Feathers, huh? I have my doubts

[CarnegieCollector]

Hi everyone! I hope your having a jolly day! 

I have been readin' up on "feathered" dinosaurs, and I am sorta doubtful. I'll give my reasons below!

Disclaimer!: I DO believe dinosaurs such as the oviraptorids had feathers, and many other dinosaurs could also have had them. I am simply doubtful over the other claims of feathers on dinosaurs. I mean all this in a nice, sincere way, and I don't wanna cause any arguments or war (or bloodshed).

During my reading on feathered dinosaurs, I looked at many pictures of the fossil imprints. These include beipiosaurus, Yutyrannus, sinosauropteryx, etc. and I realized that these "feather" imprints don't resemble feathers in any way. True feathers are semi-hollow shafts that grow out of skin follicles, like hair. True feathers are very complex, having many barbs, extensions, hooks, and the like. None of the structures found on the dinosaurs I mentioned have these. The structures found on said dinosaurs are too simple to be feathers. They're more like mammalian fur. And we all know reptiles can (and did!) have simple fur. I'm looking at you pterosaurs. The "fuzz" found on these dinosaurs more closly resembles the pycnofibres found on pterosaurs than true feathers.

The more bird-like dinosaurs with DEFINATE, TRUE, WITHOUT A SHADOW OF A DOUBT feathers, seem to resemble birds. Not dinosaurs.....but true birds. Archaeopteryx is now considered a true bird, as well as confusiosornis. Many of the features found on these two birds are shared with other extinct birds. Hesporornis had teeth, some of the giant "terror birds" had claws on their wings (some modern day birds such as emus, ostriches, and hoatzin chicks also have claws), and birds such as roadrunners are only capable of gliding and flying short distances, something that archaeopteryx seems capable of doing. Microraptor, protoavis, and other "dinosaurs" seem to resemble these true birds more than they do dinosaurs. Who's to say these feathered critters aren't true birds either? As for other feathered bird-like dinosaurs......I don't know....
Zhenyaunlong, caudipteryx, and protarcheopteryx could vary well be feathered dinosaurs, but caudipteryx and protarcheopteryx (in my opinion) are more likely flightless birds. I don't know what to think of zhenyaunlong.


Some dinosaurs such as apatoraptor, struthiomimus, velociraptor, dakotaraptor, and concavenator, have all been found with small bumps on their fore-arms. These are always interpreted as quil knobs, something birds possess, to hold the primary feathers on the arms. But these could also simply be the result of deterioration, erosion, or anchor points for muscles. I'm not saying they're NOT quil knobs, but they could be a number of other things.

Thank you for reading my (most likely very stupid) post! Have a nice day!

Like I said before, I do indeed believe some dinosaurs had feathers, and I Definatly believe some dinosaurs had a pycnofiber like fur on them.

 

[Concavenator]

 Years ago,it was revealed that any dinosaur had the possibility of having feathers.But,even though not every dinosaur possibly had feathers,there were still a large amount of feathered dinosaurs.Dromeosaurs,troodontids,therizinosaurids,ornithomimids and tyrannosaurs were definetely feathered,at least from what fossils proof.And at least some small ornisthischians like Tianyulong and Kulindadromeus had feathers as well.

[Silvanusaurus]

This could get hairy... 

[CarnegieCollector]

This could get hairy... 

oh my gosh! Lol!

[Brontozaurus]

You're talking about primitive feathers. "True" feathers in the modern sense didn't spring into existence in their current shape but evolved from the simple structures you described. We know this not only from fossils, but from embryological studies of modern birds. And yes, primitive feathers and pterosaur pycnofibres look similar but aren't structurally the same, otherwise we'd be using the same term for both of them.

As far as quill knobs go, we're certain that they're present on the dromaeosaurids you mentioned because every dromaeosaurid fossil preserving integument has primary feathers arranged on the arms like modern birds do, so by the logic of phylogenetic bracketing it makes sense that these structures were quill knobs. Ornithomimus is similar, with evidence of feathers on the arms suggesting that the structures were quill knobs. Concavenator is more controversial cause we have no evidence for complex feathers in its immediate family, though it seems that it's now agreed that the 'quill knobs' were actually muscle attachment points.

[suspsy]

Passionate post there, CarnegieCollector. Now my question for you is: where is your actual evidence?

