Wednesday, July 16, 2014

People Think Feathered Dinosaurs Don't Look Scary. They're Right.

This short article on io9 pretty well encapsulates an area of frustration for artists and scientists in the age of feathered theropods.
Ooh, I'm shakin' in my boots.
Photo by Simon Rumblelicensed.
The implication is, right from the title, that it's common knowledge most depictions of feathered T. rex are not cool. Feathered theropods are widely derided by the public because feathers make these scary reptilian monsters less scary. In a recent Facebook discussion, I took one of those "short pelt raptor" images to task for inaccuracy (you know, the kind that pays lip service to the idea of feathered theropods, but with the minimum possible change to the classic silhouette, with a cat-like short pelt rather than a bird-like poof of feathers engulfing the body). In my reply I kind of hypothesized that there's an evolutionary psychology* reason for our aversion to feathered theropods and our cat-like concessions to the idea.

As Andrea Cau has pointed out, paleoartists (myself included), consciously or not, often employ all kinds of subtle tricks to make feathered theropods look "cool". Leaving the face scaly and reptilian is a popular trick; his body might say "Big Bird", but his face tells you he means business. Face fully feathered? Introduce an eagle-like lowered "brow" or some kind of eyebrow analogue so his facial expression can look "mean". Make sure his mouth is open or he's prominently displaying his other weapons in a ninja-like fighting stance. And be sure if you make him colorful, use high contrast, red and black if possible, and light it so his face is in shadow--that way you know he's thinking evil thoughts. This might also allow you to add eye shine making the eyes look like demonic embers! (check back to the io9 article and see how many of these points that T. rex hits).


In the comments to the io9 article, there were the predictable bouts of resistance to the idea that T. rex could have had feathers at all. "It was too large! Large mammals don't have so much fur in hot climates!" The problem with comparisons to large mammals is that feathers are very different in structure from fur, and have very different insulating properties. Fur is mainly used to keep an animal warm, but thanks to the fact that feathers grown in adjustable, planar layers, and are better at trapping and regulating air flow, many large birds use their feathers to very effectively keep themselves cool by circulation while blocking the skin from absorbing direct sun. It may actually have been disadvantageous for a large animal to lose its feathers, especially if it lived in a hot sunny climate. The fully-feathered Yutyrannus was not significantly smaller than any but the largest T. rex. Most T. rex specimens fell short of the 6.8 tons estimated for the most gargantuan known adults like Sue, that is certainly not the species average size!


But, there was one comment that played right into my ego-psych hypothesis. The commenter basically stated that we know juvenile T. rex had feathers, but there's no reason to think adults kept them. Except even that premise is wrong. 
There is in fact zero direct evidence to support the hypothesis that T. rex juveniles had feathers, let alone that they had them and then lost them. It's simply easier for people to assume that a baby animal, which is supposed to be cute, had feathers, which we psychologically associate with cute animals. 

Are one of these things is not as scary as the other?
Illustrations by M. Martyniuk, all rights reserved.

It is actually less of a stretch (i.e. more parsimonious) to hypothesize that based on its phylogenetic bracket, T. rex had feathers and retained them throughout its life, than the hypothesis that T. rex was born with feathers, lost them because they became disadvantageous at some unspecified weight, then through some unknown developmental pathway replaced its feathers with the kind of thick, scaly skin it is usually depicted with and would need to protect itself from the sun/injury if it lacked feathers. But this convoluted thinking is easier for people to accept because T. rex is the king of all monsters, and monsters are by definition not cute.**

The sad fact is, T. rex may not have looked all that cool. I think John Conway and others have brought this up before. It, and many if not most other dinosaurs, may very well have looked really, really stupid to us. Nature doesn't care if an animal looks intimidating to a species that evolved 66 million years later in a completely different environmental context alongside a vastly different set of predators. Our brains are programmed to find mammalian and reptilian predators scary at least in part* because we evolved alongside these and our survival depended on it. We had no such pressure for most kinds of birds***, and maybe coincidentally, we find very few kinds of birds the least bit intimidating. We have to be told/shown that a cassowary is even capable of being dangerous, and people still constantly trot this out as a surprising fact, despite the fact that it has very few physical differences from a Velociraptor, other than being much larger


So, if your average Joe met a non-avialan theropod in real life, the reaction might be less like any of the raptor scenes in the original Jurassic Park and more like Newman vs. the cute, colorful, silly, hopping (read: bird-like) dilophosaur - bemusement leading to injury.

