidence is contrary, or -
Creationism
So, anti bird peeps - which of these options do you fancy? Are your a crazy creationist or are you just an evidence denier?
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Post by sbell on May 3, 2008 14:48:50 GMT
If birds did not evolve through a transitionary 'dinobird' stage, what ARE the origins of birds? What is the alternative? I can think of only two - Birds evolved from a more basal group of reptiles, to which all the evidence is contrary, or - Creationism So, anti bird peeps - which of these options do you fancy? Are your a crazy creationist or are you just an evidence denier? Do you really need to say "crazy" in front of "creationist"? I can't think of any time where "rational creationist" could ever honestly come up. |
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Post by Dinotoyforum on May 3, 2008 15:05:36 GMT
I wanted to make it clear that I'm not suggesting it as a sensible option.
You are right though - "the origin of birds is....magic!" isn't gonna cut it as a rational alternative hypothesis.
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Post by sbell on May 3, 2008 21:38:36 GMT
I wanted to make it clear that I'm not suggesting it as a sensible option. You are right though - "the origin of birds is....magic!" isn't gonna cut it as a rational alternative hypothesis. Not that a hypothesis that ignores the available evidence is any better! |
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Post by tomhet on May 5, 2008 16:39:46 GMT
"Others, such as Stephen Czerkas and Larry Martin have concluded that Caudipteryx is not a theropod dinosaur at all. They believe that Caudipteryx [...] is a flightless bird, and that birds evolved from non – dinosaurian archosaurs." I feel more comfortable with that explanation  |
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Post by Dinotoyforum on May 5, 2008 16:54:52 GMT
Where is the quote from?
Obviously, feeling comfortable has no bearing on whether something is true, but anyway, why do you feel more comfortable with that explanation?
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Post by tomhet on May 5, 2008 17:01:41 GMT
Where is the quote from? Obviously, feeling comfortable has no bearing on whether something is true, but anyway, why do you feel more comfortable with that explanation? The quote is from Wikipedia, I read it earlier today. I know feeling comfortable has nothing to do with it  |
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Post by Dinotoyforum on May 5, 2008 17:06:52 GMT
A further quote re: Czerkas from en.wikipedia.org/wiki/Archaeoraptor: "Stephen Czerkas builds a case for his controversial view that maniraptoran dinosaurs are secondarily flightless birds" Controversial indeed. In other words, Velociraptor and chums are derived birds, not dinosaurs. Actually, it's an alternative explanation for why maniraptorans HAD feathers. I think I now know why those three dots were included in your original post Let me fill in the gap from your quote and make this clear" "They believe that Caudipteryx [and Velociraptor and chums] is a flightless bird, and that birds [and Velociraptor] evolved from non – dinosaurian archosaurs." |
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Post by Dinotoyforum on May 5, 2008 17:12:13 GMT
Where is the quote from? Obviously, feeling comfortable has no bearing on whether something is true, but anyway, why do you feel more comfortable with that explanation? The quote is from Wikipedia, I read it earlier today. I know feeling comfortable has nothing to do with it But again, why do you feel more comfortable with that explanation? I'm confufddled  |
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Post by Dinotoyforum on May 5, 2008 17:18:22 GMT
I asked:
"If birds did not evolve through a transitionary 'dinobird' stage, what ARE the origins of birds?"
The alternative suggested by Tomhet does not negate a 'dinobird' stage, it just spins the transition on its head.
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Post by sbell on May 5, 2008 17:23:40 GMT
But here's the problem--birds are dinosaurs. They have the same features, skeletally, as theropods. Foramina in the hip joint for example. Furcula, for example. Their feet even look the same.