I mean, yes, you've stated that you looked at a bunch of pictures and to you, some of those feather impressions don't look like the"true  feathers" you see on eagles or storks or gulls or whichever. And you claim that the quill knobs on Dakotaraptor look like the result of erosion, IYO. But again, where is your actual evidence for this claim? Where is your study? Your diagrams? Your sources? What makes your argument stronger than that of dozens of paleontologists who have been studying dinosaurs for decades and have examined all of these fossils in person?

And don't make the mistake that only "true feathers," as you called them, count as feathers. There are Type 1 feathers that are simple, hollow pointed shafts. Type 2 feathers which are down with no vanes (Sinosauropteryx). Type 3 feathers that have vanes and shafts, but no barbules holding them together (Beipiaosaurus, Velociraptor, Yutyrannus, Tyrannosaurus rex). Type 4 feathers that have barbules linking the vanes into a continuous surface with the shaft in the very centre (Caudipteryx). And finally, Type 5 feathers where the shaft is near the leading edge of the vane which allow for proper flight (Archaeopteryx). And no one can arbitrarily dismiss any of these types simply because it suits their anti-feathered argument.

[Halichoeres]

Hi, CarnegieCollector--

The main reason that we're so sure about the widespread presence of feathers among, at least, coelurosaurian dinosaurs, is phylogenetic bracketing, as Brontozaurus alluded to. Phylogenetic bracketing is a type of character optimization, which means using the family tree of organisms to deduce how and where any trait of interest evolved. For example: we know that animals like Euryzygoma and Thylacoleo had pouches, even though the fossils don't preserve that feature directly. There's some indirect physical evidence, like the presence of epipubic bones, but epipubic bones probably had other functions, so we can't be sure from that alone. A stronger argument by far is our knowledge that Euryzygoma is more closely related to kangaroos and koalas than to opossums. Now, opossums, koalas, and kangaroos all have pouches, so if we wanted to say that Euryzygoma didn't have one, we'd have to think of some reason it should have lost it.

It's similar with coelurosaurian dinosaurs. We have direct evidence from Archaeopteryx, from Dilong, from Beipiaosaurus, and from Struthiomimus. Given what we know about their relationships (they circumscribe a lineage that includes Tyrannosaurus, Velociraptor, etc), we have to assume that the simple feathers, at least, were fairly widespread.

Finally, Archaeopteryx is often called the first bird, but it's called that because of tradition, not because it's especially birdlike. It lived least 50 million years before the most recent common ancestor of all modern birds. It's just one of many dinosaurs that were on the bushy, bushy lineage leading to birds, and it happens to have been preserved in a way that shows its feathers. It would be asking too much of the fossil record to require it to preserve feathers often--they are simply too fragile for anything other than an anoxic lagoon to save them in detail. Some feather impressions from less favorable sites probably represent decay of the feathers, rather than actual simplicity.

[stargatedalek]

While there is a small amount of semantic "wiggle room" terms like "proto-feather" or "dino-fuzz" are still best considered as misnomers as they lead to inevitable confusion and false impressions (as has so clearly occurred here). The fact of the matter is that beyond a doubt these filaments are ancestral to "current feathers", whether you call them feathers or not doesn't necessarily matter, but it's better to call them feathers to prevent confusion and even deliberate misuse (it's happened). Plus if you look at downy feathers, or the less developed feathers of some infant birds the structure is similar to animals like Yutyrannus, so these still fit within the realm of what can be called "current/true feathers" regardless.

Quill knobs are quill knobs, the fossils you mention are clear enough to identify these are not preservation artifacts, nor would the region of the arm have any other purpose to possess such muscle attachments. The shafts themselves don't reach the bone, rather the quill knobs support a specialized muscle that supports the shafts. The idea of it being another muscle attachment has already been tested to death with Concavenator*, and in the end the result was the same as Velociraptor and Dakotaraptor. Feathers make a hell of a lot more sense than a literally pointless (and rather large) muscle.

* It was still considered another muscle until fairly recently. And some people argue that Concavenators quill knobs represent literal "quills" like a lionfish, but I think it's far more reasonable to stick with the most likely explanation than to invent an entirely new theoretical integument just to isolate feathers within coelurosauria.