* I know evo psych is mostly made up of untestable just-so-storys. But it's still fun to think about.


** That's sarcasm. Tyrannosaurs were not monsters, they were plain old regular animals. A lesson people forget from the original Jurassic Park (probably because they're not actually depicted hat way in the movie, despite the fact that the characters talk about it).


***Raptors seem to be the exception. Probably because they preyed on early humans, and maybe also because of their mean-looking "eyebrows"?


32 comments:

  1. In an old Theropoda.blog post on dromaeosaurid feathers, a commenter suggested that big eudromaeosaurs were featherless - at least when adults - following the "idea" that feathers are for a birdy lifestyle and adult raptors were too big for such lifestyle. Apart from the nonsense, I replied that in birds, adults are always more feathered than juveniles and that we had no reason to think otherwise for dromaeosaurs. Similicaudipteryx then has showed that this is probably a pattern shared by all chaoouiaouinianoaeans... err, pennaraptorans. I suspect one reason to reject feathers in theropods is anthropomorphic heroism: many considers theropods as sort of human heroic characters (being predatory and bipedal like us is probably the reason: and the various Jurassic Fights on documentaries and forums confirm this idea), and nobody likes a hero dressed like a bird.
    Furthermore, probably many consider feathers as a sort of "dress" with the "animal" as just the body under that dress. The idea that feathers are a fundamental part of the animals bearing them, as any other organ of the body, is hard to be accepted...

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  2. Andrea, I think you nailed it with the anthropomorphic hero idea. Even with eagles it's played as a joke... https://www.youtube.com/watch?v=VeIumG1cliI

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  3. Perhaps, for English-speaking people, are "scary" and "scaly" somehow linked... so, if a feathered theropod is not scaly than it is not scary? ;-P

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  4. Indeed, are there any mammals whose young are furry but whose adults are naked? Some seals are the only example I can think of. And even then, growing up just involves losing the fur, not replacing it with something else.

    But don't we have a couple of scaly skin impressions from large tyrannosaurs?

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    1. Its from the leg area which even in modern birds is either scaly or bare.

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    2. Its from the leg area which even in modern birds is either scaly or bare.

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  5. The cassowary you use as an example of a "not scary" theropod even has a dark, unfeathered face, a lowered brow, and some red/black contrast on its body.

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  6. "The problem with comparisons to large mammals is that feathers are very different in structure from fur, and have very different insulating properties. Fur is mainly used to keep an animal warm, but thanks to the fact that feathers grown in adjustable, planar layers, and are better at trapping and regulating air flow, many large birds use their feathers to very effectively keep themselves cool by circulation while blocking the skin from absorbing direct sun. It may actually have been disadvantageous for a large animal to lose its feathers, especially if it lived in a hot sunny climate"
    Just a suggestion: you should write more about it. A lot of people write such critics about dinosaurian integument without knowing feathers' properties and even paleo-enthusiasts (myself included) know very little about the subject.
    This post is a great read, but a more technical one would be a really nice addition.
    Neveretheless, fantastic article as usual.

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  7. I don't know, Matthew-- as a falconer for all my life who has seen the Central Asian Kazakhs hunting foxes with Golden eagles (and they catch much bigger prey) I have never had a hard time finding (some) birds scary. John McLoughlin depicted very eagle- like "raptors" in his science fiction novel The Helix and the Sword way back in 1983; I have always considered him second only to Ostrom and Bakker in bringing the idea of feathered Dinos to the public of that time, at least the public seriously interested in science.

    Your Field Guide is my new favorite tool-- I love to show the plates of feathered Dromaeosaurids to people who still think "big lizard".

