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Author Topic:   Lignin in red algae supports the Genesis days chronology? What about birds?
PaulK
Member
Posts: 14563
Joined: 01-10-2003
Member Rating: 2.1


Message 31 of 62 (827677)
01-29-2018 1:23 PM
Reply to: Message 29 by LamarkNewAge
01-29-2018 8:11 AM


Re: LamarckNewAge resorts to pretending responses don’t exist
quote:

Here is the complete list of PRE THEROPOD characteristics .from the 2012 book.

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:

PaulK is dancing around the issue that Archaeopteryx is STILL the oldest, so he can't make an issue out of this creature dating AFTER the fully formed bird. The order is still earlier, based on the evidence.

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:

Pterosaurs date just after the 240 million split from dinosaurs common ancestor, or so they say.

Which split, and why is it relevant ? And “just after” is millions of years.

quote:

I would say that Pterosaurs and birds might have had a common ancestor back around 275 million to 300 million years ago then split (say 270 million years ago). Birds might have split around 250 million years from theropods

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.


This message is a reply to:
 Message 29 by LamarkNewAge, posted 01-29-2018 8:11 AM LamarkNewAge has responded

Replies to this message:
 Message 35 by LamarkNewAge, posted 01-29-2018 7:30 PM PaulK has not yet responded

    
caffeine
Member
Posts: 1559
From: Prague, Czech Republic
Joined: 10-22-2008
Member Rating: 4.0


Message 32 of 62 (827681)
01-29-2018 1:48 PM
Reply to: Message 19 by LamarkNewAge
01-28-2018 10:11 AM


Re: Caffeine
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:
(...)What makes the discovery especially surprising and puzzling is that the heart resembles a mammal's or bird's but it belonged to an ornithischian, or bird-hipped, dinosaur, one of the two main lineages of these great reptiles. Despite the name, these dinosaurs were far removed from those that were presumed by many paleontologists to have been ancestors of birds; these ancestors were presumed to be theropods, members of the other main lineage known as the saurischian, or lizard-hipped, dinosaurs.(...)

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.


This message is a reply to:
 Message 19 by LamarkNewAge, posted 01-28-2018 10:11 AM LamarkNewAge has responded

Replies to this message:
 Message 34 by LamarkNewAge, posted 01-29-2018 6:09 PM caffeine has responded

  
caffeine
Member
Posts: 1559
From: Prague, Czech Republic
Joined: 10-22-2008
Member Rating: 4.0


(1)
Message 33 of 62 (827686)
01-29-2018 2:14 PM
Reply to: Message 29 by LamarkNewAge
01-29-2018 8:11 AM


Re: PaulK on the run. Won't respond to 2014 journal (nobody will).
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.


This message is a reply to:
 Message 29 by LamarkNewAge, posted 01-29-2018 8:11 AM LamarkNewAge has responded

Replies to this message:
 Message 36 by LamarkNewAge, posted 01-29-2018 9:19 PM caffeine has not yet responded

  
LamarkNewAge
Member
Posts: 1290
Joined: 12-22-2015


Message 34 of 62 (827695)
01-29-2018 6:09 PM
Reply to: Message 32 by caffeine
01-29-2018 1:48 PM


Since 99% of what I say gets ignored (especially by PaulK):might have to be selective
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:

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.


It works both ways, huh?

caffeine states:

quote:

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.


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:

Modern Birds Existed Before Dinosaur Die-Off

Sara Goudarzi
for National Geographic News

February 8, 2008

Modern birds originated a hundred million years ago—long before the demise of dinosaurs, according to new research.

In searching for the first ancestors of modern birds, studies have shown discrepancies between results from fossils and genetic analyses.

Fossil records suggest that modern birds originated 60 million years ago, after the end of the Cretaceous period about 65 million years ago when dinosaurs died off.

But molecular studies suggest that the genetic divergences between many lineages of birds occurred during the Cretaceous period.

Now a new study based on molecular evidence suggests that avian ancestors were flapping their wings some 40 million years earlier than thought.

