Tyrannosaurid skin impressions

[robintaylor]

It could always be a prehistoric case of the Montauk Monster.

A dead Tyrannosaurus get pulled out to sea where its carcass bloats and the primitive, hair-like feathers fall off. The body then washes back up onshore to be buried by the tide. Of course that gross speculation, but it could explain why the scales are apparently so strange as well as why some reports of Tyrannosaur impressions describe it as bare.

In all honesty, I don't really believe that though. If T. rex is scaly or feathered, it shouldn't matter. I never understood why people get so attached to a particular reconstruction, especially in a field of study filled with so much speculation. Its pretty much inevitable that the way we see dinosaurs will be changed in the future. Not too long ago we thought Spinosaurus was terrestrial and Deinocheirus was just a big ornithomimosaur for example. I get the nostalgia factor, but why is it so hard for people to separate the real animals from the outdated ideas of the 90s? The Jurassic Park T. rex is a fictionalized version of a real T. rex, like the ants from A Bug's Life or the elephants from Dumbo. We don't go and pretend that ants are bipedal or that elephants can fly, so why does everyone hope and pray that Tyrannosaurs were scaly and toothy?

Totally agree does it really matter?  Yes we'd all like to know what it really looked like and hopefully fossils will be found that will reveal it all once and for all but we also have to be realistic and there's a possibility we will never know, so it's best just to enjoy the depictions in art or model form you prefer. Why people actually get uptight about it is beyond me . it won't change anything. 

[Neosodon]

Tyrannosaurus is the most iconic of dinosaurs and is considered to be the most fearsome predator to ever walk planet earth.

If some random guy paints his trailer home solid black or camo pattern no one would really care. But if the president decided to paint all the capital buildings that way there would be major outrage. No one really argues weather or not Lythronax had feathers or not. Because of T. Rex's status it is surrounded in controversy. The scales and teeth have been defining characteristics of T. Rex for decades so when it was suggested that T. Rex may have had feathers and lips there was much backlash. This made the pro feather group have to push very hard to get their idea to gain some acceptance. And no one wants to be proven wrong after confidently pushing a view point for years. And this is why we have the T. Rex contraversy with die-hards and extremists on both sides.

[Patrx]

Well, what we're all trying to do in paleontology is to clarify our picture of the ancient past and the things that inhabited it. We're trying to identify those many pieces of the image that have to be filled in by speculation and close up the gaps with real information. Anytime something like this turns up to help us, it's "wrong" to be disappointed, even if the new, more complete image looks different from the one you were attached to.

However, people are complex, and we can all process things on multiple levels. You can be attached to your favorite picture of Tyrannosaurus or whatever else, and simultaneously accept that it's not "real." What's important is to be self-aware. Analyze, understand, and embrace why that image is important to you, and, if necessary, keep it in a separate part of your mind than the part that embraces new scientific discoveries and always wants to learn more about what really happened all those millions of years ago. That way, you don't have to let it stop you from learning and staying informed.

All that said, there have been some pretty lively discussions about this material among paleontologists and bloggers, and I really look forward to reading their upcoming posts. This thing is far from settled, I'm afraid.

[BlueKrono]

Neosodon - Excellent point, and comparison.
Patrx - I also agree with you. While I'm all for scientific discovery, I also have a fondness for old-school depictions of dinosaurs. I liken this with my fondness for kaiju like Godzilla. I know both are not real and are based only distantly on something that is, but I still think they're cool.

[Patrx]

Mark Witton weighs in.

[ImADinosaurRARR]

Mark Witton weighs in.

... I love this man :,) This is by far the most fair, educational and eye opening post about T-rex and it's relatives. I guess Neosodon wins and my next Rex will be scaly, that is unless anyone else has a counter claim.

Edit: However, I have to remain sceptical about the feathers to scales stuff. Looking into modern examples, no chick feathers have ever turned into reticular or vice-verser. Reticuler always stays as reticuler and feathers, if moulted, always stay as skin (at least from my knowledge). With everything that has been seen, tyrannosaur chicks were probably just as scaly as their parents.