    And I second "Elijah's" request: more technical material like that counterintuitive analysis of feathers and cooling.

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  8. I'm pretty sure the evidence is pointing toward scaly tyrannosaurids--Wyrex and other unpublished specimens supposedly show scales, and featheriness/scaliness seems to have been fairly labile in ornithodires. Unless shown otherwise, it seems likely that tyrannosaurids either were scaly, had fine filaments between their scales like Juravenator, or looked like tenacious awesomebro attempts to draw a feathered velociraptor. I'm really hoping not the last one.
    Since you point out the weirdness of the ontogenetic thing (now that you mention it, does that even happen in anything today?) it seems likely that tyrannosaurids (but not basal tyrannosauroids) were primarily scaly at all ontogenetic stages. Not sure what the implications of Sciurumimus are for this.
    When it comes up, I try to convince people accepting feathered dinosaurs doesn't mean they have to give up on cool dinosaurs--I think the latter isn't really possible to argue against, so I might as well try and convince people of scientifically-accurate awesomebro raptors over the bipedal death lizards Jurassic Park created.

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  9. Great post - though I'm not entirely convinced by your line of thinking.

    I keep noticing something of an opposite fallacy - some people in paleontology and paleoart put so much undue weight on phylogenetic relationships that they completely discard environmental pressures (i.e. animals occupying similar niches evolving convergent features which don't exist in their close relatives). Perhaps I'm biased because my background is in linguists, and this kind of thing happens way too often in the debates about origins of language (speaking of which, great post on bird calls days ago).

    I was actually quite enthusiastic for feathered tyrannosaurs, but after reading up on late Cretaceous climate, I somehow gave in to the 'too large for feathers' argument. On the other hand, I also had an issue imagining what a 'partially feathered' or 'temporarily feathered' animal might have looked like. Fur is simply inherently more 'gradable'. Does your argument on thermoregulation concern 'modern' feathers, or the more basal form tyrannosaurids might have had? And is it okay if I hope some day we'll get direct evidence pointing us one or the other way in the debate?

    As for 'scariness'... The closest living resemblance of a T.rex-shaped skull I can think of is the broad-snouted caiman - and I wouldn't say they don't look scary (though perhaps a little funny). The rest of the tyrannosaur may have looked weird, but I'd still say a homo sapiens sent back in time to the late Cretaceous might freak out upon seeing the front of its head.

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    1. I was also convinced by the "too large for feathers" argument, until I learned that Yutyrannus were extensively feathered despite living in temperatures of around 10°C (Amiot et al. 2011). T. rex lived in similar temperatures of around 7-11°C (Arens & Allen 2014).

      As for imagining what a "partially feathered" animal might have looked like, ostriches are a good extant example in terms of feather distribution. There's also this great rendition (http://tomozaurus.deviantart.com/art/Tyrannosaurus-2014-438953910) of a partially feathered individual of T. rex by Tom Parker that might help you imagine what it might have looked like.

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    2. Thanks for bringing up the temperature issue and the references, that's very interesting. So far I've been under the impression that the climate in Early Cretaceous Northern China would have been much colder than Montana in the Maastrichtian (on the other hand, T. rex fossils have also been found much further south).

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  10. One more comment, if I may...

    >[...] the hypothesis that T. rex was born with feathers, lost them because they became disadvantageous at some unspecified weight, then through some unknown developmental pathway replaced its feathers with the kind of thick, scaly skin it is usually depicted with and would need to protect itself from the sun/injury if it lacked feathers. But this convoluted thinking is easier for people to accept because T. rex is the king of all monsters, and monsters are by definition not cute.

    Thing is, if it turns out there's evidence T. rex actually had scales (and assumingdinosaur suggests there is), then this 'convoluted' solution may actually be more likely than the non-convoluted one. When evolution makes quick and dirty changes, it very often protracts them into early adulthood (chickens are born with teeth, etc.). Bonus points if the changes involved are due to size or adaptations only an adult animal would possibly have use for.

