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Harry-the-Fox In reply to Flishstar [2018-06-28 14:54:18 +0000 UTC]

Actually Tyrannosaurid scales occur in areas other Tyrannosauroids have proven to have feathers; meaning it was most likely the feathers in these regions evolved INTO scales.

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Flishstar In reply to Harry-the-Fox [2018-06-28 18:55:07 +0000 UTC]

This is simply not true. The only debatable area is the neck which does not show scales, but naked skin.

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Harry-the-Fox In reply to Flishstar [2018-06-29 08:10:01 +0000 UTC]

Actually it is true. I looked at the photos of the neck skin slab in question, and they're clearly stark scales, complete with hard ridges.

That said, it's not the only area of overlap; the underside and back of the tail also show extensive plumage, with skin that is soft and slightly bumpy; while literally the opposite is demonstrated for Tyrannosaurus, whose skin samples mostly come from this same area (though probably closer to the hip, but nonetheless dispersed over a fairly wide area).

Furthermore, it is very likely that Yutyrannus huali's skull shows smaller fibers growing along the top of the snout... a contrast to Tyrannosaurid Daspletosaurus, against which evidence suggests had scales all around its entire head, based on scarring of the bone.

On the other hand, there simply isn't any evidence whatsoever to suggest any shared integument across all of Tyrannosauroids, and keeps pointing back to the theory that the Tyrannosaurids are simply an evolutionary divergent group as far as integument is concerned.

The fact we get a random sampling across much of the bodies of these two groups, each largely indicating scales without feathers, or feathers without scales between them further supports it.

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Flishstar In reply to Harry-the-Fox [2018-06-29 13:58:05 +0000 UTC]

Scaly tails and underbellies appear to be typical of basal coelurosaur. Yutyrannus and Dilong seem to be exceptions rather than the norm. Furthermore, the "scales" on the neck are bumpy, but that is where the resemblance to scales end. They lack any pattern, many lack a defined shape, and they area of skin we found d has many bumps, yet is only about 4 mm across. These features all completely contradict the bumps being reticulae, as no other dinosaur has retiuclae that small except in the tiniest of modern birds, and those that do still have some pattern to them, and of course their shape is not irregular. The closest match to an animal is actually elephantine skin.

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Harry-the-Fox In reply to Flishstar [2018-06-30 11:56:20 +0000 UTC]

Actually most Coelurosaurs demonstrate largely uniform coverings of feathers, including in dorsal regions, with the most certain exceptions being

1- Parave feet (which evidence overwhelmingly suggests were secondarily-evolved scales),

2- ornithimumus (densely feathered except its legs and underside- but lacking scales entirely).

3- Tyrannosaurids (which have no evidence of feathers at all, and evolutionary evidence their scales were secondarily evolved).

The "scales" on Wyrex were most definitely scales. Their pattern was clearly of flat-topped ovalular shaped protrusions, with large 'trenches' of depressed, flat skin between forming largely wrapping 'moats' around these protrusions, but largely lacking long rectangular criss-crossing creases evident of toughened bare skin, as seen in 'hairless' large animals like elephants or rhinoceros.

The similarity is closest to the smaller scales on a crocodile, or the smaller, rounder scales on the foot of a bird, and neither a bird lacking integument, nor an elephant.

In contrast, Juravenator's "scales" were spherical bumps- a shape not unlike the skin of birds. If anything, the ambiguity of evidence falls strongly against Juravenator, considering the basis of presuming these tubercules were scales at all was the absence of equally-strong evidence of feathers and corresponding structures in the area as the dorsal region (which has relatively poorly preserved edges of the skin, even though displaced quills of similar alignment are seen within the same photo). In contrast, the evidence of Tyrannosaurids being scaly but lacking feathers are multiple cases of unmistakable scales across two broad evolutionary branches of these animals, and a complete lack of any evidence of feathers at all.

The size of this neck patch would suggest one of two things.

1- It was representative of the broader region of this body, which is supported by the collective evidence of Tyrannosaurid integument and evolution of feathers and scales in general.

2- It was a non-representative patch, meaning the Tyrannosaurus had a largely feathered dorsal side to the coincidental exclusion of this one specific area, meaning the animal is a patchwork of feathered and scaly regions, due to a genetic effect activating sporadic feathers and scales, rather than broader regions of the body, as evidenced in the above examples, except the Tyrannosaurids.

With these established I don't really see how the relative size of the individual reticulae compared to other Coelurosaurs has any importance, considering the nature of any of the reticulae are unlike any other Coelurosaur anyway- if anything it's further evidence that Tyrannosaurids evolved scales from long, simple filaments of more basal Tyrannosauroids.

And there is absolutely no evidence to suggest Proceratosaurs were the exception and Tyrannosaurids the more typical among Coelurosaurs- if anything, the evidence suggests the exact opposite, considering the integument evidence of the former group plainly conforms to the expectation of Coelurosaurs having feathers, and all the collective evidence among every Tyrannosaurid shows only evidence toward scales, and absolutely no trace of any feather at all. Given they are more closely related to each other than any other Coelurosaur, it is more likely animals like Dilong and Yutyrannus represent the archetypical Tyrannosauroid than a compsognathid or Parave.

PS- will be away for a week, so sorry if I don't get back to you before then.

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Flishstar In reply to Harry-the-Fox [2018-06-30 15:36:21 +0000 UTC]

I'm just going to pull up an actual image of the neck bumps and compare them to actual reticulae. The fact we have to say "they don't match other coelurosaur reticulae" suggests they probably aren't reticulae.

thumbs-prod.si-cdn.com/h82xdeE…

Now here are some important details to note on this patch that indicate they are not reticulae:
1) They lack a definitive shape. Some are more circular, but a large chunk are also bloblike or triangular in shape. This is very attypical of reticulae in modern birds or in extinct Dinosaurs, including fellow theropod Carnotaurus. You may see a misshapen reticulae every so often, but for how tiny the skin patch is, it doesn't make much sense we'd see primarily these awkwardly shaped reticulae.

2) The size of these bumps is extremely miniscule. The entire skin patch is 5 mm across- this is quite literally the size of ONE reticulae on Carnotaurus. Now, if we were to assume this is because they are secondarily evolved reticulae and thus not going to be in a similar size range, let's look at this: reticulae size is pretty consistent (relative to body size) across all known Dinosaurs with reticulae- including modern birds, even those with very heavy feather density like penguins, or lower feather density like in ostriches. there is some slight variation among groups, but an animal as large as Tyrannosaurus with reticulae comparable in size to a passerine is very, very unlikely.

Now, these bumps do however, match the wrinkled skin of a rhinoceros or elephant almost perfectely. The irregular shapes of each bump, the small size, and the wrinkles running through them is very similar to elephantine or rhino-like skin:

www.featurepics.com/StockImage…


Furthermore, I'd hardly say feather distribution is uniform across coelurosaurs, let alone modern birds. Feathering on the legs and feet of modern birds and extinct dinosaurs alike is highly inconsistent, with some birds having fluffy down on their entire foot, including the foot pads, with others having legs bare up to the knee, or in the case of the ostrich, well onto the belly and sides. As you stated, Ornithomimids had bare legs, which is what you'd expect in any animal designed for sprinting at high speeds for long periods of time like ostriches, Ornithomimids, and Tyrannosaurids. Proceratosaurs may have had fluffy legs, but they were also far more generalistic in their hunting methods than the Tyrannosaurids, and it makes sense they would not have had to loose the feathering on their legs to effectively hunt. The loss of feathers on the legs and underbelly is a very specific adaptation for high-speed running over a good period of time in both ostriches and ornithomimids, and it should come as no surprise when we look at Alioramus, Albertosaurus, or the like. They're perfectly designed for speed, and it would probably be more surprising if they had feathered legs at all. The tail imprints are also all from the underside, and may also be related to thermoregulation at high speeds considering the use of the tail in running, though we don't have any modern analogues or studies on this to compare to, unfortunately.

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Harry-the-Fox In reply to Flishstar [2018-07-07 09:16:18 +0000 UTC]

1)

Actually, it is apparent the opposite is true;

On the Wyrex neck sample, it is clear the bumps all take a convex polygonal shape with no folding or wrinkling at any point. The bumps vary relatively little in shape compared to the bumps around them (at most, triple in size of the smallest in the region). In areas these bumps fail to tessellate, there is simply a spaced of depressed, flat region. On some of the shapes potentially indicating exceptions to this, you can see either surface damage, or stark lines cleaving these irregular shapes back into convex polygons.

On the rhinoceros, you can clearly see no such process occurring- with many of the shapes taking inversely convex to concave surfaces to tessellate with the neighbouring shape, with internal wrinkles and folds. The size of the stand-alone shapes varies far more dramatically (easily 9x or more on some of them). There is simply a lack of any surface failing to tessellate or reveal concave polygons and bare cavities.

One bears more structural similarity to scales with small patches of empty skin evident on archosaurs, the other to solid bare skin with creases and folds.

