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Author | Topic: Lignin in red algae supports the Genesis days chronology? What about birds? | |||||||||||||||||||||||||||||||||||||||
PaulK Member Posts: 17888 Joined: Member Rating: 8.4 |
quote: This is just Scanisoriopteryx again which I have already answered. Some of the traits are questionable (notably the reversed hallucinations). Feduccia is known to be strongly biased, and there is a lot of interpretation going on. In the absence of objective information I’m not going to be convinced by Feduccia’s opinions - when he convinces enough other researchers then is the time to take notice of opinions.
quote: That’s a complete invention on your part. Scanisoriopteryx is not a bird and could date after archaeopteryx so it doesn’t do much to move the order back in time. For that you have to buy Feduccia’s theory wholesale - and even that isn’t going to get you the Carboniferous birds you want (let alone the Cambrian birds you would need to have them appear at the same time as fish!)
quote: Which split, and why is it relevant ? And just after is millions of years.
quote: In other words, in your hypothesis, birds are descended from land animals living in the Triassic, and split away from the dinosaur ancestors before the first dinosaurs. But let us note that you have not one single fossil bird earlier than archaeopteryx. And yet we do have at least one fossil coelurosaur predating it. Which is rather odd if coelurosaurs are descended from birds rather than vice versa.
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caffeine Member (Idle past 1220 days) Posts: 1800 From: Prague, Czech Republic Joined: |
But the 4 chambered heart belonging to dinosaurs actually backs up my point ( I did not notice it earlier). No it doesn't. Your point seems to be that dinosaurs are descended from birds; so in your view, dinosaurs, pterosaurs, birds and crocodilomorphs form a clade, and thus share certain features. According to everyone else, birds are nested within dinosaurs; but this means that birds, dinosaurs, pterosaurs and crocodilomorphs still form a clade, so they still share certain features. We're all agreed on what an archosaur is, as far as I can interpret your argument, so shared features of archosaurs are not a point in anyone's favour.
But they do. (hearts matter to the relationships of birds and dinosaurs) Here is a scientist that proposes a pre-dinosaur "crocodilomorph" creature that evolved into birds. That article's behind a paywall, and the introduction doesn't mention hearts. The only scientist quoted in the introduction was one of the main popularisers of the idea that birds are dinosaurs. Given that you mention you don't have a subscription either, why do you think this has anything to do with hearts?
Flying birds are unlikely to be buried, and they must be considered a candidate for much earlier dates, considering all the evidence. And yet the fossil record of birds has grown exponentially in recent years; with no hint of anything pre-Jurassic. Now, of course that doesn't prove that birds were not around earlier - such a thing is always possible. But it's possible for every lineage of organisms - what you have failed to provide is any reason to expect such a thing. Note the key difference with the butterfly situation. As your article itself points out; there was a phylogenetic reason to expect early butterflies; because the sister group to Lepidoptera is known from much earlier. The sister group to birds is not - maniraptorans are known only from the Jurassic. The main hypotheses for the origins or bird flight are that they evolve from arboreal dinosaurs like Scansoriopteryx, as you quote in a later post; or (the more popular view) from cursorial (running) dinosaurs. No-one has ever proposed birds evolving from an aquatic ancestor; and it's difficult to imagine a model of how that would work. Of course, that I can't come up with a plausible scenario doesn't say much, but the key point here is that you still haven't given us any reason why we should try to? All you have done so far is point out that our knowledge is not absolute; and tried to therefore argue that we could try to twist the evidence in such a way that it doesn't 100% rule out your strange scenario. But why should be entertain your scenario in the first place? What evidence is there for it?
I found this following the relevant part of Caffeine's Wikipedia paste.(...)
quote: I didn't paste anything from Wikipedia; but with regards to the quote - why do you think this helps your case? Birds are dinosaurs - why would the fact that dinosaurs are like birds help any argument to the contrary?
