First dinosaurs probably didn't have feathers

[Eldorado]

"Prof Paul Barrett, a dinosaur researcher at the Museum, has conducted an analysis of all the known specimens of dinosaur skin and mapped them onto evolutionary trees to see how they relate.

"The study was carried out with Nicolás Campione and David Evans and published as a contribution to a new book The Evolution of Feathers.

"'To date, most examples of dinosaur feathers have been found in the meat-eating dinosaurs, known as theropods, which is the group that also includes birds,' explains Paul. 'So that is not too much of a surprise.

"'But there's been speculation as to how far back feathers appear in meat-eating dinosaur evolution, and whether feathers might also have been seen in all other dinosaurs.'"

Full monty at UK Natural History Museum: Link

[acute]

Dinosaurs had feathers, none of them had feathers, old ones had feathers, young ones had feathers, early ones had feathers, later ones had feathers, gay ones had feathers.

 

Edited March 26, 2020 by acute

[zygote]

Interesting stuff. It never really occurred to me that there might be many more species of feathered dinosaurs yet to be discovered.

The only one I knew about was our friend the great Archaeopteryx (pictured).

 

[drakonwick]

It would be really interesting to see a massive T-Rex decked out in a colorful plume of feathers!

[Orphalesion]

The main point of this is the question of how early feathers developed, if they had been present in the earliest dinosaurs, then every type of dinosaur could have potentially been partially or fully covered in feathers. If this is correct and the feathers that modern, avian dinosaurs (birds) have only arose among the theropods then it's less likely that every group of dinosaurs had the potential for feathers or feather-like skin coverings.

39 minutes ago, drakonwick said:

It would be really interesting to see a massive T-Rex decked out in a colorful plume of feathers!

Well T-Rex is was a theropod (the group of dinosaurs that we know for sure had feathered members,including all the surviving ones) and  we do know that some close relatives of T-Rex were partially or fully covered in feather fuzz, but as far as I know we do not have any direct evidence of T-Rex feathers. So it's fair to assume that the T-Rex was at least partially covered in feathers, but we don't know for sure at this point. One argument against a fully feathered T-Rex is that it due to its size it might not have needed a full feather-covering to keep its body temperature intact and we do have some scaly skin impressions from parts of T-Rex's body, but that says nothing about partial feather coverings or things like crests or feathery "manes" like some modern birds of prey have.
Personally I prefer the more feathered reconstructions of T-Rex, but I've been a huge fan of feathery non-avian dinosaurs ever I read about them.

 

2 hours ago, zygote said:

Interesting stuff. It never really occurred to me that there might be many more species of feathered dinosaurs yet to be discovered.

The only one I knew about was our friend the great Archaeopteryx

Oh that's long outdated. By now we know, or have evidence of varying strength, of many, many of mesozoic theropod dinosaurs had full or partial feather coverings (and some from other groups who have evidence for feathers or feather-like structures). As the article writes, for a while it was assumed that it was an ancestral trait of all dinosaurs, with some losing them later in their evolution, but that might not have been the case after all.
But feathers were definitely a feature of mesozoic theropods.

[drakonwick]

On 3/27/2020 at 1:40 AM, Orphalesion said:

The main point of this is the question of how early feathers developed, if they had been present in the earliest dinosaurs, then every type of dinosaur could have potentially been partially or fully covered in feathers. If this is correct and the feathers that modern, avian dinosaurs (birds) have only arose among the theropods then it's less likely that every group of dinosaurs had the potential for feathers or feather-like skin coverings.

Well T-Rex is was a theropod (the group of dinosaurs that we know for sure had feathered members,including all the surviving ones) and  we do know that some close relatives of T-Rex were partially or fully covered in feather fuzz, but as far as I know we do not have any direct evidence of T-Rex feathers. So it's fair to assume that the T-Rex was at least partially covered in feathers, but we don't know for sure at this point. One argument against a fully feathered T-Rex is that it due to its size it might not have needed a full feather-covering to keep its body temperature intact and we do have some scaly skin impressions from parts of T-Rex's body, but that says nothing about partial feather coverings or things like crests or feathery "manes" like some modern birds of prey have.
Personally I prefer the more feathered reconstructions of T-Rex, but I've been a huge fan of feathery non-avian dinosaurs ever I read about them.

 

Personally, I liked the article and the subject in general! We know that feathered birds evolved from dinosaurs. But the question, when did some of these meat-eating dinosaurs evolve feathers...  I also find it interesting that one part of the article went into speculation, as it's been found that other herbivorous species of dinosaurs have been found to be covered in feather like structures.

Then it goes into the the definition of a what a "Feather" is!

It's all really interesting!

[Wepwawet]

I'm begining to think that the word feather should only be applied to maniraptors. To most people the word feather conjures up an image of the feathers we see on birds (maniraptors), so to describe a dinosaur such as Yutyranus or Kulindadromeus as having feathers, while scientifically correct, is misleading to the general public. What we see on non maniraptoran theropods and basal neornithiscians such as Kulindadromeus, should perhaps be referred to as hair, for better clarity in the appearance of an animal if nothing else.

As for the origins of dinosaur integument, then I'm convinced that we look at Ornithodira/Avemetarsalia, and that while there is convergent evolution within the descendants of that group, feathers/hair is basal to them all before they split into pterosaurs and dinosaurs.

[Carnoferox]

7 hours ago, Wepwawet said:

I'm begining to think that the word feather should only be applied to maniraptors. To most people the word feather conjures up an image of the feathers we see on birds (maniraptors), so to describe a dinosaur such as Yutyranus or Kulindadromeus as having feathers, while scientifically correct, is misleading to the general public. What we see on non maniraptoran theropods and basal neornithiscians such as Kulindadromeus, should perhaps be referred to as hair, for better clarity in the appearance of an animal if nothing else.