2)

Beyond being unusual, the relatively small size of the neck structures doesn't present any conflict that these structures are scales. I would point out that my exception to the 'consistency' of Coelurosaur scales- birds legs, do not have consistent proportion of integument scales, even on the same segment (a result of the broad anterior scales being evolved pennacious feathers).

The disparity between birds having feathers or scales on their legs is actually evidence of this process, as have been demonstrated in experiments which identified that very gene itself.

3)

No such consistency between running and integument exists; Carnotaurus, whose body evidently shows nothing but large scales, also shows massive physiological adaptations to its skeleton for augmented running. The physiological adaptation shown in Ornithomimus appears unique to itself- and I should point out, it completely lacks any scales at all, presenting no parallels to Tyrannosaurid dorsal regions. There is no evidence to suggest otherwise that scales, feathers or bare skin simply do not sufficiently inhibit or enhance locomotion.

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Flishstar In reply to Harry-the-Fox [2018-07-08 21:57:19 +0000 UTC]

I posted a picture of the scales themselves which show the opposite of that case, but I am no expert so I will concede it could be preservation bias.

Regardless, the size is still very unusual. Yes, birds have large, modified feathers on the top of the foot, but the ones of the sides and undersides are very uniform in size, or at least follow a pattern.

Ostriches having featherless sides and undersides is a pretty well known case of integument being lost to allow for running. It does not have anything to do with the locomotion itself, but heat generation by the muscles working so hard for so long. In Ornithomimids and Tyrannosaurids, which seem to follow the same adaptations, it would make sense you'd see the same thing.

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Harry-the-Fox In reply to Flishstar [2018-07-09 00:16:05 +0000 UTC]

Those were the very photographs I was comparing; the structural differences are substantial, based on what I described (keep in mind, I have a 4K monitor so they may not be as apparent on other systems).

But it still stands the Tyrannosaurus skin was covered in simple polygonal bumps with no internal creasing or concave forms, with frequent sections failing to tessellate (fit perfectly against) neighbouring bumps, instead leaving and empty cavity; which is fairly consistent with the structure of a scales, and unlike dense skin devoid of integument.

Quite possibly; though this may simply be a result of the structure of the feathers that grow in these areas themselves that the secondary scales evolved from. Either way, this largely leaves the outside evidence being animals whose necks are either feathered or bare, and animals with necks covered in scales that did not secondarily evolve from feathers. Point being Tyrannosaurids are the only animals known to have extensive body-wide evolution of secondary scales (bar extreme examples like armoured mammals, whose integument are quite more complicated)- so the lack of consistency against animals they have no basis to be consistent with doesn't strike me as a major factor.

There are a few problems with the model of ostriches.

1- relative birds, such as cossowaries and emus, did not evolve bare thighs, and are also high speed runners. It's more probable that Ostriches adapted for the temperatures in their surrounding environment than the internal heat generation of locomotion (keep in mind, the other two birds are almost as large, and also live in warm climates).

2- It still remains that Carnotaurus, with a clearly scaly body and coming from a likely hotter and more arid region, did not need to undergo integument loss or feather development to evolve into a runner.

3- Ornithomomids and Tyrannosaurids do not demonstrate identical evolutionary processes. Tyrannosaurids clearly retained their integument in the known regions, the integument merely changed structure (evolved from filamentous structures into reticulae). Ornithomimids actually lost their integument around the legs completely- no scales at all, they simply gave way to bare skin. The two processes are radically different, both in terms of evolution and in implications for the body. Furthermore, the changes of either animal aren't consistent across the body; ornithomimus's feather loss is largely concentrated around the legs and pelvis, but clearly absent elsewhere. In Tyrannosaurids, the feather transformation is present on multiple regions around the body.

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Flishstar In reply to Harry-the-Fox [2018-07-09 21:20:53 +0000 UTC]

All of the criteria you listed are things that you can see on tough skin of mammals as well- though of course not always the case. But the point is, the area of skin we have is tiny (smaller than a Carnotaurus's reticulae) and has maybe 60 bumps that are in good condition. If I were to take the skin of a rhinoceros from the neck, a piece the same or similar in size, I could very easily get a chunk that fits all this criteria as well. However, the criteria for reticulae these bumps do not fit is pattern (there is pretty much none- the bumps run along a crease in the skin but they are all of random sizes and shapes, which is very atypical in all known Dinosaur skin and skin impressions) and their size. These bumps do not match relative body size to any dinosaurs, be it those closer to birds or very distantly related. Carnotaurus, Triceratops, Anatosaurus, Kulindadromeus, modern birds, etc. their reticulae, even the smallest ones on the bottom of the feet and sides of the toes, show reticulae many magnitudes of size larger than those on Tyrannosaurus, so either Tyrannosaurids for some reason evolved extremely dense feather coatings highly unlike those seen in cold weather generas Dilong and Yutyrannus, or any other theropods known to science for that matter (including penguins, by a very sizable degree), or the reticulae are not reticulae at all. The size of these bumps is so minute that they don't really make any sense to be reticulae. Even Hummingbirds straight up lost their reticulae before they developed any that tiny. It just makes very little sense that the largest Coelurosaur of all time would also have the smallest reticulae of any known animal.

(as a side note, Reticulae can be concave just like they can be convex. A lot of birds have concave reticulae on their legs)

Cassowaries are fast, but they are not designed to run. They have next to no natural predators and thus have little reason to be as adapted to speed as the ostrich. Either way, neither animal has wings of any reliable size to cover any bare skin they'd have on their legs. Emus are not nearly as adapted for running long distances as high speed, either. Ostriches (and rheas, which likewise have similar patches on their thighs, but their legs are notably feathered- probably because they live in a significantly colder environment) have large wings used to cover the legs when cold. This is the same thing we see in Ornithomimids. It's a novel way of making a surface that can be exposed to cool off or covered to keep warm. Now, yes, Tyrannosaurids can't cover their legs with wing feathers for obvious reasons, but regardless it's pretty obvious the earliest Tyrannosaurids and their ancestors (see: Alioramus and Qianzhousaurus) were highly adapted runners, and we see this carried into the Albertosaurines as well. Tyrannosaurus itself seems to have been adapted particularly to walking things down (not that it needed to be particularly fast anymore, considering its prey options and environment). They were definitely doing the same thing as Ornithomimids. Furthermore we have almost no skin impressions from the upper leg on Tyrannosaurs, save for the even worse preserved and equally small pieces from the top of Wyrex's hips.

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Harry-the-Fox In reply to Flishstar [2018-07-10 00:17:23 +0000 UTC]

No, they're not. At all. No mammal has skin anything like this surface sample. I literally pointed out the differences in the two photographs and explained why they were not applicable. If the Wyrex skin had perfect irregular tessellation and no consistently obtuse reticulae structure, that would be a different story- but  it's clearly not the case.

To build on this example, we could look at the wrinkled, toughened (but bare) skin around the necks of Cassowaries- if any example were to present solid proof of the possibility of scales, it would be this bird.... yet the skin surface has the same non-structure or folds and random wrinkles as rhinoceros skin.... and no obtuse polygonal reticulae.

To put it another way, this animal's skin is more like the bare skin example than the Wyrex example.

As for bumps conforming to creases in the skin... this is applicable in all reptiles anyway- that I also checked. On many parts of their bodies their scales conform to larger skin folds.

So far, the only thing you have to go on is the small size of the reticulae relative to animals that as far as anyone is aware.... didn't secondarily evolve scales from filamentous feathers, so it's rather a pointless example as there is no basis to presume they SHOULD be similarly proportioned, particularly as I gave an example of disproportionate scales as a side-effect of the structure of the ancestral feathers in birds. Their scales being concave don't really matter- for Wyrex the scales are clearly convex and solid, singular bodies- this merely elaborates the contrast to toughened naked skin in the other animals.

"Cassowaries are fast, but they are not designed to run."

This applies to literally any other fast animal. The fact that almost all fast animals simply *can* run fast without evolving densely-plumed bodies and bare legs is more than sufficient evidence that such changes are far from necessary. In fact they're not even common- applicable to a slim minority of fast animals.

Which brings me to my next point- the dense plumage is actually used for keeping the animal WARM. While it deflects much of the suns rays, it also absorbs and retains a huge amount of heat.. substantially more than it deflects. The Ostrich has bare armpits that allow it to 'vent' the heat out to prevent overheating.

However, at night, the animal needs to keep warm- so it simply sits on the ground and folds up, its body and wings concealing their legs more-or-less entirely. Meaning in the day it is essentially naked (with a roof of feathers) at night it is essentially covered in feathers.

Now, in contrast to this, Tyrannosaurus rex was a contemporary of animals with evidence only of primarily, if not entirely squamous bodies- many of these examples are in a similar size range and body-density as Tyrannosaurus, many smaller.... yet they suffer no thermoregulatoy issues at all in this climate, which makes to prospect of Tyrannosaurus needing the ostriches' adaptations implausible.