[Megalosaurus]

CarnegieCollector:
I understand most of your arguments and opinions, as I myself had readed a lot of papers of dinosaurs with preserved integument. (I'm not a paleontologist, so I don't pretend to know more than any forum member).
You may find extensive threads* in this forum discusing that subject, where you may find objective arguments, but also conjetural ones, and some very "passionate" ones defending one or another posture.
What I want to do is to thank you for sharing your point of view. Please keep questioning and researching, never just accept the crowd's opinion.
As for me, I go with direct evidence as much as possible.

So this is my Tyrannosaurus:


But this is my Sinosauropteryx:


This is my Triceratops:


But this is my Microraptor:


This is my Edmontosaurus:


And so on.

Cheers.

*
http://dinotoyblog.com/forum/index.php?topic=1742.0
http://dinotoyblog.com/forum/index.php?topic=1804.0
http://dinotoyblog.com/forum/index.php?topic=3575.0

[CarnegieCollector]

Passionate post there, CarnegieCollector. Now my question for you is: where is your actual evidence?

I mean, yes, you've stated that you looked at a bunch of pictures and to you, some of those feather impressions don't look like the"true  feathers" you see on eagles or storks or gulls or whichever. And you claim that the quill knobs on Dakotaraptor look like the result of erosion, IYO. But again, where is your actual evidence for this claim? Where is your study? Your diagrams? Your sources? What makes your argument stronger than that of dozens of paleontologists who have been studying dinosaurs for decades and have examined all of these fossils in person?

And don't make the mistake that only "true feathers," as you called them, count as feathers. There are Type 1 feathers that are simple, hollow pointed shafts. Type 2 feathers which are down with no vanes (Sinosauropteryx). Type 3 feathers that have vanes and shafts, but no barbules holding them together (Beipiaosaurus, Velociraptor, Yutyrannus, Tyrannosaurus rex). Type 4 feathers that have barbules linking the vanes into a continuous surface with the shaft in the very centre (Caudipteryx). And finally, Type 5 feathers where the shaft is near the leading edge of the vane which allow for proper flight (Archaeopteryx). And no one can arbitrarily dismiss any of these types simply because it suits their anti-feathered argument.

Well, I didn't make any diagrams, extensive studies, and I haven't dedicated my life to studying these fossils in person....I am simply making observations. I didn't read anything about the "type" feathers, so I know little about them.
As far as my "evidence" goes, I really wanted to attach some photos, but I don't know how to, other than copying and pasting, which would take a rather long time.
I will, for the heck of it, attach a fossilized feather imprint compared to a floofy dinosaurs "feather" imprints.
I don't wanna sound weird or anything but, how do we know these "type feathers" are feathers at all? Stupid question, I know. We know many, many types of animal covering exists, so how do we know these aren't a unique structure?

[suspsy]

Well, I didn't make any diagrams, extensive studies, and I haven't dedicated my life to studying these fossils in person....I am simply making observations. I didn't read anything about the "type" feathers, so I know little about them.

Well, not to sound harsh, but if you don't know about the different types of feathers, you're in no position to argue that certain fossils actually aren't feathered at all. 

As far as my "evidence" goes, I really wanted to attach some photos, but I don't know how to, other than copying and pasting, which would take a rather long time.
I will, for the heck of it, attach a fossilized feather imprint compared to a floofy dinosaurs "feather" imprints.

That first photo is an example of a Type 5 feather and that second one is an example of a type 2 or 3. This isn't evidence to support your argument.

I don't wanna sound weird or anything but, how do we know these "type feathers" are feathers at all? Stupid question, I know. We know many, many types of animal covering exists, so how do we know these aren't a unique structure?

Because paleontologists have been carefully studying these fossils for decades. Indeed, some have devoted their entire careers toward studying feathered dinosaurs. And their research goes far, far beyond looking at random photos on Google.

I would suggest that you heed what Halichoeres and Stargatedalek wrote. And read up more on feathering. This is but one good source:

http://people.eku.edu/ritchisong/feather_evolution.htm

[CarnegieCollector]

Oh well, I give up!  it was a stupid argument to begin with I guess.

It was an honor getting to talk with people much smarter about dinosaurs/feathers than I.
Thank you all for your replies! Have a grand day!

[suspsy]

There's nothing stupid about your post provided you have learned from what other people have shared with you.

[HD-man]

And at least some small ornisthischians like Tianyulong and Kulindadromeus had feathers as well.