    Perhaps I'm completely wrong - all I mean to say is that I can see some logic in arguments which you ascribe to just 'people still want T.rex to look badass'. I also agree with Elijah - I'd love to hear more about how feathers differ from fur and about their development.

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  11. Grant: "Indeed, are there any mammals whose young are furry but whose adults are naked?"

    There are elephants ("Young elephants are hairier than adults and their hair is reddish-brown in color. As they mature, the amount of hair is reduced and becomes darker": http://seaworld.org/animal-info/animal-infobooks/elephants/physical-characteristics/ ), but your point still stands.

    "But don't we have a couple of scaly skin impressions from large tyrannosaurs?"

    Yes: See the Switek quote, which sums up my opinion on the matter until new evidence shows otherwise.

    Matthew Martyniuk: "Feathered theropods are widely derided by the public because feathers make these scary reptilian monsters less scary."

    I figured that had something to do w/the "Reptiles Are Abhorrent" trope ( http://tvtropes.org/pmwiki/pmwiki.php/Main/ReptilesAreAbhorrent ).

    "Face fully feathered? Introduce an eagle-like lowered "brow" or some kind of eyebrow analogue so his facial expression can look "mean"."

    Wouldn't eagle-like brows make more sense on faces that aren't fully feathered ("The facial feathers of raptors tend to be simplified to bristles and semibristles, which are easier to keep clean than are fully vaned feathers": http://books.google.com/books?id=zM0tG5ApO0UC&pg=PA88&dq=%22feathers+of+raptors+tend%22&hl=en&sa=X&ei=WvHHU6GYBfXfsASouICACA&ved=0CC4Q6AEwAA#v=onepage&q=%22feathers%20of%20raptors%20tend%22&f=false )? Or am I misinterpreting what you meant by "fully feathered"?

    BTW, I too would like see a Dinogoss article about feathers & cooling. More specifically, I'm curious about whether hair-like proto-feathers acted more like true feathers or fur in that sense.

    -Hadiaz

    Quoting Switek ( http://www.nature.com/news/palaeontology-the-truth-about-t-rex-1.13988 ): "Thomas Carr, a palaeontologist at Carthage College in Kenosha, Wisconsin, argues, for example, that unpublished fossils with skin impressions from close relatives of T. rex show scaly skin. These findings suggest that even though some earlier tyrannosauroids had feathers, the subgroup called tyrannosauridae (which includes T. rex), seems to have undergone an evolutionary reversal from fuzz to scales."

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  12. Good drop on the quote there, Hadiaz. I'm tempted to side with Carr on this one. What *limited direct evidence we do have to that effect points away from the tyrannosaurids having feathers, or at least being coated with them as shown in this post.

    Contrary to Switek, Peter Larson's Wyrex shows patches of scaly skin, while he attests of similar findings on a nearly complete specimen of Nanotyrannus (I admit I've lost all trace of the "Dueling Dinosaurs find since it was auctioned in November, so I'm a bit unsure as to the status of that particular specimen). I've also heard rumors of strips of scaly skin being collected along with Casper College's "Lee Rex," but that fossil is still being prepped. Not peer-reviewed findings to be sure, but if we're in the business of putting T. rex in full coats of dinofuzz, it seems a bit odd to get to scholarly when it comes to evidence.

    If anything, it seems that the evidence points to any such tyrannosaurid integument being limited to display structures only, which I admit, could look pretty scary. Pull up any ancient or depiction of a dragon from any corner of the world and you'll almost always find them shown with intimidating crests or manes or something.

    But as much as I'd love to jump on the feathered tyrannosaur bandwagon, there's one thing about the fuzzier, "chickany," T. rex hypothesis I notice almost never gets brought up. How on earth would such an animal keep itself clean? The biggest modern birds we have today are still small and flexible enough to be able to constantly preen themselves of ticks, lice and other parasites. But I find it hard to imagine an animal the size of a tyrannosaur being able to groom itself in the necessary manner. These were animals that lived on and around bleeding carcasses and lead violent, injury-prone lives. An open wound or a messy dinner could leave any feathers covered in blood, flesh, and tissue that would fester and become a haven for disease. Extant birds like vultures that carry on similar lives have tended to lose their feathers for just such a reason. Plunging your head into a bloody carcass for a living seems to be a surefire way to end up with a colony of bacteria swarming around your face and neck for a feathered animal. Not a great lifestyle choice.