[Neosodon]

Thanks for posting that Patrx, that article really cleared allot of things up. Best take on this find. He even brushed up on the cocadiles vs T Rex face debate we were having a long time ago. This part helps to clear up the feather loss debate. It looks like none of us were completely right.

"But what about arguments that the scale patches are tissues stripped of filaments before preservation, like so many 'monster' carcasses? Filament/scale combos do have precedent in dinosaurs, being present on the tail of Juravenator and those scales of Kulindadromeus with fibre-like tassels (Chiappe and Göhlich 2010; Godefroit et al. 2014). We know from modern animals that fibrous epidermal structures are especially vulnerable to decay and physical weathering, but is there evidence that this has taken place on the Wyrex Tyannosaurus skin patches? At present, it's hard to say because we have no idea what tyrannosaur skin looks like as it decays. It might be significant, however, that the scale patches look very similar across the Wyrex specimen, and that they resemble other tyrannosaurid skin impressions closely. We might expect some variation if taphonomy was really distorting these specimens in a major way, and we're not seeing that. Moreover, the Wyrex skin impressions, though small, are pretty high-resolution. The scales, and their intervening areas, have sub-millimetre proportions and sharply defined edges. There's no tatty scale margins, no obvious spaces for filament attachment, or linear structures crossing the scales to imply a rogue filament impression. We'll remain uncertain if these are anomalous, taphonomically-altered samples until we find other examples of tyrannosaurid skin, but there's no reason to be unduly suspicious of the the samples we have."


I hope this means the scaly T Rex's will become more excepted in the rest of the scientific and paleoart community.

[suspsy]

Brian Switek, whose article was mentioned in Witton's piece, also weighs in:

https://blogs.scientificamerican.com/laelaps/long-live-the-fuzzy-t-rex/

[Patrx]

Aha! Thanks, Suspsy, I should have included that article as well.
Personally, I'm still very much on the side of the fluff, in some form or other. A coelurosaur with no filamentous integument whatsoever just seems way too "out there".

[Neosodon]

Brian Switek, whose article was mentioned in Witton's piece, also weighs in:

https://blogs.scientificamerican.com/laelaps/long-live-the-fuzzy-t-rex/

I agree that T Rex likely had some fuzz and I find the article mostly valid but I have a few nit picks. The author seemed a little biased.

"I have to admit, I've enjoyed the tyrant's shaggy makeover during the last few years. A coat of fuzz only made ol' T. rex stranger, more like a real animal rather than a Steven Spielberg movie monster."

Also this I don't agree with eaither.

"There's little doubt that our favorite bone-chomper wore fluff. It's just a question of how much."

Elephants and rhinos have no scales so there is no alternatives for them to fall back on besides bare skin. Birds have have no scales except for on their legs so that is why birds have never completely lost their feathers. Feathers are just too ingrained into a birds way of life. Tyranosaurids had scales to replace feathers so it not as strange for them to completely loose their feathers as it may seem in comparison to modern animals.

I still find a complete loss of feathers sounding kind of silly but it is certainly likely. I think the author is jumping the gun by just assuming it had fluff. Ok it likely had at least a few wisps of feathers but he's just assuming it had fluff when there is no direct fossil evidence in favor if it. Fluff refers to thick and and heavy. But I'll give him the benefit of the doubt and assume he just made a poor word choice. If T. Rex had any really noticeable feathers they most likely would have been along the spine or head for display purposes as there would not be any other use for a small patch of feathers.

[stargatedalek]

"There's little doubt that our favorite bone-chomper wore fluff. It's just a question of how much."

Elephants and rhinos have no scales so there is no alternatives for them to fall back on besides bare skin. Birds have have no scales except for on their legs so that is why birds have never completely lost their feathers. Feathers are just too ingrained into a birds way of life. Tyranosaurids had scales to replace feathers so it not as strange for them to completely loose their feathers as it may seem in comparison to modern animals.

Think about what you said for a few seconds. There are plenty of birds with more (% of body covered in) scales than Yutyrannus, so no, there is absolutely no precedent for Tyrannosaurs having more scales with which to replace feathers.