In the new study researchers applied a new method of research that looks at mutation rates across lineages.

"My goal for this study was to once and for all reconcile divergence estimates from these two sources of information," said lead study author Joseph Brown, a graduate student at the University of Michigan in Ann Arbor.

The study appeared recently in the journal BMC Biology.

When dating biological events, molecular geneticists rely on a concept known as the molecular clock.

Over long stretches of time, mutations accrue, or "tick," at a fairly constant rate. By measuring the degree of genetic mutations, scientists can estimate how far back in time a species diverged.

In large groups of distantly related species—such as different families or orders of birds—the molecular clock is much "sloppier" than previously thought, Brown said.

This is because different lineages of birds can accumulate mutations at different rates, so applying a single rate to an entire family tree could lead to suspicious results.

Estimates

The study is the first rigorous investigation into whether bad assumptions about birds' genetic data have led to the large difference—about 50 to 60 million years—between fossil- and genetic-based estimates, researchers say.

The most likely explanation is that these two sources of information deal with different stages of diversification.

Genetic data is used for the period when genes share a common ancestor, which could slightly predate the development of new species. Fossils, however, record only the products of evolution.

https://news.nationalgeographic.com/...208-bird-origins.html


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:

Feduccia and like-minded peers have been provided no solid alternate hypotheses about where, when, why and how birds originated—they point to some yet-unknown lineage of creatures that might have lived more than 200 million years ago—but they insist that birds cannot be dinosaurs. Yet Feduccia’s argument in his new book Riddle of the Feathered Dragons is not quite that simple.

....

Perhaps more importantly, however, there is no indication that creatures such as Oviraptor and Velociraptor were birds. Analysis after analysis has found them to be unequivocal, non-avian dinosaurs within the coelurosaur subgroup. Although Feduccia hypothesizes that birds originated from some mysterious Triassic ancestor, and then bird-like dinosaurs evolved from early birds, there is not a shred of evidence that such an evolutionary repeat ever took place. The idea is an attempt to remove uncomfortable facts in the way of a preconceived view.

....

Ultimately, though, many of Feduccia’s objections boil down to a rejection of a methodology known as cladistics. This method of determining relationships among organisms is based on the analysis of shared derived characteristics—specialized features found in two organisms or lineages and their most recent common ancestor. Researchers look for numerous traits, record whether the traits in question are present or absent, and then insert that mass of data into a computer program that produces a hypothesis about the relationships among the various organisms included in the study. The point is not to find direct ancestors and descendants, but to figure out who is most closely related to whom. The method is not perfect—which organisms are included, the choice of traits for comparison and the way those traits are scored all affect the outcome. Still, this process has the benefit of requiring researchers to show their work. Each evolutionary tree resulting from such methods is a hypothesis that will be tested according to new evidence and analyses. If someone disagrees with a particular result, they can sift through the collected data to see if an inappropriate trait was included, an essential organism was left out, or if there was some other problem. Cladistics is useful not because it results in a perfect reflection of nature each time, but because it allows researchers to effectively examine, test and improve ideas about relationships.

https://www.smithsonianmag.com/...84209/#lQy1QFxw7FFcAYlB.99


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:

COMMENT ON THE DEFINITION OF AVES:
Gauthier (1986) applied a crown-group definition
to Aves, which consists of the last common
ancestor of Ratiti, Tinami, and Neognathae
and all of its descendants. This restricted the
name Aves to the least inclusive monophyletic
group containing all living birds. This definition
excluded Archaeopteryx lithographica
and numerous fossil taxa commonly referred
to as ‘‘birds’’ from Aves. These taxa and Aves
proper are subsumed by the more inclusive
stem-based lineage Avialae, which Gauthier
(1986) coined to encompass fossil taxa historically
thought to be birds because of the
presence of feathers and presumed flight
abilities. However, nearly every single character
that at one time was thought to make
something a ‘‘bird’’ is now known to occur
progressively earlier in theropod evolution.
Therefore, ‘‘bird’’ is a colloquial term that
lacks a meaningful taxonomic or scientific
basis as it has no precise phylogenetic meaning.