According to Czercas, birds evolved from a separate line, then secondarily evolved into maniraptors--perfectly reasonable, but where did that line come from? Within the dinosaurs. If instead he claims that birds evolved from a separate thecodont ancestor, then Maniraptors cannot be dinosaurs either--we now realize the error in creating paraphyletic groupings; taxonomy needs to be based on relationships. So the question comes back--if birds evolved into maniraptors, that's great. They are sister groups. They share an evolutionary node on a cladogram--they evolved from the same hypothetical ancestor, which branched at some point. But the maniraptors+birds had to come from somewhere. Maybe they share an ancestry with coelurosaurs. but they are still dinosaurs.
Or is Velociraptor not a dinosaur? Really?
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Post by tomhet on May 6, 2008 4:09:58 GMT
A further quote re: Czerkas from en.wikipedia.org/wiki/Archaeoraptor: "Stephen Czerkas builds a case for his controversial view that maniraptoran dinosaurs are secondarily flightless birds" Controversial indeed. In other words, Velociraptor and chums are derived birds, not dinosaurs. From the same article: "Two reviewers informed Science that; “the specimen was smuggled out of China and illegally purchased” and that the fossil had been "doctored" in China "to enhance its value."Science then rejected the paper. According to Sloan, Czerkas did not inform National Geographic about the details of the two rejections" He doesn't even have a degree! Czerkas doesn't seem like a reliable guy As for your question, why I feel more comfortable with that view, I guess I just hate all the hype over these miracle findings. As some pointed out (can't remember where), scientists tend to jump to conclusions. True, I haven't read enough about this whole business (in this crappy country all the scientific books are terribly dated :  but I feel a natural distrust against these media-driven findings. |
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Post by sbell on May 6, 2008 4:44:00 GMT
A further quote re: Czerkas from en.wikipedia.org/wiki/Archaeoraptor: "Stephen Czerkas builds a case for his controversial view that maniraptoran dinosaurs are secondarily flightless birds" Controversial indeed. In other words, Velociraptor and chums are derived birds, not dinosaurs. From the same article: "Two reviewers informed Science that; “the specimen was smuggled out of China and illegally purchased” and that the fossil had been "doctored" in China "to enhance its value."Science then rejected the paper. According to Sloan, Czerkas did not inform National Geographic about the details of the two rejections" He doesn't even have a degree! Czerkas doesn't seem like a reliable guy As for your question, why I feel more comfortable with that view, I guess I just hate all the hype over these miracle findings. As some pointed out (can't remember where), scientists tend to jump to conclusions. True, I haven't read enough about this whole business (in this crappy country all the scientific books are terribly dated : but I feel a natural distrust against these media-driven findings. Actually, PR departments and the media tend to jump to conclusions--or at least misunderstand conclusions (see: that chicken rex nonsense). But Czercas (an artist by training, but that is neither here nor there, there are some very good science artists), from what I've read from him, does not seem completely...I don't know, right? Like he's embarked on this quixotic quest to overturn what is becoming taxonomic consensus. Larry Martin, however, is an academic, and should probably know better. Of course, academia is no immunization against dogma or stubbornness (see Jack Horner's dogged persistence that T rex HAD to be an obligate scavenger? Of course, new findings cast doubt on one of his main lines of evidence--the olfactory region of the brain was actually relatively small, not enormous). |
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Post by crazycrowman on May 6, 2008 18:06:23 GMT
I have always though larry martin a KOOK. Hes in it with Fedducia, also a KOOK when it comes to bird pre-history.
And...Czercas...oy! First off, pulling together that kind of cash to buy a black market chinese fossil !!!... ?! A simple scanning through ebay will bring you HUNDREDS of fake fossils...from all over...."eggs" from the USA, "sabre cats" from "china", "trilobites" from Morocco....sure, theres some real stuff, but most of it...well...
I want to take this time here....to REMIND everyone, while Archeoraptor was indeed a "chimera" animal, it was not "forged" from stone, or drawn on or other such sillyness. Archeoraptor was Yanornis glued to the to the back end of a Microraptor.
Those were STILL 2 very important fossils in thier own right.
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but I feel a natural distrust against these media-driven findings.