Strictly speaking, most of these fast animals have elongated legs, enlarged thighs and various bodily changes clearly suited for enhanced running, so it presents a case of evolutionary augmentation, without the ostrich-esque integument.

"They were definitely doing the same thing as ornithimimids"

Not really. So far the only potentially similar thing they did was run- just like the scaly examples I gave.

As for the early Tyrannosauroids, there again simply remains no proof of any of these animals adapting the integument you describe.

For evidence of skin impressions, we have:

Tyrannosaurids showing repeated evidence of scales, and absolutely no evidence of feathers or any other skin surface, again and again. The lack of evidence for feathers over so many cases but abundance of scales in a random distribution around the body isn't a strong case that it coincidentally had dense downy coat *just* outside the reach of the material evidence.

The earlier Tyrannosauroids only show evidence of feathers and soft goosepimpled skin (indicative of skin beneath feathers)- a strong contrast to the Tyrannosaurid skin.

I'm sorry to say, but deductive reasoning that a Tyrannosaurid would need to have feathers for (X reason) simply doesn't stack up to the available facts that is simply didn't, nor did any of its immediate ancestors.

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Flishstar In reply to Harry-the-Fox [2018-07-10 04:24:11 +0000 UTC]

I could pull up lots of patches of mammal skin (and turtle skin for that matter) where this is indeed the pattern you see in small patches around folds and wrinkles.
i153.photobucket.com/albums/s2…
If we look at this snapping turtle, while it does have large feature reticulae on the lower portions of the legs, we see the skin where the legs contract shows the same bumpy pattern as the Tyrannosaurus skin and Rhinoceros skin.
www.tortoisetown.com/wp-conten…
another example, the neck skin of this diamondback terrapin.
www.4freephotos.com/medium/bat…
And again, rhinoceros skin, though this time on a black rhinoceros rather than an Indian.
christopherjgervais.files.word…
And here is a Javan rhinoceros for good measure.

Cassowaries are probably the worst example you could possible use for two reasons-

1) they are not large animals. at all.
2) Cassowaries have bald skin for display. Their skin is not toughened for defense as you would expect in animals known for their aggressive disputes with each other. The neck is a very vulnerable target, it would be more shocking to see the same smooth skin on a Cassowary (or the wrinkly wattle skin for that matter) on the neck than it would be armored skin.

You cannot claim Tyrannosaurus had scales on its neck and body without either claiming it is not a Coelurosaur (which is out of left field and wild speculation at that point, and thus should be discounted), Coelurosaurs are not basally feathered (again, a speculative claim that while not as wild is unsupported by all current evidence), or that the reticulae are secondarily evolved from feathers. We know the most primitive Paravians show complete feathering across the entire leg (this is not the case in more primitive groups such as Oviraptorids, keep in mind), yet this is not the case today, clearly, considering most birds have reticulae covered legs with scutae along the top. The last option is to acknowledge reticulae and feathers are not mutually exclusive, which makes the entire argument for or against feathers because of these tiny skin impressions minute. If we're to assume a feather density of half that of a penguin (which is of course very, very, very unlikely because of insanely dense this would be, and the sheer size of the animal) you're only looking at seven feathers on this patch of skin. Now, considering the size of the animal, realistically you'd be lucky to fit one feather onto that skin patch, let alone seven, unless we're going with wild speculation on the feather size of these animals.

That all said, reticulae and feathers aren't mutually exclusive, anyways, so it's not like even if they did turn out to be reticulae (which seems unlikely based on just about everything except being convex and their general shape, neither of which are even indicators of reticulae) that it would matter. What does matter is the biological basis on whether feather integument would make sense. We have reticulae from the undersides of Tyrannosaurids (which do not match the Wyrex neck material in size or layout, mind you) which could theoretically indicate that they are covered in reticulae rather than feathers. We have no dorsal impressions, which if anything is what you would expect if the dorsal regions are fluffy or bare skin because sandstone is notoriously bad at preserving fragile structures such as feathers (which is why it took so long to get good Ornithomimid material). Now, that obviously does not mean it was fluffy, but it does mean that it would make sense for us not to find this material.

you seem to be mixing up being fast and being designed to run for extremely long periods at high speed. Sprinters might have long legs for speed but lack any adaptations to dissipate heat, but that's why they're sprinters. Ostriches, Rheas, Ornithomimids, Wild dogs, etc. all have adaptations to dissipate heat readily because they're all long distance runners that move at high speeds. They also happen to share the same hind limb proportions you'd expect to see in long distance predators with Tyrannosaurus.

I am fully aware how feathers effect thermoregulation. If it was simply a matter of needing the bare armpits because they are black, we wouldn't see contemporary birds that are black without this adaptation, or if it was the size we would see this in Emus which have even denser feather coats and live in even hotter environments. We'd also see the brown females lacking this trait, but they most definitely still have bald armpits and sides. It's about the locomotion.

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Harry-the-Fox In reply to Flishstar [2018-07-10 11:04:50 +0000 UTC]

That turtle has wrinkled skin and sporadic scales. Beyond showing an example of scales shaping around folds, it shows gradually vanishing scales.... something not demonstrated in Wyrex's skin samples at all. You don't seem to consider the descriptive differences I gave important, but what I did was describe the properties of pebbly scales that are completely and utterly unlike any of the true bare-skinned animals. The fact that Wyrex matches this description and the bare-skinned animals completely fail to do so is a very telling point of difference suggesting these are in fact scales.

Cassowaries.

1- The size was irrelevant as far as integument structure of the skin is concerned. If you're implying the difference in size between it and an ostrich, I should point out that juvenile ostriches also have the bare skin features as adults, failing to show the size difference as a factor for thermoregulation.

2- The skin more closely resembles that on a rhinoceros than it, or the rhinoceros skin, resembles Wyrex's scales. My point was that the bare wrinkled skin looks like other examples of bare wrinkled skin, but are completely dissimilar to the photograph of Wyrex, for reasons I've painstakingly explained enough times already.

3- All of these animals are "runners", yet only one living and one extinct example actually conforms to your integument theory.

Feathers and scales being "mutually exclusive"?

Feathers ARE scales. They're literally just evolved scales. For dinosaurs and birds to even have feathers has been proven to be a result of evolved scales. The scales on birds are demonstrated to be secondarily evolved feathers. In other words, these "two" features are just different states of the same type of integument.

So, in terms of "mutual exclusivity".

1- They can't be both at the same time- an integument will either take the shape of a scale OR a feather.

2- All the evidence so far revealed fails to show anything but mutual exclusivity- that localized regions on the body are largely either scales or feathers, with no cases of sporadic scales and feathers shown (this includes Juravenator). The closest to an exception (and by no means an actual exception) are the ceratopsids with tail plumes. IF you were thinking of Juravenator, then I'm sorry, but that IS an example of ambiguous integument more likely to be skin.

3- The most important aspect of mutual exclusivity is in the fossil evidence itself. No Tyrannosaurid fossil shows even the faintest evidence of feathers, but overwhelming evidence of scales. In contrast, other Tyrannosauroids show absolutely no evidence of scales, ironically given your insistence that they certainly would. The whole "Sandstone doesn't preserve feathers well" argument has been debunked by Ornithomimus. It's no rationale that the missing integument is 100% scales, especially given the evolutionary factors I described multiple times.

So far, the entire basis for Tyrannosaurids having feathers is entirely based on speculative beliefs being used as a deductive basis to make presumptions, and ignoring the real life evidence contradicting either the belief itself, or the applicability to Tyrannosaurids..

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Michell-Vall In reply to Harry-the-Fox [2018-07-10 17:28:03 +0000 UTC]

You completely misunderstood the turtle examples. Flish is talking about the skin on the neck and torso, not the defensive scales on the feet.

Descriptions mean jack all here, have you seen the impressions? I've seen some (though not the "Wyrex" impressions), and I've seen extensive photos of the ones in question, and Flish has also at least seen photos of them. The Wyrex impressions look nothing like the other impressions (which are actually scales). The parallels to thick skin of modern animals are frankly uncanny, and if you used your eyes instead of going off of established biased descriptions you could see very clearly these patterns are irregular and random, something never seen in scales.

You're also ignoring what is potentially the closest in appearance to Tyrannosaur impressions, the Prairie Chickens display patches. The texture is near identical.

www.inhf.org/webres/image/blog…

So you really think a rhinoceros and cassowary have similar looking skin? They really, really, don't. Cassowary skin is soft and smooth, abnormally soft for bird skin even. And the large lumps on it are composed of soft tissue of the neck itself, those are not skin texture (they're also huge). And rhinoceros skin is extremely rough with large irregular bumps and texture.

Cassowary are not "runners". Most species even live in dense rain forests. Frankly this claim comes out of left field and is completely without context. What are "all of these animals"? Cassowary and rhinoceros? Tyrannosaurs? Or are you actually claiming that snapping turtles are "runners"?

Scales and feathers are not mutually exclusive. As anyone who's even seen an owl up close can tell you. But there are also many varieties of chickens and pigeons that can even grow "flight" feathers alongside scales on their feet. We even have fossils from Archeopteryx showing that it too had feathers growing through its scales.