Secondly, it seems that ALL feathered dinosaurs (aside from Archaeopteryx) date from the same period as they are from the same Chinese formation. They are from the Barrremian stage of the Early Cretaceous? Correct me if I'm wrong. Well, that's controversial; since there are several claimed discoveries of feathers in dinosaurs elsewhere. The fossil deposits in Liaoning are of exceptional quality; which is why so much there is preserved that the arguments related to other fossil sites can be avoided. But you need to keep track of the arguments here. Your position requires dinosaurs to be descended from feathered birds. If there were no feathered dinosaur before the Cretaceous it doesn't help your position.
His theories are current and he published a 2014 journal article on the issue. NOT REFUTED AT ALL! The fact that someone is publishing recently is not relevant to the correctness of their views. Despite the fact that Feduccia is still publishing today; there is one thing he has not published - a cladistic analysis. The 'methods' section of that paper is the quite frankly hilarious length of 112 words. Even that's longer than necessary - I would have saved space and simply written 'we looked at the fossil' Now, looking at a fossil, or living organism, and searching for some key classificatory feature that would allow you to declare where it belongs on the tree of life is exactly how these things were figured out in the 1940s. Thankfully, science marches on, and a lot of bright minds have spent the last seven decades figuring a better way; using statistical techniques to try and avoid the simple mistake of simply searching for features to support a presupposed idea, which project Feduccia is still sadly involved in, Cladistic analyses all recover Scansoriopteyx as a theropod; usually as a maniraptoran.
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caffeine Member (Idle past 1220 days) Posts: 1800 From: Prague, Czech Republic Joined:
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I had not read this post before replying, since you post a lot of words. Having read it I felt the urge to expand on my post:
EDIT: Classification has more to do with man's convenience. The recognition of something having major features that clearly predate the origins of something else is the issue. It is origins and not arbitrary classification. No, that's not how it works. You're looking at 19 characters - 19! Whether they're correctly coded is irrelevant; as this is precisely the sort of cherry-picking to support a preconceived conclusion I mentioned in the previous post. Phylogenetic analysis is done with hundreds of characters, not 19. If simple numbers are enough to convince you, then have a look at this 2012 cladistic analysis of coelurosaurian theropods. I recommend this since it's open access; and since they conveniently include the character matrix in the same pdf as the article; even conveniently listing synapomorphies supporting each clade in their analysis. You can then entertain yourself looking through the 51 shared characters in their matrix that support scansoriopterygids as paravians.
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LamarkNewAge Member Posts: 2497 Joined: |
The more I respond to, the more I get ignored (PaulK, especially, is setting a record for ignoring everything, then claiming that he has covered an issue).
I desperately want to respond to every word from the last 3 posts, but it will just be ignored, so a response to EVERYTHING is unwise. Will have to be selective. I want to make a point as concerns molecular evolutionary science verses the fossil record. (to be ignored I am fairly confident) caffeine states:
quote: It works both ways, huh? caffeine states:
quote: I am trying to get at the rub of this situation. Visualize this: Archaeopteryx (now in the last week) dates to 152 million years ago. Some birds fossils might possibly date to around 160-165 million years (though possibly later). Feduccia and (Czerkas and Yuan) look at the period of, more or less, 230 million years ago. Let us just take the fully formed Archaeopteryx's date of 152 million years (which makes birds appear much later than they actually were and thus helps make people like Feduccia look as foolish as possible) and use that as a benchmark to allow the maximum quantitative advantage to the "birds were dinosaurs folks". So, subtract 152 million years from 230 million years and you have a 78 million year discrepancy for things actually happening (while SO FAR undetected in the fossil record) verses what people like Feduccia (and the late Czerkas) are saying. A 78 million year discrepancy. Is this scientifically reasonable? Look at molecular biology in just the last 100 million years.