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    1. "Good drop on the quote there, Hadiaz."

      Thanks.

      "Contrary to Switek, Peter Larson's Wyrex shows patches of scaly skin,"

      What I don't get is why Switek ignores Wyrex's scaly skin whenever the issue of feathered tyrannosaurs comes up? I mean, ppl have known about it since at least 2008 ( http://books.google.com/books?id=5WH9RnfKco4C&pg=PA47&dq=%22skin+with+wyrex%22&hl=en&sa=X&ei=Tf3HU4SeEOLNsQSJ5YL4Cg&ved=0CB4Q6AEwAA#v=onepage&q=%22skin%20with%20wyrex%22&f=false ).

      "I admit I've lost all trace of the "Dueling Dinosaurs find since it was auctioned in November, so I'm a bit unsure as to the status of that particular specimen"

      Last I heard, the find "failed to sell when they went under the hammer in here Tuesday (Nov. 19), despite projections that they would break auction records...Auction house officials said they are hopeful the dinosaur duo will find a home and are now entering into negotiations with interested U.S. institutions" ( http://www.livescience.com/41325-dueling-dinosaur-fossils-fail-to-sell-auction.html ).

      -Hadiaz

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    2. "What I don't get is why Switek ignores Wyrex's scaly skin whenever the issue of feathered tyrannosaurs comes up? I mean, ppl have known about it since at least 2008"

      Make that 2004 ( http://www.unearthingtrex.com/pages/journal_dailyjournal.html ).

      -Hadiaz

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  13. Thanks for the comments everyone! In regards to the Wyrex scaly skin, the good folks over at Hell Creek Forum have compiled an exhaustive list of every report of skin impressions and whatever we can glean about their structure, since virtually all are un- or barely published on.

    Gorgosaurus or Albertosaurus: impression/s showing "smooth naked skin lacking the scales of other dinosaurs" [Mentioned in talk by Currie, 2001 at the A. Watson Armour Symposium: The Paleobiology and Phylogenetics of Large Theropods]; at least one of these impressions shows sparse, fine rounded scales and is from the tail. [Mentioned in book Encyclopedia of Dinosaurs]

    Tarbosaurus: Skin impressions showing reticula in a footprint assigned to Tarbosaurus from the Nemegt Formation. [Published: Currie et al., 2003 "The first Late Cretaceous footprints from the Nemegt Locality in the Gobi of Mongolia"] A small patch of scales was known on a specimen too damaged to know the locality of the impression. [Mentioned in article by Currie in 2003] Undescribed naked skin from a badly weathered skull forming "wattle or bag of skin" under the throat are apparently known. [Pers. comm. by Konstantin Mikhailov via Ken Carpenter in books Eggs, Nests, and Baby Dinosaurs and Encyclopedia of Dinosaurs]

    Tyrannosaurus: Patches of skin on the underside of the tail on BHI 6230 showing tiny bumps between 1 and 2 mm wide. Larson describes the patches as very small. [Mentioned in book Tyrannosaurus rex: The Tyrant King] Sereno mentions that he has the specimen in his lab and that it lacks true scales, and suggests that these areas could have bore feathers in life. [Pers. comm. in an interview] Undescribed palm-sized patch found with a rib and caudal vertebrae showing "bird-like" naked skin likened by Detrich and Currie to a plucked chicken or an elephant's hide. [Pers. comm. by Alan Detrich and Philip Currie via the DML]

    Here are some photos of supposed T. rex skin fossils:
    http://www.fossilking.net/CurrentDigFolder/t_rex_9_01/rex_04.jpg
    http://www.fossilking.net/CurrentDigFolder/t_rex_9_01/rex_05.jpg

    The upshot seems to be that while typical dinosaurian reticulate scales have been reported, they are either from an unknown portion of the body and/or at or near the leg and underside of the tail. Where skin has been found from elsewhere on the body, it has been described as "naked" or with a "plucked chicken" appearance, as visible in the photos. So no, it is not correct to say that we know for a fact tyrannosaurids had ONLY scales. Scales have only been found from portions of the body where we'd expect them (hind limb), and even then their exact position is unknown.