As for the origins of dinosaur integument, then I'm convinced that we look at Ornithodira/Avemetarsalia, and that while there is convergent evolution within the descendants of that group, feathers/hair is basal to them all before they split into pterosaurs and dinosaurs.

"Feather" should be restricted to branching filaments with barbs, in which case feathers would possibly be found in theropods as basal as allosauroids. The carcharodontosaurid Concavenator has potential quill knobs on its arms, which would indicate that it had pennaceous feathers similar to dromaeosaurids and modern birds. "Protofeather" or just "filament" would be the term for the non-branching forms seen on other dinosaurs. Using "hair" is misleading because these structures are not homologous to mammal hair/fur.

[Wepwawet]

On 3/27/2020 at 4:26 PM, Carnoferox said:

"Feather" should be restricted to branching filaments with barbs, in which case feathers would possibly be found in theropods as basal as allosauroids. The carcharodontosaurid Concavenator has potential quill knobs on its arms, which would indicate that it had pennaceous feathers similar to dromaeosaurids and modern birds. "Protofeather" or just "filament" would be the term for the non-branching forms seen on other dinosaurs. Using "hair" is misleading because these structures are not homologous to mammal hair/fur.

Well I wouldn't use the term "hair" to mislead of course, because a feather is a feather is a feather. It's just that when we see the term "feather" we, most of us I imagine, automatically think of the pennaceous feathers we see on a bird. So, if we saw a Yutyranus as they were, we might think of the description "hairy" more than "feathery". It's just a matter of perception from the perspective of the non specialist, not being strictly scientific.

 

I would like nothing better to have feathers confirmed for Concavenator, and any other theropod outside of Coelurosauria, and I'm 100% certain evidence will be found eventually, but I believe that so far no evidence has been found other than with Coelurosauria.

[Carnoferox]

8 hours ago, Wepwawet said:

I would like nothing better to have feathers confirmed for Concavenator, and any other theropod outside of Coelurosauria, and I'm 100% certain evidence will be found eventually, but I believe that so far no evidence has been found other than with Coelurosauria.

Besides the contentious quill knobs, Concavenator does provide indirect evidence of having a feathered ancestor. Concavenator has avian-type reticulate and scutate scales preserved on its feet, which are derived from pennaceous leg feathers.

https://www.researchgate.net/publication/275212425_Did_all_theropods_have_chicken-like_feet_First_evidence_of_a_non-avian_dinosaur_podotheca

https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1469-7580.2008.01041.x

[Wepwawet]

5 hours ago, Carnoferox said:

Besides the contentious quill knobs, Concavenator does provide indirect evidence of having a feathered ancestor. Concavenator has avian-type reticulate and scutate scales preserved on its feet, which are derived from pennaceous leg feathers.

https://www.researchgate.net/publication/275212425_Did_all_theropods_have_chicken-like_feet_First_evidence_of_a_non-avian_dinosaur_podotheca

https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1469-7580.2008.01041.x

So, digging around I come across Xing Xu of the IVPP writing that "Extensively feathered feet appear to be a plesiomorphic feature for Coelurosauria". I cannot give a link unfortunately. Allthough a specimen from Neotheropoda even remotely preserved like Sinosauropteryx has yet to be discovered, it's to much to imagine that Coelurosauria emerged fully covered in at least filaments from naked ancestors, and that will also hold true for Ceratosauria. I'm sure that all theropods were at least "hairy" to an extent, size dependent I would imagine, from when they first emerged.

I think the term "feather" is still an obstacle though in descriptive terms, for we have started from the position of only knowing that modern birds have feathers, with no idea whatsoever, Huxley and Archaeopteryx aside, that they were dinosaurs, so when the truth emerges, we end up using the term for an "end product" of evolution to describe it's beginnings, if you see what I mean, and putting the cart before the horse. But I'm being a bit pedantic about it I guess, and I know that if an Allosaurus were ever discovered to have just single filaments, which I'm sure it did, then it would be described as "fully feathered", with false images popping into peoples minds.

Edited April 18, 2020 by Wepwawet

[Carnoferox]

2 hours ago, Wepwawet said:

So, digging around I come across Xing Xu of the IVPP writing that "Extensively feathered feet appear to be a plesiomorphic feature for Coelurosauria". I cannot give a link unfortunately. Allthough a specimen from Neotheropoda even remotely preserved like Sinosauropteryx has yet to be discovered, it's to much to imagine that Coelurosauria emerged fully covered in at least filaments from naked ancestors, and that will also hold true for Ceratosauria. I'm sure that all theropods were at least "hairy" to an extent, size dependent I would imagine, from when they first emerged.

I think the term "feather" is still an obstacle though in descriptive terms, for we have started from the position of only knowing that modern birds have feathers, with no idea whatsoever, Huxley and Archaeopteryx aside, that they were dinosaurs, so when the truth emerges, we end up using the term for an "end product" of evolution to describe it's beginnings, if you see what I mean, and putting the cart before the horse. But I'm being a bit pedantic about it I guess, and I know that if an Allosaurus were ever discovered to have just single filaments, which I'm sure it did, then it would be described as "fully feathered", with false images popping into peoples minds.

Agreed, that's why I think the terms "filament" and/or "protofeather" should be used for non-branching filaments, with "feather" restricted to branching filaments.

[Tatetopa]

On 3/26/2020 at 5:37 PM, drakonwick said:

It would be really interesting to see a massive T-Rex decked out in a colorful plume of feathers!

Probably the last thoughts of a skink when a roadrunner shows up.  "Hmmm, that's interesting."