quote: A 50 to 60 million year discrepancy in just the last 100-125 million years! Got that? Here is an attack on Feduccia (generally lacking in actual substance except for a sweep using the fossil cladistics issue)
quote: The biggest problem with this cladistics issue is that ignores the fact that some creatures can maintain the ability to reproduce (and thus blend in genes) 34 million years after separating, like some frogs have done. Early flying birds might have been part of a small number of rare types of creature that were constantly exchanging genes (reproducing) and over long distances too. There could have been something of a conservative genetic process going on, with less genetic isolation than typically happens with diverging species. Lots of hybrids and long lasting features. There would be LOTS of evolution going on, and speciation would have been broad (in like a million directions), but there would be lots of opportunity for older genetic types to last for a long time(with some real variation and evolution for sure) after the earlier "nascent stage(s)". Page 14 of your PDF link said this:
quote: Birds are being found earlier. It is recognized that they are difficult to find.
quote: And I note that the 13 pre Theropoda features in Scansoriopteryx are still being ignored.
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LamarkNewAge Member Posts: 2497 Joined: |
quote: But what about this? put this term into google: Joseph Brown, a graduate student at the University of Michigan in Ann Arbor BMC Biology birds molecular clock
quote: Birds existed more than 40 million years earlier than the fossils. You said:
quote: o.k. Here is Wikipedia:
quote: So 165 million plus 40 would be at least 205 million. Then you said.
quote: Scansoriopteryx - Wikipedia Look at this thing that you say isn't a bird. It has long feathers, NOT FUZZ. It could very well fly. And you already said you will ignore the 13 pre-theropoda features. (as well as the 6 bird features which you just said you will ignore and deny) Perhaps because the 13 features place it absolutely no later (and probably earlier) than the very early Theropoda period (231 million years ago)
quote: I am saying birds were probably flying BEFORE the Theropoda existed. Scanisoriopteryx was seen as a bird creature - that descended from a 220-235 million year old ancestral line - by the people who discovered and named it. The ones you want to ignore (and it wasn't Feduccia!).
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LamarkNewAge Member Posts: 2497 Joined: |
quote: O.K. but I still think that early flying birds (lets say the very earliest were only 250 million years ago, though I suspect it was earlier) would have been quite RADIANT and had a rather wide range of gene broadcasting, and we might have very well seen lots of inter-fertile hybrids constantly re-mixing gene's into one another. (and the inter-fertile species hybridizing would be a major issue with both EARLY FLYING birds mixing with each other plus the re-mixing in with the tree climbers they descended from ) Birds are radical hybridizers today, over 200 million years after they first existed with all the variation.
quote: 10%! Today! Back to a period when the mixing would be much greater: 250 million years ago. Overall, flying birds would have been relatively small in number, compared to other types of critters, but they would have been more uniform in their genetic code. I'm talking about the early days. Think of birds as having an early "inflation" period not unlike the universe having its early (rapid)inflation in the first trillionth of a second. It can explain a lot of the cladistic analysis from 150 million years ago. Remember the scansoriopteryx enigma (that many would prefer to ignore)? Here is a (abridged) work from the guys who named it.
quote: It seems that the evidence indicates that pre-theropod dinosaurs (or from their lines) have the features that the first true bird is most closely related to. But there are so many common features of theropoda (with the certain NOW EVIDENT earlier lines) that it is confusing. There was some sort of early radiation that spread so many common features. The enigmatic nature of those that escape rapid burial and fossilization , like flying birds (especially) plus the tree climbers, complicate the picture. We have molecular biology that can help clarify the picture. We have the Pterosaurs (very very closely related to the Theropoda, like 5-10 million years separation from the supposed "common ancestor) helping give us hints. We even have some strong fossil evidence. But there was some early cosmic inflation type of event that spread the genetic code with the similar features, and ones which stuck around for a while in certain divergent lines. EDIT to show more bird hybrid details.
quote: Remember that modern birds have existed for over 100 million years. They have lots of similarities. It isn't too much of a stretch to see that there could have been tons of striking similarities from 250 million years ago to 150 million years ago. But diversity too. And residual features and differing rates of evolution. And common features should be expected in Dinosaurs if Theropoda descended from birds.
