Talk:Origin of birds

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Secondary fligthlessness in dromaeosaurs and the like, relationship of later birds with them versus Archaeopteryx[edit]

The article states "Paul also proposed that the bird ancestor of these groups was more advanced in its flight adaptations than Archaeopteryx. This would mean that Archaeopteryx is thus less closely related to extant birds than these dinosaurs are.[126]" The author may have indeed mentioned that he thought so, I don't know, but the first statement doesn't imply the latter. As far as I understand it, it could be that the cladistic branching was in the sequence of coelurosaur → ancestor branch of living birds → archaeopteryx → dromaeosaurs. That is, Archaeopteryx itself being an intermediate in the direction of flightlessness, thus less advanced in its flight adaptations than the ancestors of them both, but still closer to living birds, as it's not yet 100% flightless. Dromaeosaurs, being flightless, "unavoidably" would have had also ancestors with flight adaptations passing through "Archaeopteryx-like" levels, that is, if we're not positing saltationism or near-saltationism, a "blazing fast" loss of flight from a highly-advanced flight, without an intermediate state. And perhaps they could have retained different sets of derived advanced flight adaptation vestiges. If Archaeopteryx has traits that strongly hint its flight adaptations are necessarily ancestral, predictably distinct from what one would expect from having evolved slightly inferior flight adaptation from a "better", unknown, bird ancestor (like chickens did from possibly better known ancestors), it would be "extremely interesting" to have it mentioned. At least for nerds who have a weird extreme interest in this sort of thing. — Preceding unsigned comment added by 189.18.92.181 (talk) 19:24, 25 June 2017 (UTC)[reply]

You are of course right that there is a non sequitur and I'll adapt the text. The tree you give is indeed found by some modern analyses but Paul's hypothesis is much older. He in 1988 proposed that "dinobirds", with which he meant more or less the entire Maniraptora, were more derived than Archaeopteryx. So Archaeopteryx would then not be a basal member of the branch towards the Dromaeosauridae, but the Dromaeosauridae would be a basal group of the branch towards modern birds. This would explain why, despite being flightless (Microraptor had not been found yet in 1988), dromaeosaurids showed flight adaptations that were more advanced than those of Archaeopteryx, such as a keeled and ossified sternum, uncinate processes on the ribs, stiffer tail, a bowed ulna and a bowed third metacarpal. And according to Paul, oviraptorosaurs were even more advanced birds, what with their short toothless skulls, short tails and pygostyles. Paul also suggested that Archaeopteryx had lost some flight capability but this in his view would be related to it being an insular species, not as a forerunner of dromaeosaurids.--MWAK (talk) 05:33, 26 June 2017 (UTC)[reply]

Collagen too prominent in lead?[edit]

Really, is this collagen story that significant? Abductive (reasoning) 20:31, 25 August 2017 (UTC)[reply]