Three ornithomimid fossils (out of dozens of specimens) with extremely poorly preserved feathers does not prove sandstone preserves feathers well, just that it's possible. But technically it's possible for a can of mayonnaise to fossilize and preserve feathers, the odds are just ludicrously slim. Just because something is possible doesn't mean it's at all likely.

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Harry-the-Fox In reply to Michell-Vall [2018-07-13 08:05:17 +0000 UTC]

I knew- the point is we literally DON'T SEE THAT HAPPENING ON WYREX.

I've seen the impressions, and if you were paying attention to this conversation I described them in much detail, and exactly why they are (a) like scales and (b) nothing like bare skin.

The 'uncanny' is literally completely lacking notable features in any rough skin in any animal, but retaining obtuse polygonal bumps.

Also, if you paid attention, you would have already seen the cassowary examples.

Again, look at the patches, I'm not explaining them in detail again for the benefit of saving you the trouble. They both have random creases and folds that tessellate with no fundamental structure. Wyrex's neck lacks exact tessellation, but does contain roughly circular shapes with no internal disruption.

Cassowaries can run quickly, as can plenty of other birds lacking the 'bare legged' description,including emus and roadrunners. I could cite a number of birds, a number of long-legged scaly theropods, and could diverge to include literally every mammal and fast-moving lizard. It's a complete non-factor for being able to run.

Are you going to tell me literally none of these other animals are "runners" now? The Ostrich, and potentially Ornithomimus, are the only known runners that DO have this evolutionary feature, against literally every other 'running' animal on the planet.

I've trawled through enough photographs to find a few (admitedly low-res) photographs that could demonstrate your point.... problem is to get there I had to go through a very large quantity of photos that demonstrated high-res closeups of exclusively feathered or exclusively scaled feet, suggesting this isn't the most generalized property of owls (and knowing silkie hens I looked at, their feathers protrude further down alongside the scales, but aren't interspersed among scales. So we have one derived member of one animal family, against an animal whose fossil record, again, shows no evidence of feathers (again and again).

It's irrelevant- the "sandstone doesn't preserve feathers' argument has been proven false. It's definitely NOT evidence that Tyrannosaurids DID have feathers and consistently failed to preserve, and I don't see why you insist on trying to pretend it is somehow more potent than the ACTUAL EVIDENCE.

Kindly re-read from the start of the discussion.

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Michell-Vall In reply to Harry-the-Fox [2018-07-14 02:32:49 +0000 UTC]

Why should I care about your description when I can look at the actual impressions for myself?

OK so you admit the patterns are irregular in size and placement. How exactly is that evidence of scales? Scales are not irregular. Can you make the argument this is some armored surface ala Plecostamus catfish or crocodilian faces? Sure. But that's still not scales. And it's far less likely than this being soft tissue.

Yes, cassowary can run quickly, so can peafowl, guinea fowl, geese, flamingos, and ducks, doesn't make them "runners". Cassowary do not rely on speed to catch prey or escape from predators (their only natural predators are crocodilians anyway). That's like saying toucans are ambush predators, yes they can ambush, doesn't make them ambush predators.

Ostriches have bare legs to cope with overheating from running fast for long periods of time in hot climates. Roadrunners don't have bare legs because they're A) 1:40th the size and B) don't have to cope with running for hours at a time without stopping.

Most birds have largely bare legs anyway, the only thing unusual about ostriches is the thigh and underside being bare. And again, ostriches are large nomadic animals that live in hot deserts, they are not comparable to any other large modern bird.

Running lizards, AGAIN, do not need to run for hours at a time in hot climates. And I don't exactly recall seeing any feathered lizards anyway. Lizards are 100% irrelevant to discussing soft tissue in dinosaurs.

There is no mammal that runs for hours on end in hot deserts like ostriches do.

So, even though you acknowledge feathers and scales can grow in the same places on an animal, you refuse to acknowledge it because I didn't specify a particular species of owl? That is rather pathetic frankly. Shows how much you actually care about evidence or logical comparisons.

Tyrannosaur fossil record DOES show evidence of feathers, genetic evidence is still evidence.

No one is saying sandstone can't preserve feathers, just that it's extremely rare. There is no evidence of extensive scales on Tyrannosaurs, so I don't understand why you're so insistent on making it up.

I read it all, your phrasing is just so abhorrent I can barely follow it.

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Harry-the-Fox In reply to Michell-Vall [2018-07-15 01:50:23 +0000 UTC]

Then by all means look at the impressions- though I'd say you're not looking hard enough if you can't see the obvious differences.

Scales ARE irregular- literally no such animal exists with 'regular scales', simply because there is always a joint, edge or fold that forces the scales to take irregular shapes or various sizes- it's a complete non-issue.

And what I was actually explaining was that all of the bumps on the "skin" photos tessellate as folds, with absolutely no uniform structure except conforming to these folds. This is not even close to the case of wyrex, where litearlly every bump is a singular obtuse-angled polygon, surrounded by trenches- frequently these bumps don't exactly tesselate, leaving a larger patch of empty depressed skin between them... this is literally the same description for the sections comprising of round scales on all living archosaurs. No 'bare skinned' animal alive or dead has skin impressions like this, and certainly not in the photos provided. Feel free to point out some detail I missed in describing these, but so far it seems like I've been doing that for you instead, while you parrot a claim you heard, and appear to be repeatedly failing to understand the description I'm actually giving you, if the only message you gained last time was me telling you "they are irregular".

Sorry, but your point about "runners" is hilarious. So let's get this straight- animals that are more than capable of running fast aren't necessarily "runners", but archosaurs with dense plumage but bare legs ARE runners. Got it.

Ostriches don't rely on running to catch food- their diet is mostly herbivorous with occasional small animals. Emus DO have fast predators (dingos), yet they don't have bare thighs. The point I was arguing before, that clearly sailed over your head, is that loss of integument was a necessary feature of being able to run- literally no animal, let alone bird, EXCEPT the ostrich demonstrates this happening. Birds don't have "bare legs", the fact you don't fully grasp the difference between 'bare' and 'scales' is alarming.

And sorry, but your claim "ostriches have bare legs because the running makes them overheat" is absolutely and demonstrably false. Ostriches  have bare legs, as well as bare armpits and bare undersides to their wings, solely to vent heat from their hot climate. The proof- an ostrich merely needs to open its wings wide to vent heat... yet when running, they rarely actually do this. Meaning running doesn't cause them to overheat, meaning they did not evolve the way they did to cope with running. If it did, they would ALWAYS stretch their wings out completely to maximize the heat venting. I'm not sure why I'm explaining this to you, you clearly don't understand.

Actually, lizards and mammals are only irrelevant beyond your insistence that "running" is 100% dependent on integument loss in the legs- had you bothered to read the conversation like I asked (or better yet, do actual research instead of believing whatever source you are getting your information from), you would have known that Carnotaurus is a squamous animal more heavily adapted to running than any Tyrannosauroid- painstakingly pointing out how irrelevant your "runner" model really is.

"There is no mammal that runs for hours on end in hot deserts like ostriches do"

You really should check that claim (and show me, because I'm sick of digging up your non-existent 'evidence'), because so far I've only found sources suggesting the exact opposite to literally both claims you just made in that sentence.

No, I'm explaining to you that you selected one species of owl out of hundreds that don't show that feature, and suggesting it's a rare, derived feature belonging to a group of animals that don't actually display this feature in general, with plenty of cases their integument transformation largely shifts from one type to the other type, as demonstrated in experiments on pigeons.

I could as easily say this is irrefutable evidence Tyrannosaurus had a rooster comb, because some species of chicken also have these combs. Again, I expect the significance of why this isn't strong evidence will completely fly over your head. The simplicity and sheer overwhelming frequency of scales evolving into feathers as a broad, regionalized occurrence and the massively underwhelming cases of the opposite (mixed coverage) should be a hugely important factor. If birds frequently uniformly change integument, the chances of this being what occurred in Tyrannosaurids is high, and the chances of sporadic integument very, very, very low.

"Genetic evidence". Oh boy, now I know you have no clue what you're talking about.

The genetic evidence is literally the basis that the researchers suggested Tyrannosaurids were covered in scales. Were you actually unaware of this? Did you honestly actually believe the entire basis scientists are now saying Tyrannosaurus was scaly was because of Wyrex's fossil? Four other Tyrannosaurids also have evidence of scales on other parts of their body- this is the genetic evidence.

I suggest you start reading the study. The evolutionary evidence among Tyrannosaurids and broader Tyrannosauroids suggest the scales exist because they evolved from ancestral plumage of earlier Tyrannosauroids... the exact same reason why birds have scaly feet today. For FIVE Tyrannosaurids to have scales in areas other Tyrannosauroids have feathers, but repeatedly fail to show evidence of feathers, there can only be one reason. My point about sandstone is you can quit bringing it up as some kind of counter-evidence. It's probably one of the weakest excuses... until you managed to top it with your "Runner" theory, that is.