quote: "Paravians" did have "scansoriopterygid" type ancestors. That is why they have such striking similarities. But the cladistics aren't perfect. They don't have all the fossils needed because there are those which we don't have (especially earlier ones, and especially not flying birds, though they existed) Don't forget that the fossil record lacks 999,999/1,000,000 of the horizontal variants/cousins (that is to say living creatures from the SAME year!) and that is a conservative estimate. Most years lack the bird fossils completely. Nevermind all the vertical ancestors/descendants from years before and after TOTALLY MISSING. On tips and nodes of the fossil tree are accurate. (edit removing supid link for PDF, sorry for 10 month post editing) Edited by LamarkNewAge, : No reason given. Edited by LamarkNewAge, : No reason given. Edited by LamarkNewAge, : No reason given.
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PaulK Member Posts: 17888 Joined: Member Rating: 8.4 |
quote: You have a habit of not clearly making points. But it is certainly false that even close to most of what you say is being ignored.
quote: It is not very reasonable if we Feduccia and co are right as I pointed out. Although the idea that the gap makes them look foolish rather than their own efforts to force the data to fit their ideas seems silly.
quote: But note that this refers to divergences within the birds, and that the ancestors found by that method would not have the full suite of distinctive characters. You don’t bother to actually make a point, however let us note that the time period is much smaller. Also that the new groups may have been relatively rare in that time. Feduccia et al propose that birds were successful enough to produce quite a range of theropod descendants - which turn up before birds!
quote: Note that this is not really a flaw in the article. It’s not even detailed enough to call it an implausible hypothesis. I think you will find that the frogs are pretty similar in appearance and that they represent a rare case. To propose something on a much greater scale, involving much more different creatures with no real evidence is little more than an excuse.
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Pressie Member (Idle past 171 days) Posts: 2103 From: Pretoria, SA Joined: |
I'm still trying to figure out why the subject of this thread (lignin) turned out to people going on about birds.
Edited by Pressie, : No reason given. Edited by Pressie, : No reason given.
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PaulK Member Posts: 17888 Joined: Member Rating: 8.4
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Because the lignin argument was so obviously stupid that not even LNA can bring himself to try and defend it.
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Pressie Member (Idle past 171 days) Posts: 2103 From: Pretoria, SA Joined: |
You mean that even with his/her mastering of the art of sophistry LNA couldn't even try to defend his/her ideas?
Edited by Pressie, : No reason given.
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LamarkNewAge Member Posts: 2497 Joined: |
I said:
quote: PaulK said:
quote: I put this search term into Google: birds hybridization rapid evolution fast I got a hit to a 2004 journal with this short abstract with this text, which indicates birds and amphibians actually (seem to?) have about the same pre-zygotic post-zygotic isolation.
quote: Can't be read but there is something cool. The "Literature Cited" has every citation in the journal article with a "google scholar" link. Very relevant issues are obvious, just from the citation text, and something we should all look at I suppose. The Just a moment... like said "Hybridization presents challenges to the reconstruction of phylogenies, formulation of biological species concepts and definitions". Now birds are said to be part of "dinosaurs", which (dinousaurs) are said to have begun to exist 230 million years ago, and which split off from a common ancestor with the Crocodile-type creatures 240 million years ago. Pterosaurs are said to have branch off from this 240 million year old common ancestor as well. One 240 million year old ancestor split just 10 million years before there was a distinctive crocodilian line of creatures and a distinctive dinosaur line BUT FROM A COMMON ANCESTOR. (I feel that birds would have already existed by this time and in fact might have been a type of creatures that already existed for AT LEAST several tens of millions of years already.) But, it is a fact that birds evolved much faster than Crocodiles. Crocodiles are 'stuck in the past': Genetic study shows reptiles are closely related to birds but their evolution is 'unusually slow' | Daily Mail Online I put "birds evolved faster than crocodiles" into google, but other terms would find broader comparisons (than just birds verses crocodiles) I suppose. It would make a lot of sense to see birds as creatures that evolved at a quicker pace than dinosaurs, so that they might look more recent, and dinosaurs might look older. But the original birds would be older. This site below gets it.
quote: It is good to get the important things right. Scansoriopteryx is important. And it is something that can't be ignored.