I'm torn. On one hand, it's pretty damn cool (scientific term), and it's a totally independent verification of the link between theropods and birds, which previously has been based on morphology alone (for obvious reasons). On the other, neat as that is, even in the total absence of this molecular data, the link would be iron-clad, so does it really deserve such a prominent place? I'm inclined towards the former, but not strongly. HCA (talk) 21:12, 25 August 2017 (UTC)[reply]
Two editors above feel that it is a false result. As a primary source, and one that has been challenged, it has to go. Abductive (reasoning) 03:21, 27 August 2017 (UTC)[reply]
It's reasonable to remove it from the lead. It is not reasonable to remove all references to DNA and proteins from the entire article. First of all, even if there were a scientific consensus that the research showing DNA and proteins had been refuted, it would still be justified to mention this research within the historical development of the topic. Secondly, when research is on-going and competing teams claim conflicting results, we, as Wikipedia, do not have to draw any conclusions about a scientific consensus. That would violate the NPOV principle.
As regards the first sentence, WP:BOLDTITLE rules: "the first occurrence of the title and significant alternative titles (...) are placed in bold". --MWAK (talk) 06:41, 27 August 2017 (UTC)[reply]
Note: Also 2 editors above. Consenus reached. Abductive (reasoning) 19:13, 1 September 2017 (UTC)[reply]
Abductive I strongly advise you to stop editing the article page this instant, before we have to get you entangled in the consequences of an edit war on a high-importance article. Please explain your reasoning here (I recommend you provide more than your personal opinion as evidence the removal is necessary). IJReid discuss 19:41, 1 September 2017 (UTC)[reply]
As you are no doubt aware, primary source material is often inappropriate for encyclopedia articles. In particular, Wikipedia has a system by which any editor can "challenge" a primary source. It then becomes incumbent upon those wishing to retain that material to provide secondary or tertiary sources that say what they wish the article to say. In the case of scientific sources, secondary and tertiary sources means review articles in journals such as Annual Review of Ecology, Evolution, and Systematics or meta-analyses.
Starting with "In the March 2005 issue of Science, Dr. Mary Higby Schweitzer and her team announced...". This is WP:RECENTISM, WP:BOOSTER, and most importantly is cited to itself. If you wish the name of the discoverer to be given prominence in an article, one must show that with an independent secondary source. All of the remaining paragraph is all cited to Schweitzer. The secondary sources not written by Schweitzer about Schweitzer's collagen work say things such as, "Dinosaurian Soft Tissues Interpreted as Bacterial Biofilms". How embarrassing.
So what should remain in the article? I say that enough people have heard this collagen story that it cannot be deleted entirely. So I appended collagen to the list of fanciful claims and left the references for interested readers to be able to get to the primary sources without thinking that Wikipedia sucks. Abductive (reasoning) 20:10, 1 September 2017 (UTC)[reply]
Yes, primary source material can be inappropriate. Like when I write a book UFOs in my Backyard and then use it as a source for the article Extraterrestrial garden friends. Emphatically not inappropriate are peer-reviewed scientific articles published in Science. You might take a purist stance and not use these as a source until they're mentioned in a technical review paper but that's not policy. And it's highly impractical. Of course, the, slight, recentist and boosting elements can be corrected. Also, the text does not claim that collagen survives for 67 million years; it merely claims that there is a study claiming that — and for our claim the paper containing this study is then the secondary source.
The real question should be: is this Undue Weight? I'd say it isn't, in view of the publicity given to this research. Obviously, papers critical of the research should be mentioned, safeguarding the NPOV. These very papers prove the notability.--MWAK (talk) 21:39, 1 September 2017 (UTC)[reply]
Let's not forget that primary sources play an inexorably quintessential role in paleontology articles. With an absolute insistence upon secondary sources, we end up with things like "Serikornis has only ever been mentioned in one published paper, and therefore it must be invalid!" Lythronaxargestes (talk | contribs) 22:44, 1 September 2017 (UTC)[reply]
That's your misinterpretation of the WP:PSTS WP:POLICY. You should be ashamed of yourself for stooping to this spurious argument. Wikipedia does not require that all primary sources be removed. I ask you to strike this comment as nonconstructive. Abductive (reasoning) 17:29, 3 September 2017 (UTC)[reply]
Here we have to understand that many scientific articles are both primary and secondary sources. They relate direct observation and are in that regard a primary source; but they almost always also contain "an author's analysis, evaluation, interpretation, or synthesis of the facts, evidence, concepts, and ideas taken from primary sources", e.g. from an author's field notes. An article naming a dinosaur is a primary source as regards the naming act, but a secondary source in its Discussion chapter.--MWAK (talk) 08:35, 4 September 2017 (UTC)[reply]
  • Abductive needs to realise that it doesn't matter whether one, two, or three hundred Wikipedia editors think a study is "shit", all that matters is whether it is validly published and peer-reviewed, widely covered, and not WP:fringe. He also needs to calm down and remember WP:civil, as this is not the first time I see him throwing irrelevant and highly disruptive expletives left and right. Dissenting views should of course be presented; we are supposed to present both sides of controversy, not hide them or be biased. FunkMonk (talk) 23:50, 1 September 2017 (UTC)[reply]
    • Tragically, you are incorrect. I stated that secondary sources think is is a mistaken result. Also, I left mention of the study in the article, with refs. What is in the article now is WP:UNDUE wright given the weakness of the result. Why, for example, is the DNA and hemoglobin given brief mention but the collagen (since discredited) given such loving detail? Abductive (reasoning) 17:33, 3 September 2017 (UTC)[reply]
Well, if you want, you can describe the DNA in loving detail too ;o). As regards the Undue Weight: yes, it is a contentious and controversial issue. Papers are still written pro and contra. This also means that such claims are still taken serious enough to bother about them. It's not a closed case. Also, as it represents a possible method to independently test phylogenetic relationships it merits a mention in this article — and then should be treated, as all subjects, in a correct way, in a careful exposition of the arguments. That hasn't been done yet, so I'll have a try at it.--MWAK (talk) 06:35, 4 September 2017 (UTC)[reply]

BAND[edit]

This article discusses the dissent known as BAND or Birds Are NOt Diosaurs, but does not mention its name. As far as I knw, there is nowhere in Wikipedia which explains this name. If the hypothesis is worthy of discussion, isn't it worthy of mentioning it by name? If not here, then where? (And that is not a rhetorical question.) Let me make it clear that I am not an advocate of BAND. I just think that Wikipedia should explain what BAND means, and this paragraph in this article gives the fullest descripton. TomS TDotO (talk) 13:52, 1 March 2019 (UTC)[reply]

I fear that you misunderstood the terminology. "BAND" is not the name of the hypothesis, but of the group propagating it. They form the BAND and are themselves the BANDits. The implicit informality of this parlance has always led to objections when mentioning it on Wikipedia. Maybe one day a scholarly work will be written on the entire phenomenon and a well-sourced lemma can be created...--MWAK (talk) 21:09, 1 March 2019 (UTC)[reply]
All the more reason to mention the "correct" meaning of "BAND". How many people are left in the dark, as I was, about BAND because of Wikipedia's neglect? Do yuu have a reference that I can cite? TomS TDotO (talk) 23:38, 1 March 2019 (UTC)[reply]
I feel that the situation is not quite so dramatic. The terms are used by insiders to the discussion. If you belong to the "inner circle", you know what these names mean. If you are not one of the initiated, you have no need of knowing them... Therefore the experts avoid the use of such terms in publications, which makes it difficult to source them properly. However, recently this paper has appeared: https://academic.oup.com/sysbio/advance-article/doi/10.1093/sysbio/syz010/5315532 --MWAK (talk) 07:50, 2 March 2019 (UTC)[reply]
And we now also have Darren Naish. 2021. "Birds Are Not Dinosaurs (or BAND)" p 23-27 in Dinopedia — A Brief Compendium of Dinosaur Lore. Princeton University Press. A book highly recommended to those desirous to be "in the know" :o).--MWAK (talk) 09:00, 14 June 2022 (UTC)[reply]

Hearts?[edit]

"Computed tomography (CT) scans conducted in 2000 of the chest cavity of a specimen of the ornithopod Thescelosaurus found the apparent remnants of complex four-chambered hearts, much like those found in today's mammals and birds." Did this one specimen really have more than one, or should the sentence read "remnants of a complex four-chambered heart"? 71.235.184.247 (talk) 20:56, 22 March 2019 (UTC)[reply]

The wording is indeed awkward. Worse, today the consensus is that the fossil does not preserve a heart. I'll remove the mention of it.--MWAK (talk) 07:57, 23 March 2019 (UTC)[reply]