"your phrasing is just so abhorrent I can barely follow it. "

Translated- "I'm not smart enough to understand anything except dumbed down language and broad summarized claims, this is somehow your fault". None of the things I said are actually that difficult to interpret.

Next time you try to pretend to be smart, don't repeatedly reveal the truth of the opposite. I'm honestly getting really sick of checking your claims and spoon-feeding you very basic and simple information rebuking all of this, that you clearly can't process.

So again, do some actual research before you make another response, and stop wasting my time with stupid responses until you can back them up with something scientific (and you can prove you understand these sources, to save us both trouble of you skimming a discussion section and citing it as proof and sending another reply).

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Harry-the-Fox In reply to Harry-the-Fox [2018-07-15 23:37:47 +0000 UTC]

Dear Michelll-Vall

(this reply is actually intended to your comment below... the one where you tried to push a losing argument about running ostriches, then concluded with a rude 'final word' before blocking me so I couldn't respond to it..... nice try though)

A final note about you maintaining your ridiculous "Ostriches must have bare legs because running makes them overheat" theory- I thought you'd be too stupid to follow this simple logic.

If Ostriches overheated specifically from running, they'd always open their wings out to prevent this happening WHILE running.... yet the abundance of video evidence of them NOT doing this, with plenty of video evidence showing them doing it while idle. Ergo, their 'overheating' is not based on them running, but the fact their climate is hot.

I'm being really honest with you, if this simple piece of logic was too confusing for you the first time, let alone the second, you should definitely avoid any future in paleontology or science, let alone pretending to be an expert in anything. It will save you future embarrassment over being corrected by people that don't pull facts out of their ass, and a lot less young people will be misinformed by your bullshit "theories" and fraud claims.

Good riddance to that I say, and good riddance to having to read any more of your rampaging stupidity.

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Michell-Vall In reply to Harry-the-Fox [2018-07-15 17:29:08 +0000 UTC]

Ostriches overheat because they run for extended periods of time in fucking deserts.

You're an idiot and I'm done acknowledging you.

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Flishstar In reply to Harry-the-Fox [2018-07-10 17:22:17 +0000 UTC]

yeah, the turtles show wrinkled skin. Just like the Wyrex and rhinoceros skin as I was pointing out.

And I do not take your "descriptive differences" seriously because they are not indicative of reticulae. Convex bumps with space in between them is exactly what we see on some patches of turtle and rhinoceros skin (though not all of it, just like on Tyrannosaurids), in the same areas we have the Wyrex sample from because these are areas that need toughened skin for protection. This is not what we see on cassowaries, we see smooth skin or heavily wrinkled wattle skin. Even then, the Wyrex bumps still don't match the actual reticulae seen on other Tyrannosaurids in size or appearance at all, so it's very unlikely they would be the same structure.

Not sure how to break it to you, but there are many, many birds alive today with fluffy feet or legs that still have reticulae underneath. Obviously, they're not going to grow from the same spot- they're both derived from the same thing. But when you're looking at a skin piece smaller than the gap between those feathers, saying "oh it must be scaly" is a very, very, very large conclusion jump.

Sandstone is still bad at preserving feathers. If you've actually seen the Ornithomimid feather impressions, they're very faint and certainly not the norm, as there are many other Coelurosaur groups in North America we have no evidence of feathers for directly, but we see feathers in their close relatives in Asia. Claiming that Sandstone preserves feathers well is a very large conclusion to draw from three specimens that were preserved so poorly we can't even tell for certain whether the feathers were pennaceous.

Baby ostriches do not have bald skin patches and I seriously can't say anything else about that because it's not even debatable. They may have a thinner coating of feathers on their sides and bellies, but they are still feathered there nonetheless.

Regardless, the argument was never even that Tyrannosaurids MUST be feathered. My argument was that it's premature to claim they were scaly based on current evidence, when we see bumpy skin on the neck from Wyrex (even if you would like to try and claim this is not the case, it's pretty clear that the bumps still do not match reticulae- they have no pattern, an indicator of reticulae, and their size does not match any known reticulae) and scales only from the lower half of the animal.

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Harry-the-Fox In reply to Flishstar [2018-07-13 08:30:22 +0000 UTC]

That's not what I said.

When I said "convex", I wasn't meaning the scales are bumps (perpendicularly from the skin)- I meant the  lateral edges surrounding each bump consistently show external angles LARGER than the internal angles. In that they're all "rounded" laterally. Like scales, and literally as far from the skin examples as possible, which don't show this happening at all.

You say this is similar to bare skin, but literally every photograph shown so far has only proven my point- none of skin examples show this happening. The only photo where this DOES happen is Wyrex's neck.

So far, I've seen a handful of owls (blurry photos mind you), after trawling through images of owls that show purely scaled or purely feathered feet with evident bare skin underneath, and chickens with feathers growing along (but not interspersed between). So far, you've given me an example of what seems to be an uncommon, if not derived feature as a counter-example to multiple fossils that fail to show this feature actually occurring at all (and pointing out that no fossil to date shows this, even ones where feathers and skin are both preserved- including Juravenator). And sandstone is poor at preserving any soft-tissue. It's hardly a basis to assume it was likely Tyrannosaurids had feathers that simply didn't preserve, when the same was true between patches of solid scales on the tail,as well as plenty of other skeletons where the skin failed to preserve at all.

Ostriches? Juveniles, sub-adults, do. And I've seen plenty of photographs showing clear pink bare patches in roughly the same areas on babies as adults. The important part is that it completely negates and size-based thermoregulatory necessity against more densely feathered relatives like emus.

The problem is, you're ignoring that evidence and insinuating it's somehow not what it clearly is. I've already gone to the trouble of explaining the differences and similarities that are demonstrated on your own photographs, and so far you're simply repeating your original broad claim that was literally contradicted by what I described.

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Dontknowwhattodraw94 In reply to Flishstar [2018-05-28 21:08:19 +0000 UTC]

I'm not so sure. If you look at the impressions from Bell et al. they all look quite the same in shape and size: the neck patch really doesn't differ a lot from those from the tail vertebrae for example. Unless you mean those all are just skin.

I have some problems with your points about Columbian mammoths being as hairy as woolly mammoths. Animals their fur can differ a lot depending on the climate they're in (e.g.: North American grey wolves vs. Indian grey wolves) Note, I'm only talking about the diversity IN a species. Columbian mammoths are a species on their own so a lot could've happened with the density of their fur and I would say chances are high they differed from their ancestors in fur density. It's the same reason why I'm not so keen on people reconstructing Megatherium with the same long fur as is found on Mylodon. A herbivore is going to have to cope with heath a lot more than a carnivore because of the larger gut system.
I find Deinocheirus and Therizinosaurus not such good comparisons because they are herbivores with a large gut system (especially Therizinosaurus) and they lived in a warmer climate. Lots of feathers aren't necesarry for them. 

Take into account that even though we know Hell Creek climate it still wouldn't be as cold as regions today with a similar mean annual temperature because it was more stable IIRC.
Any reptile has fat so it seems fair tyrannosaurids had it too. Makes sense then that it would help in keeping warm during winter.

I'm not saying tyrannosaurids weren't totally featherless of course. I just don't see a fully grown rex being as fluffy as Saurian's previous model.

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Flishstar In reply to Dontknowwhattodraw94 [2018-05-29 01:19:09 +0000 UTC]

I dont understand what you're talking about. We have long for from columbian mammoths. An animal twice the weight of a tyrannosaurus with a much more compact body in comparable climates (except more exposed and dry)

As for mylodon and megatherium, myloson was tropical and woolly, and megatherium lived in a temperate climate. It doesnt make much sense that if a woolly relative was living in a tropical climate, that the temperate relative would he hairless, especially with how low xenarthrans body temperatures are.

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Harry-the-Fox In reply to Flishstar [2018-06-29 08:16:25 +0000 UTC]

Apparently body-size and climate were both disregarded as factors, given that

1- Yutyrannus lived in a similar latitude as Tyrannosaurus Rex and the temperatures weren't substantially different.

2- Hypothetical modelling suggests the first Tyrannosaurid to develop scales may have been smaller than Yutyrannus

3- Many contemporaries of Tyrannosaurus show evidence of being primarily (and often entirely) squamous, despite being smaller than Tyrannosaurus.

Overall, the most likely explanation is the respective integuments are merely inherited traits from ancestral animals (the Tyrannosaurid ancestor secondarily-evolving scales).

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Flishstar In reply to Harry-the-Fox [2018-06-29 14:02:39 +0000 UTC]

The reason I brought up size is because Mark Witton was adamant this is a factor despite all basic knowledge on the subject and a lot of people took his word for it because hes Mark Witton. If Tyrannosaurus was scaly, it certainly was not because of mass.

Also, the scale impressions we have for other derived Tyrannosaurs are all from the underside or legs of the animal. While primitive coelurosaurs do seem to have a large array of feather distribution, we do see some like Juravenator who have scaly undersides but fluffy backs and frontal areas.