Birds are being found earlier.

It is recognized that they are difficult to find.

quote:

It was in 1995 that Zhou and colleagues announced the discovery of a fossil from this prehistoric disaster zone that heralded a new age of paleontology. The fossil was a primitive bird the size of a crow that may have been asphyxiated by volcanic fumes as it wheeled above the lakes all those millions of years ago. They named the new species Confuciusornis, after the Chinese philosopher.

Until then, only a handful of prehistoric bird fossils had been unearthed anywhere in the world. That’s partly because birds, then as now, were far less common than fish and invertebrates, and partly because birds more readily evaded mudslides, tar pits, volcanic eruptions and other geological phenomena that captured animals and preserved traces of them for the ages. Scientists have located only ten intact fossilized skeletons of the earliest known bird, Archaeopteryx, which lived at the end of the Jurassic period, about 145 million years ago.

Read more: https://www.smithsonianmag.com/...57706/#a4vJTchp0CC27RMI.99


And I note that the 13 pre Theropoda features in Scansoriopteryx are still being ignored.


This message is a reply to:
 Message 32 by caffeine, posted 01-29-2018 1:48 PM caffeine has responded

Replies to this message:
 Message 37 by PaulK, posted 01-30-2018 12:31 AM LamarkNewAge has responded
 Message 47 by caffeine, posted 02-01-2018 2:22 PM LamarkNewAge has responded

    
LamarkNewAge
Member
Posts: 1290
Joined: 12-22-2015


Message 35 of 62 (827696)
01-29-2018 7:30 PM
Reply to: Message 31 by PaulK
01-29-2018 1:23 PM


Re: LamarckNewAge resorts to pretending responses don’t exist
quote:

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.

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:

Avian origins: new analysis confirms ancient beginnings
Feb 15, 2008
Contact Nancy Ross-Flanigan

ANN ARBOR, Mich.—Did modern birds originate around the time of the dinosaurs' demise, or have they been around far longer?

The question is at the center of a sometimes contentious "rocks versus clocks" debate between paleontologists, whose estimates are based on the fossil record, and scientists who use "molecular clock" methods to study evolutionary history.

A new analysis by researchers at the University of Michigan, the University of Chicago, the Centre for Biodiversity Conservation Mexico and Central America, and Boston University offers the strongest molecular evidence yet for an ancient origin of modern birds, suggesting that they arose more than 100 million years ago, not 60 million years ago, as fossils suggest.

The research was published online Jan. 28 in the journal BMC Biology.

"Scientists typically use two sources of information to date biological events: the fossil record, which contains physical remains of ancient organisms, and molecular genetic data," said graduate student Joseph Brown, who is first author on the paper. In the case of modern birds, however, the two approaches have yielded conflicting results, at times leading to heated debates between paleontologists and molecular biologists. Molecular biologists have asserted that the fossil record must be incomplete, while paleontologists have countered that the genetic data must be suspect.

In fact, both approaches have their weaknesses, Brown said. Fossils tend to underestimate how much time has passed since lineages diverged. That's because fossils preserve only evidence of changes in outward physical appearance, and such changes take some time to accumulate after the actual "speciation event" that marks the divergence.

As for genetic data, the so-called molecular clock isn't quite as precise as once thought. The approach relies on the observation that although mutations occur at random in the genome, when looked at over long stretches of time they occur (or "tick") at a fairly constant rate. Molecular biologists use that rate to reconstruct evolutionary history.

"If we know, for example, that DNA sequences diverge by an average of two percent every million years, and we determine that two species differ genetically by ten percent, we can figure out that they last shared a common ancestor five million years ago," Brown said. The problem is, "different lineages can 'tick' at different rates, so applying a single rate to an entire tree could lead to very suspect results."

Fortunately, new methods exist for compensating for differing rates.