[Neosodon]

"There's little doubt that our favorite bone-chomper wore fluff. It's just a question of how much."

Elephants and rhinos have no scales so there is no alternatives for them to fall back on besides bare skin. Birds have have no scales except for on their legs so that is why birds have never completely lost their feathers. Feathers are just too ingrained into a birds way of life. Tyranosaurids had scales to replace feathers so it not as strange for them to completely loose their feathers as it may seem in comparison to modern animals.

Think about what you said for a few seconds. There are plenty of birds with more (% of body covered in) scales than Yutyrannus, so no, there is absolutely no precedent for Tyrannosaurs having more scales with which to replace feathers.

I mean late not early Tyranosaurids. They really need to split the group in two.

[stargatedalek]

"There's little doubt that our favorite bone-chomper wore fluff. It's just a question of how much."

Elephants and rhinos have no scales so there is no alternatives for them to fall back on besides bare skin. Birds have have no scales except for on their legs so that is why birds have never completely lost their feathers. Feathers are just too ingrained into a birds way of life. Tyranosaurids had scales to replace feathers so it not as strange for them to completely loose their feathers as it may seem in comparison to modern animals.

Think about what you said for a few seconds. There are plenty of birds with more (% of body covered in) scales than Yutyrannus, so no, there is absolutely no precedent for Tyrannosaurs having more scales with which to replace feathers.

I mean late not early Tyranosaurids. They really need to split the group in two.

You missed my entire point. There is nothing about any of them that suggests that.

[Faelrin]

I really liked reading those articles. This gives me a better idea of what my favorite tyrant lizard may have been like in the flesh. The Tyrannosaurus Autopsy thing comes to mind, to be honest. Hope more is discovered. I ultimately don't care how it turns out to be, feathered, scaly, both, whatever. I'm just fascinated by this animal.

Also a question. So these were the Wyrex patches? Just finally published?

[Sim]

Also a question. So these were the Wyrex patches? Just finally published?

Yes.  The paper says the Tyrannosaurus skin patches are from Wyrex in the Methods section.


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Mark Witton's blog post was very interesting.  Also, some interesting things mentioned in the comments section by Matthew Martyniuk and Albertonykus, such as that a lot of times it's basically been said "feathers are utterly different from fur as insulatory structures", people are extrapolating incorrectly, as it's only pennaceous feathers that can work quite differently to hair as insulators, and pennaceous feathers are only known to be present in pennaraptorans (= oviraptorosaurs, dromaeosaurids, troodontids, avialans/birds and scansoriopterygids).  In contrast, down or protofeathers wouldn't function very differently to hair.

[Neosodon]

You missed my entire point. There is nothing about any of them that suggests that.

Ok, your being vague. Not quite sure what your getting at.

[HD-man]

... I love this man :,) This is by far the most fair, educational and eye opening post about T-rex and it's relatives. I guess Neosodon wins and my next Rex will be scaly, that is unless anyone else has a counter claim.

This. It's like I said in "Good, Semi-good, and Bad Dino Sources 3" ( http://blogevolved.blogspot.com/2016/09/good-semi-good-and-bad-dino-sources-3.html ), "If Conway et al. are the A-Team of paleoart (See "Good": http://blogevolved.blogspot.com/2013/03/good-semi-good-and-bad-dino-sources.html ), then Witton is the Lone Ranger ("HOME - markwitton": http://www.markwitton.com/ ): Whenever there's trouble, he rides in on his giant pterosaur & saves the day; His Spinosaurus posts are an especially good example of that ( http://markwitton-com.blogspot.com/search/label/Spinosaurus )."

Edit: However, I have to remain sceptical about the feathers to scales stuff. Looking into modern examples, no chick feathers have ever turned into reticular or vice-verser. Reticuler always stays as reticuler and feathers, if moulted, always stay as skin (at least from my knowledge). With everything that has been seen, tyrannosaur chicks were probably just as scaly as their parents.