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Harry-the-Fox In reply to Flishstar [2018-06-30 11:03:09 +0000 UTC]

I've viewed both animal's skin samples myself.

The skin sample on Juravenator (specifically the one that Gohlich and Chiappe investigated with the UV light) shows round tubercules on both the dorsal and ventral regions of the tail. The latter shows clear filaments protruding beyond the dorsal silhuette of the skin; the former section does not- nor for that matter, show a clear silhuette either, suggesting it is also more poorly preserved at the edges. The basis the researchers inferred the dorsal region was squamous was due to the lack of evidence of feathers in that region. However, there are possible filaments displaced some distance from the dorsal region of the tail (leftwards in the photograph "a"- just above the 'total body' photo superimposed over it).

In terms of "obviously squamous" the neck patch on Wyrex vastly surpasses it as evidence of scales on that region (which I'll describe below in my other reply).

This would suggest one of two things- either;

1- Juravenator has dramatically differently-shaped scales to Tyrannosaurids, and these scales are spread across the entirety of its tail, but with a bristled mohawk on some of the portions.

2- The entire tail was feathered, and the tubercules were simply goosebumps on the skin, similar to modern birds. The evidence of filaments immediately connecting failed to preserve on the underside, as well as the edges of the underside itself. The larger tubercules are larger bumps contain larger feathers, and the tips are the displaced filament-shaped also glowing in the UV light.

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Blomman87 In reply to Flishstar [2018-06-29 19:43:11 +0000 UTC]

The Newest updated version - Tyrannosaur skinchart    What do you mean with the scale impression we have from other derive Tyrannosaur are all from the underside of the legs of the animal?

 If Tyrannosaurus was scaly, it certainly was not because of mass. Wait is there any hypothetis to discredit this argument? 


Take the climate for example it can change more dramatically on a geologic timescale than many people realize. 15,000 years ago, my backyard was under 400 feet of lake water fed by glaciers. Somewhere around 3000 years ago, one of the last vestiges of that Pleistocene lake--the Great Salt Lake--dried up completely. It flooded in '83 (and if you've ever seen the original Carnival of Souls, that was Saltair's final destruction) but nowadays we're talking xeriscaping for the sake of water conservation.

for example the Hell Creek Formation records, what, 4 million years of time? During which the Cretaceous Seaway flooded and then receded for the last time? With all that climate changing environmental craziness going on how can we conclude the qoute on qoute climate as evidence is a far shot. So climate might not even have the affect on these integument as we might think due to the fact with have scaly nodeosaurs anotactopelta in what we believe is a cooler climate coexisting with filamented theropods but that needs to be tested.

To qoute the abstract of Y huali filament - we don't know yet because the evo devo hasn't been done on them yet. However,people call them feathers in that case we can't call them feathers because they don't match the morphology, developmental processes, or other correlates known for accommodating feathers. *


What about thermoregulation, its yet to be proven because the theropods closest relatives shares birds and crocs both traits of Ectothermic and endothermic, and that is another thing to be tested

 One thing is also interesting that the dinosaurs that shows preservation of filaments are smaller wich have higher surface to body size ratio, wich have greater need for insulation if they regulate temperatures internaly we talking basal Tyrannosauroids and earlier ancestors. 

We see the same thing with the late ceratopsian, their ancestral shows filament preservation but as evolution and 48-50 million years and new species came along and til the end of the cretaceous we see Horridus with great preservation of integument with no filaments , the same goes for Tyrannosauroids, just because we see filaments in earlier ancestors , does not mean a 7-8 ton Tyrannosaurus rex would need insulation evolution is not stable, and the elephant analog is quite different.

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Flishstar In reply to Blomman87 [2018-06-30 01:53:57 +0000 UTC]

The skinchart you linked has skin only on the underside of the animal except in two small areas on the hip and on the neck. The hip is pretty much of a mystery in other basal coelurosaurs as well, but based on the images I've seen, it looks an awful like the bare skin on the neck. Furthermore, just because we see skin impressions does not mean there was an absence of feathers- oftentimes when an animal decays, the integument will fall out before the skin rots, allowing a fair amount of time for the skin impressions to be left and not the feathers.

The climate can shift very quickly, but large animals can deal with climatic shifts far easier than smaller ones. A leatherback sea turtle can survive in very cold water or very warm water just as easily, but the smaller green sea turtle struggles to survive in cooler waters and is known to bask on land only in areas where the water temperature is cooler. And this is in animals that never evolved fluffy integument. The three dimensional nature of fur and feathers allows it to function even more effectively for thermoregulation than bare skin- the only time we see any modern animals loose integument is when they become semiaquatic (As was the case with elephants and rhinos) or in very specific and specialized niches such as in naked mole rats. I think you can agree Tyrannosaurus was not extensively burrowing or semiaquatic in any of its ancestors, so changing its integument over time is not very likely.

I don't think bringing up Yutyrannus's feathering is really relevant. The preservation of them is too poor to say really anything about their structure and how they would relate to other feathers, but phylogenetic bracketing tells us that Yutyrannus had ancestors closely related to animals we know had feathers, so to even suggest they might not be feathers is pretty silly.

We know Dinosaurs were endothermic, as there are multiple ways of finding this out, though I honestly don't know the exact ways off hand. Either way, Tyrannosaurus was almost certainly warm blooded, and any fluffy integument would have helped the animal greatly.

We see evidence of feathers in small animals because of preservation bias, but even then we see larger animals such as Deinocheirus that show evidence of feathers (in this case, the existence of a pygostyle to support a fan of feathers on the tail)

Psittacosaurus is the only Ceratopsian we see any evidence of "filaments". These filaments are structurally completely different from feathers or even the integument seen in Kulindadromeus, and the rest of the animal is completely scaly, anyways. You can't compare Triceratops and Tyrannosaurus in this situation because their ancestors show completely different body integument.

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Blomman87 In reply to Flishstar [2018-07-02 12:50:11 +0000 UTC]

I think you missunderstod my questions wich relatives of (Tyrannosauridae not wich Tyrannosauroids) have filaments? What you linked there is basal Tyrannosauroids like Yutyrannus huali but those goes of into a different branch of proceratosauridae wich i would assume you know if you read the parsimony cladogram conducted by mr Brussate in colaboration with dr Carr.  www.nature.com/articles/srep20…

Again you ignoring that these milimieters across shaped polygonal integuments we have are not scutae and the scales of birds are composed of the same keratin as beaks, claws, and spurs. They are found mainly on the toes and metatarsus, but may be found further up on the ankle in some biand not actually true scales and how many non avian dinosaurs from Tyrannosauroids or for that matter have this kind of keratin? vit and caldwell, 2009.

Phylogenetics suggests that they're a form of beta keratin like croc seen in Tyrannosaurines. 

This is the problem with the analog of filaments towards avian birds, we just assume they correlates without actually conducting research on the integuments themself. 

Just another example in psittacosaurus and tianyualong which according to fairly recent work (Mayr et al 2016) failed to establish any homology between them and feathers, but correlated it to the sort we see in turkey beards. They are also suggesting that we should with caution aproach whatever structure we see in these non avian dinosaurs as "feathers"

research-information.bristol.a…...

And since evo devo is yet to be conducted we dont even know exactly what kind of structures in the matrix of these filaments we see in Huali, if you noticed in the abstract more analyse needs to be done on them.

Anyway i find this subject tiredsome. And we should be happy that pieces falling into place in recent times no matter genus and even more is coming on the horizon 

and any fluffy integument would have helped the animal greatly.  based on your on theory?  If we dont even know what kind of integumental structure we see we cant conclude anything but well theories.    

We see evidence of feathers in small animals because of preservation bias any citation you can provide regarding that statement 

 The publication of Jacob Vinther Saittal et al - 2018 the general discussion of fluvial do not alter the apperance of feathers 

link.springer.com/article/10.1…Hantera

LINK.SPRINGER.COM

Experimental subaqueous burial of a bird carcass and…

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Flishstar In reply to Blomman87 [2018-07-02 23:46:17 +0000 UTC]

We don't have any solid evidence of feathers in Tyrannosaurids because they all come from rock that's poor at preserving fine details such as feathers- This is pretty common across most of North America and is why we see the best preserved feathered Dinosaurs from Asia, and even then not all of Asia is amazing at feather preservation because of the type of rock found there. Most of Mesozoic North American fossil sites are sandstone, which is notoriously bad at preserving significant detail in fossils- the only real feather impressions we have are the (rather poor) impressions of Ornithomimus feathers. The Nemegt formation, just about the only Asian site we see truly large Coelurosaurs in outside of North America, is also mostly sandstone. We did however find a pygostyle in Deinocheirus, one unrelated to the pygostyles found in Oviraptorids or birds, which indicates it likely had a tail fan.

I honestly don't know what your argument about filaments is about. Are you suggesting Tyrannosaurines are not Coelurosaurs, or that feather-like structures evolved independently more than once in Coelurosauria? Either way, it is wildly speculative to assume either scenario is true and I don't see its relevancy because of that.