"What my colleagues and I did was apply all of these new methods to the problem of the origin of modern birds, with each method making different assumptions about how mutation rate changes across the tree," Brown said. He hoped the analysis would narrow the gap between fossil and molecular data, but in fact it only reinforced the rock-clock split by underscoring the finding that modern birds arose more than 100 million years ago.

So where does that leave the contentious camps of scientists trying to solve the puzzle of how the world's 10,000 bird species came about?

"Rather than fighting across groups, we now have the joint goal of explaining this rock-clock gap," Brown said. "Resolution of the issue will be fertile ground for future research for a while to come."

Brown's coauthors on the paper are Joshua Rest of the University of Chicago, Jaime Garc

http://ns.umich.edu/...-analysis-confirms-ancient-beginnings


Birds existed more than 40 million years earlier than the fossils.

You said:

quote:

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.

o.k.

Here is Wikipedia:

quote:

A few fossil traces tentatively associated with the Coelurosauria date back as far as the late Triassic. What has been found between then and the start of the late Jurassic is fragmentary. A typical example is Iliosuchus, known only from two ilia bones in the mid Jurassic. It was a 1.5 m long carnivore from about 165 Ma (million years ago) in Oxfordshire and is tentatively assigned to the Tyrannosauroidea.

So 165 million plus 40 would be at least 205 million.

Then you said.

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.

https://en.wikipedia.org/wiki/Scansoriopteryx

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:

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.

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!).


This message is a reply to:
 Message 31 by PaulK, posted 01-29-2018 1:23 PM PaulK has not yet responded

    
LamarkNewAge
Member
Posts: 1290
Joined: 12-22-2015


Message 36 of 62 (827697)
01-29-2018 9:19 PM
Reply to: Message 33 by caffeine
01-29-2018 2:14 PM


Change title to hope for issues getting addressed.
quote:

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.


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:

Speciation normally occurs in geographic isolation, but the distributions of birds are complicated and ever changing. Populations once isolated often come into contact, and when they do, the amount, duration, and results of hybridization will vary from instance to instance.

Something on the order of 10 percent of North American birds that are considered specifically distinct hybridize with other species.

https://web.stanford.edu/...s/text/essays/Hybridization.html


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:

AN ARBOREAL
MANIRAPTORAN FROM
NORTHEAST CHINA
STEPHEN A. CZERKAS and CHONGXI YUAN
The Dinosaur Museum, 754 South 200 West, Blanding, Utah 84511, USA;
Institute of Geology, Chinese Academy of Geological Sciences,
Baiwanzhuang Road 26,
Beijing 100037, People’s Republic of China.
....
Furthermore, the application of cladistics, or
phylogenetic analysis, has generated a broad
consensus in accepting birds as being derived from
theropod dinosaurs, notably from within the
Maniraptora (Gauthier, 1986).

....

Scansoriopteryx heilmanni is the only known
saurischian, or theropod, which has the third digit
of the manus elongated to nearly twice that of the
second digit. Scansoriopteryx closely resembles
Archaeopteryx, but differs in the following: a
definite contact between an elongate ventral process
of the postorbital and the ascending process of the
jugal; the lower jaw is equipped with a large
fenestra; the tail has a greater development in the
articulation of the zygapophyses. The pelvis is
similar to that of Archaeopteryx in having the same
number of sacrals and general shape of the ilia, but
differs in having a small, unexpanded pubic
peduncle; a significantly short pubis which is not
retroverted; longer ischia; and an acetabulum which
is not entirely perforated. Also unlike
Archaeopteryx, the posterior end of the scapula is
expanded; separate clavicles are present instead of
a furcula; and the foot is more capable of perching
as indicated by its having a longer hallux, and the
reduced lengths of the middle phalanges in digits
III and IV of the pes.

....