To paraphrase Sim Koning, "Some bird species grow thick feathers over their foot scales seasonally [See "FIGURE 1": https://sora.unm.edu/sites/default/files/journals/condor/v079n03/p0380-p0382.pdf  ], and wood storks shed feathers from their necks as they grow scale-like plates in their place [ https://s-media-cache-ak0.pinimg.com/736x/a1/27/32/a127323f852b74706ef300afb7c386f7.jpg ]". I'm no expert, so IDK how analogous ptarmigans & wood storks are, but figured they were worth mentioning.

Aha! Thanks, Suspsy, I should have included that article as well.

I wouldn't have included it. I like most of Switek's work (See "Good": http://blogevolved.blogspot.com/2014/05/good-semi-good-and-bad-dino-sources.html ), but not his "Long Live the Fuzzy T. rex" article. To paraphrase Witton, said article isn't really new, but "echoes concerns about taphonomic interference" at best & comes off as "special pleading (excluding Tyrannosaurus from the same logic we would apply to other fossil animals when presented with this data)" at worst.

Personally, I'm still very much on the side of the fluff, in some form or other. A coelurosaur with no filamentous integument whatsoever just seems way too "out there".

Witton's T.rex IS filamented, albeit minimally so (Quoting Witton: "Scaly, minimally-filamented Tyrannosaurus. There's some tufts on the neck, but that's it. Is this model more consistent with the thermoregulatory requirements of a 6-14 tonne animal?").

Mark Witton's blog post was very interesting.  Also, some interesting things mentioned in the comments section by Matthew Martyniuk and Albertonykus, such as that a lot of times it's basically been said "feathers are utterly different from fur as insulatory structures", people are extrapolating incorrectly, as it's only pennaceous feathers that can work quite differently to hair as insulators, and pennaceous feathers are only known to be present in pennaraptorans (= oviraptorosaurs, dromaeosaurids, troodontids, avialans/birds and scansoriopterygids).  In contrast, down or protofeathers wouldn't function very differently to hair.

Again, this. I feel like I had asked someone about whether the hair-like (proto)feathers of tyrannosauroids would've acted more like mammal hair or pennaceous feathers in terms of thermoregulation, but can't remember for sure. In any case, I'm glad a real actual expert finally brought it up.

[stargatedalek]

Worth noting we don't actually know the state of tyrannosauroid feathers in life. It's more than fair to assume tyrannosauroids could have more primitive feathers due to their placement, but worth considering it's also possible the feathers from Yutyrannus are degraded beyond recognition, rather than completely filamentous. This isn't unprecedented, since ornithomimids and therizinosaurs have some similar impressions preserved to those of Yutyrannus and these two groups are far more derived and at the absolute least had pennaceous feathers ancestrally.

[Sim]

From what I've seen, it's agreed the feathers of Dilong and Yutyrannus are filamentous.  It has been suggested they could have been compound but still completely filamentous feathers.  I've not seen any palaeontologist suggest tyrannosauroids could have had pennaceous feathers.

Ornithomimosaurs and therizinosaurs aren't much more derived than tyrannosauroids, they branch off the coelurosaur family tree right after tyrannosauroids and compsognathids, with ornithomimosaurs first, followed by therizinosaurs.  Ornithomimosaurs and therizinosaurs are not known to have pennaceous feathers, not even ancestrally.  Pennaceous feathers are only known to exist in pennaraptorans, which are more derived than the previously mentioned groups.  There has been a discussion on whether ornithomimosaurs had pennaceous feathers, but that they had this kind of feather hasn't been shown to be true.  All of this is covered in this blog post by Darren Naish: https://blogs.scientificamerican.com/tetrapod-zoology/the-integrated-maniraptoran-part-3-feathers-did-not-evolve-in-an-aerodynamic-context/  I've quoted one relevant part below:

The proposal that ostrich dinosaurs had pennaceous feathers led to several reconstructions like this one (which is by me). I no longer think that this is correct and instead think that we should be depicting these animals with filamentous and quill-like structures only.

[suspsy]

Here's another good writeup on the topic. I'm in agreement with Holtz and Brusatte, especially the latter's point about science journalists have largely failed to read the fine print and instead chose to use hyperbole.

http://www.eartharchives.org/articles/is-the-tyrannosaur-feather-debate-really-over/