Never said that the reticulae on birds and dinosaurs are true scales. I am fully aware of the fact that feathers and reticulae have switched from one to the other in Coelurosauria at least twice, though keep in mind feathers only became reticulae in areas that need a durable protective layer, namely the feet and lower legs, with other areas becoming bare skin if feathers were a liability in that area.

Furthermore there is a significant difference between saying if Ornithiscian fluff is feathers or a Coelurosaur, a much less inclusive group which is far closer to birds, fluff is feathers. If we want to get really technical it's not actually accurate to call any integument feathers unless they are on a bird- but for the sake of simplicity if it is homologous to feathers it is generally considered a feather. 

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EnvyMay In reply to Flishstar [2022-06-18 12:35:09 +0000 UTC]

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Blomman87 In reply to Flishstar [2018-07-03 10:30:16 +0000 UTC]

Your argument is that it must be filaments preserved because it is colerosauriae wich is a weak argument.  We have filaments preserved in a Basal Tyrannosauroid from 48 million years earlier in a geological time scale but we also have integument from exact the same formations for Tarbosaurus approximately 39 million years later.

But we know very well that the body consists of carbon hydogen, water and other kinds of molecules, bacteria comes in to break down these carbon molecules and they get replaced by on organic like hematit ironoxid, so when the groundwater penetrates these tissue and replacing this with calcite, or silica depending on the temperature it would be no different for filamets depending on the diagenesi taphonomy is rapid as proposed in the paper by mr Vinther wich than since you claim for preservation bias is the case, you have to provide evidence for it simply just saying so does not make it so any citations you can provide to strengthen your argument? 

//I am fully aware of the fact that feathers and reticulae have switched from one to the other in Coelurosauria at least twice,//   Reticulae or is predominantly something that you see in avian birds not general in non dinosaurs. 
 And again if evo devo not have been conducted for the filamets of Yutyrannus how do that automatically correlate to "feathers that would be general apply for many taxas. 

You loophole or oversimplify it  we have 8 different tyrannosaurines from american soil and these asian formations  with scales with no presecence of it of any structures or follicles and to enlight you in a couple of months more are coming for the dorsum and  various parts of the body some from the formations in mongolia wich will be a peer perviewed paper.

How come so many working against the emperical evidence instead of embracing it?  Its been a ongoing problem in world of paleoart. So if you dont accept new data you are doing dogma as we speak.  

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Flishstar In reply to Blomman87 [2018-07-03 14:26:53 +0000 UTC]

My argument was never that they must be filaments. My argument was that they aren't reticulae. Don't put words in my mouth.

I thought it was pretty common knowledge that sandstone is poor for feather preservation, but if you insist:
 Zelenitsky, D. K.; Therrien, F.; Erickson, G. M.; Debuhr, C. L.; Kobayashi, Y.; Eberth, D. A.; Hadfield, F. (2012). "Feathered Non-Avian Dinosaurs from North America Provide Insight into Wing Origins". Science.

Anyways, I am not saying that Tyrannosaurids MUST be feathery. I am saying the current evidence does not indicate they were covered entirely in reticulae, and that without further support the best thing to look at is the integument we see on their ancestors- which happens to be feathers, whether you like it or not.

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Dontknowwhattodraw94 In reply to Flishstar [2018-05-29 21:08:33 +0000 UTC]

Oh I didn't know we had fur from Columbian mammoths...

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Dontknowwhattodraw94 In reply to Migatte [2018-02-12 13:39:44 +0000 UTC]

Exactly.

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Migatte In reply to Dontknowwhattodraw94 [2018-02-12 13:53:25 +0000 UTC]

While there are scale impressions, they are from the thoracic and mid/lower torso regions, which leaves room for speculation in between. Phylogenetic bracketing and physical evidence would tell us that T. rex had feathers from the back of the neck to the top of the back and ending at the base of the tail.

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Dontknowwhattodraw94 In reply to Blomman87 [2018-01-08 15:12:25 +0000 UTC]

I don't understand what you're saying with that first half of your comment.

The 16 or so impressions are small. Give me one reason why an animal that descended from fully feathered ancestors might not have had some sparse remaining feathers here and there as I drew it here, because any large mammal of today that descended from small furry things has them too. (hippos, rhinos, elephants and even some whales)

Feathers and scales do seem to preserve in that formation, but since the we only have three feathered Ornithomimids in a bunch of non-feathered ones then it seems that feathers have a hard time preserving. Also, a giant theropod simply has way less chance of preserving feathers than scales because 1. it's way larger than ostriched-sized Ornithomimids and 2. has way less feathers. It's a miracle that Yutyrannus even has feathers preserved and that one is from the Liaoning formation, a place that has waaaaayyyy better quality in preservation than the Dinosaur Park formation. You see, it's incredibly hard for feathers to fossilise if they're as sparse as I drew them here. It's like expecting a Sumatran rhino or an African elephant to fossilize with impressions of their hairs.

It isn't. 

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Blomman87 In reply to Dontknowwhattodraw94 [2018-01-08 16:22:35 +0000 UTC]

You claimed coined size some of them are up to 11 centimeters in size   leave mammals out of the ocation.

 you also referred to Proceratosauridae being ancestral to Tyrannosauridae : WRONG  they are a sister group and had nothing to interfear with the late tyrannosaurs.      So by your logic: Cause something had feathers in their family tree 40 million years earlier " it cant disapear or morph into something else?

"Give me one reason why an animal that descended from fully feathered ancestors might not have had some sparse remaining feathers here and there as I drew it here" - logical fallicy

in that case, give me a reason why it should be there, because there is no evidence for it and because the relationship between them is not ancestral, but parallel

Yixian has better quality of preservation than Dinosaur Park okey based on what evidence cite your source.

Sry i dont even want to argue with someone taking his own hypothetis to conclude "facts"and go back and learn phylogeny bracket by Brussate and Carr to update yourself.

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Harry-the-Fox In reply to Blomman87 [2018-06-29 08:20:44 +0000 UTC]

As a matter of fact, the evidence suggests the Tyrannosaurids did evolve directly from a feathered ancestor, but underwent a genetic change resulting in their integument evolving into scales.

A process that is not only proven in birds (mainly around their legs), but the actual gene responsible has now been identified.

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Dontknowwhattodraw94 In reply to Blomman87 [2018-01-09 16:57:52 +0000 UTC]

Not really, those on the tail vertebrae are indeed about 50 cm², but that's them summed up as you can see in the picture. The picture clearly shows it's a bunch of small patches kinda close together. On the tail. Where we know some heavily feathered dinosaurs were scaly.

No, I didn't. I said Yutyrannus and Tyrannosaurus share a common ancestor, because Proceratosauridae and more derived Tyrannosauroids (out of which Tyrannosaurids evolved) share a common ancestor. And since we have direct evidence for feathers in Proceratosauridae (like Yutyrannus) but also from more derived Tyrannosauroids (like Dilong) it's safe to speculate that some sparse feathers would still be present on 40 million year later descendants because there's literally no animal today that has lost its ancestral filaments, except for some whales who obviously are not comparable to large terrestrial animals. 
I'm not saying that it can't disappear or morph into something else. I'm saying that the real aswer is that we just don't know about the details and that it's okay to speculate on those. 

I'm not saying it should be there. I'm saying it could be there. I'm also not arguing against a fully scaly Tyrannosaurid. What I'm trying to make clear to you is that sparse filaments are possible and that there's nothing wrong with putting them on a Tyrannosaurid.

The fossils. Literally the fossils. 

That's the thing. I don't conclude facts. All you see here is my personal speculation, based on what the science says and the scientific community. You had a point on Youtube when we were talking about the Tyrannosaurus model of a mainstream documentary that it could've been more conservative even though there was nothing wrong with the things you argued against, but for some reason you came to my deviantart page.
This is a little chart drawn by me. With, again, my personal take on Tyrannosaurids. I'm not saying this is THE only way to do it, but this is my take. And yes, there are speculative features, but there's no science at the moment able to show me I'm wrong. 

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Blomman87 In reply to Dontknowwhattodraw94 [2018-01-10 13:12:25 +0000 UTC]

Actually there is plenty of arguments to prove you wrong www.youtube.com/watch?v=wNQ5hJ… . You said: The filaments wont be able to due to geological problems, Oh one last point - if a harder structure like a filament didnt preserve, then how would the supposively “naked skin” get preserved being a much more softer tissue would that not be odd? 