At best, it's possible but not definite ("Note that the fuzz of the heterodontosaurid Tianyulong is very similar and some of the structures on Kulindadromeus are as well...Whether these turn out to be formed by convergence with theropods or retention in both groups of some ancestral dino-fuzz is not yet certain": https://www.geol.umd.edu/~tholtz/G104/lectures/104aves.html ) ("These appear similar to those integumental structures as in Tianyulong confuciusi...But what these are and what they might be related to is the subject of debate": https://qilong.wordpress.com/2016/01/24/a-brief-moment-in-kulinda/ ). At worst, they probably didn't (See the 1st post: http://dinotoyblog.com/forum/index.php?topic=3476.0 ).

Type 3 feathers that have vanes and shafts, but no barbules holding them together (Beipiaosaurus, Velociraptor, Yutyrannus, Tyrannosaurus rex).

Seems weird to use Velociraptor & T.rex as examples of stage 3 feathers given that 1) neither has been found preserved w/feathers, 2) Velociraptor had at least stage 4 feathers, & 3) we don't know for sure whether tyrannosaurids had feathers &, if so, to what extent.

[suspsy]

That's where phylogenetic bracketing comes into play.

[CarnegieCollector]

That's where phylogenetic bracketing comes into play.

Why do I picture phylogenetic bracketing laughing an evil laugh as it covers all coelurosaurians in Dino-fuzz and feathers?

[Postosuchus84]

What I want to do is to thank you for sharing your point of view. Please keep questioning and researching, never just accept the crowd's opinion.

Very eloquently put. I'm an amateur myself when it comes to Paleontology, I have been interested in it for a long time and science overall. It's a happy place for me. Science feels are the best feels actually.. I can't tell you how important it is to question and research curiosities about the world and see how they all work. The other thing is to remain open about things as much as possible and that's especially true as a citizen scientist as well as professional scientist.

On topic: Personally, I stand in the crowd that prefers copious to overwhelming amounts of evidence, but the odds of fossilization and all that is genuinely a "happy accident" when it does occur. Odds for fossilization and overall preservation is so ridiculous high due to so many different variables in the environment you are unfortunately going to be hard-pressed to find evidence for every single case of feathers on non-avian dinosaurs. There's some compelling evidence for it though with numerous specimens about it (Wiki has a decent a paleontology section actually from what I've heard). Especially with the find of Kulindadromeus. That animal was an ornithischian dinosaur and more ancestral than say Tianyulong (a heterodontosaurid) and Psittacosaurus (a ceratopsian) and had some fluff. So relying on phylogenetic bracketing you can sort of see it was not just limited to saurichian dinosaurs, but ornithisichian dinosaurs. Not to mention the pycnofibers on pterosaurs, which were archosaurs themselves, points to degrees of integument in archosaur line altogether being ancestral to a point.

[stargatedalek]

That may be stretching the degree of what we can call a "feather", but again, semantics.

Personally I don't think all those forms of integument are directly synonymous, we know for certain soft integument was lost at least five times among archosaurs (ceratosauria, hadrosaurs, ceratopsians, sauropods, and crocodilians). So I think it makes just as much sense that it was lost and then reappeared several times as opposed to being lost several times.

[CarnegieCollector]

I never really considered the ornithischians very much. As far as kulindadromeus goes, it's erm, "structures" don't really resemble the feather types that Suspsy explained. Or maybe I'm being a nincompoop again! 

No, in my opinion, it's "decorations" in its back seem more like porcupine quills to me....

[Postosuchus84]

That may be stretching the degree of what we can call a "feather", but again, semantics. Personally I don't think all those forms of integument are directly synonymous, we know for certain soft integument was lost at least five times among archosaurs (ceratosauria, hadrosaurs, ceratopsians, sauropods, and crocodilians). So I think it makes just as much sense that it was lost and then reappeared several times as opposed to being lost several times.

A valid point and I do agree. I personally feel it needs more testing and analysis to conclusively say what these structures exactly are, but the general consensus at the moment put forth is "feathers" for the moment. I personally feel the structures have more in common with pycnofibers than feathers, but again that's speculation on my part and it's basically here say. Admittedly I also don't have the years of professional training or expertise to say exactly what is. My pycnofibers "diagnosis" is a loose thing I have going for it.

I never really considered the ornithischians very much. As far as kulindadromeus goes, it's erm, "structures" don't really resemble the feather types that Suspsy explained. Or maybe I'm being a nincompoop again! 

No, in my opinion, it's "decorations" in its back seem more like porcupine quills to me....

Also fair enough. I just was presenting what's known at the moment on the subject in any case.