In April, 2000, at the Florida Symposium
on Dinosaur/Bird Evolution presented by the
Graves Museum of Archaeology and Natural
History, the fossil of Scansoriopteryx was initially
presented as an “arboreal theropod”. However, this
terminology is an apparent contradiction in terms
as according to definition, “theropods” do not
climb. Also, according to Gauthier (1986),
theropods are united as a group by having the
second digit of the manus as being the longest. Since
the third digit in the manus of Scansoriopteryx is
much longer than the second, it must either
represent a highly derived specialization from that
of typical theropods, or must represent a
pre-theropod status. The combination of the third

digit having a more elongate and robust third
metacarpal; together with phalanges that become
progressively shorter distally, as well as the
numerous primitive characteristics throughout the
body collectively suggest that these are not aberrant
reversals but reflect true plesiomorphic conditions.
Therefore, Scansoriopteryx is more parsimoniously
regarded as being a saurischian of “pre-theropod”
status, instead of as a true theropod.
While Archaeopteryx has remained the most
primitive, basal bird known to Science for the past
140 years, there has been considerable debate and
at times heated controversies as to what the
precursor of Archaeopteryx was like and how the
evolution of avian flight began. Scansoriopteryx
most closely resembles Archaeopteryx in its number
of caudal vertebrae, basic structure of the tail, sacral
vertebrae, shape of the ilia, the length of forelimb,
and general morphology of the skull. The most
significant differences between the two animals are
characters which would ordinarily be considered
as primitive.


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:

Hybridization, the interbreeding of species, provides favorable conditions for major and rapid evolution to occur. In birds it is widespread. Approximately one in ten species is known to hybridize, and the true global incidence is likely to be much higher

http://science.sciencemag.org/content/256/5054/193


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:

You can then entertain yourself looking through the 51 shared characters in their matrix that support scansoriopterygids as paravians.

"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: 14563
Joined: 01-10-2003
Member Rating: 2.1


Message 37 of 62 (827698)
01-30-2018 12:31 AM
Reply to: Message 34 by LamarkNewAge
01-29-2018 6:09 PM


Pretending that you are being ignored won”t work
quote:

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).

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:

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?


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:

A 50 to 60 million year discrepancy in just the last 100-125 million years!

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:

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.


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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Replies to this message:
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Pressie
Member
Posts: 1977
From: Pretoria, SA
Joined: 06-18-2010
Member Rating: 2.8


Message 38 of 62 (827701)
01-30-2018 6:32 AM
Reply to: Message 37 by PaulK
01-30-2018 12:31 AM


Lignin
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.


This message is a reply to:
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PaulK
Member
Posts: 14563
Joined: 01-10-2003
Member Rating: 2.1


(1)
Message 39 of 62 (827702)
01-30-2018 6:44 AM
Reply to: Message 38 by Pressie
01-30-2018 6:32 AM


Re: Lignin
Because the lignin argument was so obviously stupid that not even LNA can bring himself to try and defend it.
This message is a reply to:
 Message 38 by Pressie, posted 01-30-2018 6:32 AM Pressie has responded

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Pressie
Member
Posts: 1977
From: Pretoria, SA
Joined: 06-18-2010
Member Rating: 2.8


Message 40 of 62 (827704)
01-30-2018 7:08 AM
Reply to: Message 39 by PaulK
01-30-2018 6:44 AM


Re: Lignin
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: 1290
Joined: 12-22-2015


Message 41 of 62 (827766)
01-31-2018 5:43 PM
Reply to: Message 37 by PaulK
01-30-2018 12:31 AM


Birds, Reptiles, Frogs, and evolution with hybridization.
I said:
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.


PaulK said:

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.

I put this search term into www.google.com:

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:

Evolution 58(8):1865-1870. 2004
https://doi.org/10.1554/04-190

RATES OF EVOLUTION OF HYBRID INVIABILITY IN BIRDS AND MAMMALS

No Access

Benjamin M. Fitzpatrick
M. Nachman

The Society for the Study of Evolution
Received: March 22, 2004; Accepted: April 16, 2004