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LamarkNewAge Member Posts: 2497 Joined: |
quote: I am not so sure he says that, but it sounds like something close to what I said. I will only say (for now) that Pterosaurs are said to have come into existence at the exact same time as Dinosaurs, but there is only like 1 fossil found that dates before around 160 million years ago. (and it dates around 220 million years ago, and was discovered in 1973?) Correct me if I am wrong (and I could be). Put this into google. Google feduccia springer journal 2014 It has lots of references (and critical reviews? it seems so) to the recent journal by (the late) Czerkas and Feduccia Journal of OrnithologyOctober 2014, Volume 155, Issue 4, pp 841—851| Cite as Jurassic archosaur is a non-dinosaurian bird I will look into the substance of the criticisms. Understand that Feduccia is often attacked over OLD stuff like the digit 1-2-3- and 2-3-4 issue. Now he is attacked for not having a cladistic tree for hypothetical 200 million plus year old fossils that he proposes MIGHT BE FOUND one day. His arguments rest on later fossils (like around 170-120 million year old fossils, like Scansoriopteryx). But later fossils tell stories that can't be ignored.
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PaulK Member Posts: 17888 Joined: Member Rating: 8.4 |
quote: If he says that theropods are all descended from birds then it is certainly true. And if he restricts the presumed bird descendants then he starts to run into trouble explaining the evidence of relationships within the theropods.
quote: The graphical timeline of pterosaurs shows 8 known species from the Triassic, so you are certainly wrong. It was not exactly hard to find.
quote: Most of what that search finds is either of little or no relevance. (Springer’s Journal crops up quite a bit)
quote: From when that issue was being argued that was pretty much the best point he had... Feduccia is mainly attacked for insisting on his view when his evidence was very poor. You are going to need to show that he has good evidence now to overcome that. And has caffeine has shown he is still using poor arguments.
quote: False. He is being criticised for using a weak analysis using only 13 (likely cherry-picked) characters when a much more comprehensive analysis is available.
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PaulK Member Posts: 17888 Joined: Member Rating: 8.4 |
I guess I will be accused of ignoring this if I don’t reply even though it is worthless.
A slower rate of evolving hybrid infertility is hardly adequate, especially when the timescales are so large and the creatures involved anatomically diverse. The Daily Mail article - hardly a reliable resource - is talking about evolution after the dinosaurs died out, so it is certainly not directly applicable. The more so since the rates would be expected to be more similar in species closer to the common ancestor.
quote: Then I hope you will start trying.
quote: Or maybe it is just an oddity of no great significance. The scientists who carried out the cladistic analysis you object to our more work into getting it right than Feduccia. And yet you seem determined to ignore their work.
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LamarkNewAge Member Posts: 2497 Joined: |
quote: Start with this: mammals average 2-4 million years.
quote: I put "mammals post-zygotic isolation. years" into Google to find this. Birds seem to be in the tens of millions of years presently then (since ten times longer time to loose ability to have viable offspring)? The isolation of the creatures increases exponentially with time as opposed to linearly. The fewer flying reptile "birds" that exist, the much longer the genetic compatibility will be. The result will mean that there is much more likelihood that the genes will fan out and become relatively (compared to other creatures and compared to later descendants) uniform.
quote: So birds would take much longer than the present - 10 times longer than mammals 2-4 million infertility time scale - birds rate to have a genetic reproductive barrier to hybrids having viable offspring? So INSTEAD OF 20 MILLION YEARS (or whatever it is exactly on average today), more like 50 million years back in the time of the very first birds (and the first 50 million years after the naissance)?
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