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Dontknowwhattodraw94 In reply to Blomman87 [2018-01-13 16:21:39 +0000 UTC]

No, I said the chances are smaller if they're spread very sparsely and/or the animal is way bigger.
There is no described naked skin from Tyrannosaurids (if that's what you're talking about). If you're talking about those Ornithomimids and their skin: look at the preserved integuments of the fossil. There's in proportion lots more of it preserved on the animal than any imprint we have from Tyrannosaurids. Conditions were different for the Ornithomimid than for those tyrants. Otherwise we'd have more scale imprints of the latter. phenomena.nationalgeographic.c…

Again, let me repeat myself and make myself very clear: this chart is speculative, but still takes everything into acount of what we know of Tyrannosaurid integument.
The reason why my rex looks like it is drawn here is based directly on Mark Witton's ideas. Just like that guy from that vid based his reconstruction on Carr's: markwitton-com.blogspot.be/201…
The reason why my Albertasaurus is half feathered/half scaley is because I wanted to draw something to show how feathers might have retreated during Tyrannosaurid evolution. 
The reason why my Nanuqsaurus is feathered is based on its size, habitat and climate it lived in because if Tyrannosaurids replaced their feathers with scales because it got too warm, then it only makes sense they'd turn it all around if it got too cold again.

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Blomman87 In reply to Dontknowwhattodraw94 [2018-01-13 20:56:19 +0000 UTC]

Interesting but again you taking your own hypothetis into a scientific discussion can you tell me how you come to the conclusion the conditions were different from the Ornitomimid than those of the "tyrants" 

And what do you mean " this chart is speculative" its based on real evidence fossil integuments conducted by some of the best in the field. 

Mark Witton even said:  although the skin impressions we have show no evidence of such a covering despite preserving tiny integument details,  So by that he is doing the exact thing like you he brings up a theory without backing it up so how can we scientific conclude it was " partial feather when it was no filaments presence at all.

This isn't entirely falsified by the new data" - if there is no evidence for it, then i have all the right to deny its existence

you cannot imply the knowledge existence via absense of proof that it does not exist

its just speculative at most, but its not scientific nor accurate to imply it without relevant data. 

It is just speculations but again you  talking about TYrannosaurids replacing their feathers with scaled because it got too warm and it would make sense they`d turn it all around if it got cold again, can you cite your source of the climate the late tyrannosauridae lived in to scientific conclude this?  

The difference with Carr is that it is scientific concluded and peer perviewed Wittons is not he applies his own theory to existing data to speculate and you jump on the bandwagon because its pretty obvious you like Feathers and dont want to accept what the null hypothetis is about you bringing in your own conclusions and without citing any kind of source i asking you for. 

Now have a nice day. 

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Dontknowwhattodraw94 In reply to Blomman87 [2018-01-13 22:49:40 +0000 UTC]

Because if the conditions were exactly the same you'd get better integument preservation for the Tyrannosaurids, isn't it? You'd get for example way more of tail scales in the Wyrex specimen, you'd get way more of the belly scales of that Albertasaurus etc. It's the same way as it worked for the Ornithomimids: the different specimens didn't have the same quality either. Conditions weren't the same even though they are from the same formation.
What's not to understand about this? Can you show sources that the conditions during the preservation of these theropods were the same? You can't. Nor can I. There are no sources for both of us. 

Because I incorporate everything the literature says, but I speculate about the things the literature can't show. Like a sparse coat of feathers of Tyrannosaurus because we don't have enough imprints to disprove that. Or like my fully feathered Nanuqsaurus, because there is nothing known about its integuments.

That's the thing. There's no conclusion. It's plausible speculation that you can't prove or disprove. The only thing we can say about the Tyrannosaurids we have imprints from is that they were mostly scaled. That's the only certainty. You can't claim they were 100% scaled if you don't have a fully preserved Tyrannosaurid. One can draw one with wing feathers for display, one can draw filaments as eyelashes, one can draw sparse feathers on the body like I did, one can draw a fully scaly one and it would all still be okay because there's nothing against it.

Absence of evidense =/= evidence of absense.
You can choose to not believe in sparse feathers on Tyrannosaurids. Feel free to do so, I won't argue about that, but you can't say sparse feathers definitely weren't there. You need a time machine for that. It's like going to one of my Dromaeosaurid sketches and saying there's no evidence for Deinonychus to have a wattled face because there are no imprints of that and that this means it's inaccurate.
Again: I don't claim this is the thruth. Nor can you claim a completely scaly Tyannosaurid to be the thruth. Nobody can do that. The only thruth is, is that we don't know the complete look of these animals and that some speculation is okay.
You don't seem to know what "accurate" actually means. Accuracy is supported by evidence, inaccuracy is disproven by it. 
Everything that you can't prove or disprove falls under (reasonable) speculation in palaeontology. And some speculative sparse feathers that barely make up 1% percent of an animal's integument of which we know barely half of the total integument is definitely reasonable. Especially if you base it on what you see in modern animals, because you have an existing analogue. You can't call this inaccurate or unscientific. Only speculative, but it's also accurate because everything that the evidence shows is present here and isn't contradicted. There's no one way fits all. There are many paths to take and to still be accurate.
This my point that I'm trying to make all the time.

This study ( pubs.geoscienceworld.org/books… ) has shown that Hell Creek's annual temperature is about 7 to 11° C, which is comparable to Northern Florida IIRC. Only difference is that there were less extremes during the Late Cretaceous which means it didn't get that cold. And for a giant like Tyrannosaurus it makes sense then to loose feathers. It's one of the reasons the Bell et al. study mentioned together with the more open terrain Tyrannosaurus lived in. ( www.researchgate.net/publicati… )
As for the climate of Nauqsaurus: it was comparable to how it is today in Southern Scandinavia, so with freezing temperatures. Makes only sense then for an animal of its size to go back to the extra warmth and insulation of feathers. 

I draw a Tyrannosaurus that is less than 1% feathery and you say I love feathers. Something doesn't work in that conclusion, does it?
Do I have to repeat myself that this chart is speculative? That I'm not saying that this is thé only way of drawing Tyrannosaurids? That I take the scientific data into acount?
I drew a Tyrannosaurus that shows all scale imprints we have as scaley. I drew basically everything else of the body as scaley. Where am I denying the null hypothesis? 

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Blomman87 In reply to Dontknowwhattodraw94 [2018-01-13 23:28:59 +0000 UTC]

Funny thing is that you dont have one real evidence to prove your theory. You throwing all these argument but yet the data is there the fossil, the bones the 16 integuments with no signs of filaments and there before the null hypothetis.    

Nothing wrong with speculations i never said that but the way you provide your evidence or your own agenda to the subject is kinda of interesting.  

So we need a mummified Tyrannosaur to conclude what it really had but in the next sentence we need a time traveling machine to verrify, i see.

No but if we skim through your art we can see a pattern of feathers and by that do i conclude you actually like to paint them with feathers, nothing wrong with that but i dont even know why we keep this conversation up,  i believe in what the data and the best experts in the field is telling us, not by non scientific opinions, that is how i aproach things.  But speculations can be fun i do speculate alot to but i dont imply it on what the actual integuments provide until i am proven wrong from the fossil record. 

I find it very odd that we have 16 and soon more impressions in our disposal from different tyrannosauridae and nothing shows feathers yet people arguing against it like it is something bad instead of happily accept it for what it is, you fall in that category.   Missleading people is common here at DA and  for some reason it is always when it comes down to Tyrannosaurs and their apperance.  

This was my last post. 

Have a nice day.

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Dontknowwhattodraw94 In reply to Blomman87 [2018-01-14 15:44:47 +0000 UTC]

Do you? I can't show you a paper that shows conditions were different during the fossilisation of the specimens we're talking about, neither can you show the opposite. That's the point I'm trying to make.

Then what's the point of coming here and starting a debate? My take is not anymore drastic or shocking than anything else on this site. It's even conservative compared with certain works.

I obviously don't mean those things literally. The bottom line is that we just need a more complete view of the animal's appearance.

The thing is that the scientific conclusions are that these animals were mostly scaley. There's nothing wrong with some sparse feathers. I'm not implying anything. I do put sparse filaments on lots of things, but sometimes also not. Putting filaments on stuff of which we know they had a lot of scales that probably covered the whole body and of which we know ancestral forms had a full covering of feathers is less speculative as those who put lizard-like spikes on the neck and back of Tyrannosaurids, but you don't see anyone argue about that. Get what I'm saying? I get backlash for putting a tiny bit of filaments on an 8 ton scaly theropod without claiming they definitely were there, based on reasonable speculation, but do anything else that doesn't involve feathers and everything stays remarkably quiet. 
I don't know why we keep argueing either, I explained myself comments ago.

I'm not against it. That's the thing. This is the only Tyrannosaurus of me here on DA from after the Bell et al. paper. I have doodles of them without filaments, 100% sclay. I might even upload one with naked teeth and a crocodile face at some point even though the Daspletosaurus horneri paper has recieved quite some scepticism for their arguments about the face covering. Same way that there are so many people here who just like me drew them with lots of fluff in the past, but nowadays keep them sometimes scaley and sometimes put a bit of feathers on it for reasons I explained already. There's nothing misleading about that because nobody claims their reconstruction as fact. There are so many different interpretations of Tyrannosaurid integument online here and that's normal, because there's no conclusive evidence for one particular version. The null hypothesis is there like you said, but it doesn't forbid speculation where the data is missing.

Okay, have a nice day.

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