[+] Author & Article Info

Abstract

Almost 30 years ago, A. C. Wilson and colleagues presented results indicating that hybrid inviability between species evolves 10 times faster in mammals than in birds and frogs. Here I revisit this question for birds and mammals using modern molecular data (mitochondrial cytochrome b DNA) and a more phylogenetically appropriate statistical approach. My analyses confirm that diverging mammals lose the ability to form viable hybrids faster than birds. To explain the difference in rates of evolutionary loss of hybridization potential, Wilson and coworkers proposed that mammals have higher rates of regulatory evolution, causing higher probabilities of developmental incompatibilities between mammal species. I briefly discuss this and other potential explanations.

http://www.bioone.org/doi/abs/10.1554/04-190


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 http://science.sciencemag.org/content/256/5054/193 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.

http://www.dailymail.co.uk/...-evolution-unusually-slow.html

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:

Pterosaurs to Birds: Scansoriopteryx
pterosaurnet.blogspot.com/2014/07/scansoriopteryx.html

Jul 25, 2014 - The re-examination of a sparrow-sized fossil [Scansoriopteryx] from China challenges the commonly held belief that birds evolved from ground-dwelling theropod dinosaurs that gained the ability to fly. The birdlike fossil is actually not a dinosaur, as previously thought, but much rather the remains of a tiny ...


It is good to get the important things right.

Scansoriopteryx is important.

And it is something that can't be ignored.


This message is a reply to:
 Message 37 by PaulK, posted 01-30-2018 12:31 AM PaulK has responded

Replies to this message:
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LamarkNewAge
Member
Posts: 1290
Joined: 12-22-2015


Message 42 of 62 (827767)
01-31-2018 6:53 PM
Reply to: Message 37 by PaulK
01-30-2018 12:31 AM


Re: Pretending that you are being ignored won”t work
quote:

Feduccia et al propose that birds were successful enough to produce quite a range of theropod descendants - which turn up before birds!

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.

www.google.com

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 Ornithology
October 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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 Message 37 by PaulK, posted 01-30-2018 12:31 AM PaulK has responded

Replies to this message:
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PaulK
Member
Posts: 14563
Joined: 01-10-2003
Member Rating: 2.1


Message 43 of 62 (827774)
02-01-2018 12:04 AM
Reply to: Message 42 by LamarkNewAge
01-31-2018 6:53 PM


Re: Pretending that you are being ignored won”t work
quote:

I am not so sure he says that, but it sounds like something close to what I said

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:

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).


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:

It has lots of references (and critical reviews? it seems so) to the recent journal by (the late) Czerkas and Feduccia

Most of what that search finds is either of little or no relevance. (“Springer’s Journal” crops up quite a bit)

quote:

Understand that Feduccia is often attacked over OLD stuff like the digit 1-2-3- and 2-3-4 issue.

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:

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.

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: 14563
Joined: 01-10-2003
Member Rating: 2.1


Message 44 of 62 (827775)
02-01-2018 12:16 AM
Reply to: Message 41 by LamarkNewAge
01-31-2018 5:43 PM


Re: Birds, Reptiles, Frogs, and evolution with hybridization.
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:

It is good to get the important things right.

Then I hope you will start trying.

quote:

Scansoriopteryx is important.

And it is something that can't be ignored


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.


This message is a reply to:
 Message 41 by LamarkNewAge, posted 01-31-2018 5:43 PM LamarkNewAge has responded

Replies to this message:
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LamarkNewAge
Member
Posts: 1290
Joined: 12-22-2015


Message 45 of 62 (827805)
02-01-2018 1:57 PM
Reply to: Message 44 by PaulK
02-01-2018 12:16 AM


Re: Birds, Reptiles, Frogs, and evolution with hybridization.
quote:

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.

Start with this:

mammals average 2-4 million years.

quote:

Mammalian rates of evolution of hybrid inviability are considerably faster than other vertebrates, but still average 2-4 million years ( Fitzpatrick 2004

https://www.researchgate.net/...mmals_Evolution_58_1865-1870


I put "mammals post-zygotic isolation. years" into www.google.com 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:

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.

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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 Message 44 by PaulK, posted 02-01-2018 12:16 AM PaulK has responded

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