    I'm very curious to see when and if Sereno publishes his supposed "plucked chicken skin" specimens...

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    1. (Here's the photo source article http://www.fossilking.net/CurrentDigFolder/AP_article.html)

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    2. "Gorgosaurus or Albertosaurus: impression/s showing "smooth naked skin lacking the scales of other dinosaurs" [Mentioned in talk by Currie, 2001 at the A. Watson Armour Symposium: The Paleobiology and Phylogenetics of Large Theropods];"

      I read that Currie's original interpretation was exaggerated & that the impressions "do have mosaic scales, but these are smaller than those on typical hadrosaurid or ceratopsid skin" ( http://dml.cmnh.org/2001Jul/msg00243.html ). Is that what the encyclopedia is referring to?

      "Sereno mentions that he has the specimen in his lab and that it lacks true scales, and suggests that these areas could have bore feathers in life. [Pers. comm. in an interview]"

      Is Sereno referring to Wyrex &, if so, how are these impressions not of "true scales"?
      http://i1242.photobucket.com/albums/gg522/amargasaurus/skin1_zpse1132ff1.jpg
      http://4.bp.blogspot.com/-BsMK7Rz0kOY/UY5XGHsmdmI/AAAAAAAABME/yuXx0Q1mCKU/s1600/img010_wyrex.jpg

      -Hadiaz

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    3. Good question! We'll never know until they're described. Another good question is, can we even tell the difference between scales and textured naked skin based on fossil imprints? And if so, how?

      Here's a bit of skin from a rhino. If all we had was a palm-sized mould fossil, would we be able to differentiate this from tuburculate scales?

      http://image.shutterstock.com/display_pic_with_logo/671950/107022044/stock-photo-close-up-of-black-rhinoceros-diceros-bicornis-skin-texture-107022044.jpg

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    4. Now that you mention it, are there any non-hairy rhino skin impressions that can be used as a basis for comparison vs. both the Wyrex skin impressions & definitely scaly skin impressions?

      -Hadiaz

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    5. I definitely agree, scaly tyrannosaurs are a far from definite thing--however, I think that there is pretty good reason to believe that, unless Sereno has something particularly impressive up his sleeve (which frankly wouldn't surprise me--isn't he sitting on pretty good Spinosaurus and noasaur fossils?), the burden of proof is still on feathers, not scales. Unless proven otherwise, I'm picturing a fuzzier-than-average elephant at most for tyrannosaurid integument.
      When it comes to reconstructions, at least, rhino skin and scales aren't too different. Both would look "scaly" up close and wrinkled or smooth at a distance.

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  14. I believe this (http://log.johnconway.co/post/46259087381/jurassic-park-4-awesomebro) was the post where John Conway brought up similar sentiments.
    Also, vis-a-vis the role of feathers in thermoregulation, I have heard that only the advanced stage of feathers seen in birds today had such versatility. I also heard that the feathers that tyrannosauroids had may have been too primitive to exhibit such versatility. Is this not the case?

    Also, can I have the link to the Facebook discussion you mentioned in the article? I also feel some distaste for "short pelt raptor" reconstructions and would like to see your thoughts on them.

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  15. I think I must be an exception to this trend. I think feathered dinosaurs are a lot cooler than non-feathered dinosaurs. Perhaps it's because I don't like monsters, anyway. I like animals that are cute and deadly at the same time. And feathered dinosaurs fit that description very well. And maybe another reason why I like them is because, throughout history, humans have always thought of birds as being passive, harmless creatures.

    For some reason, I have a recurring image in my mind of Robin Thicke (an American singer) encountering a feathered dinosaur and exclaiming "What is this thing? A bird trying to be a dog?", before being mauled to death. I don't hate Robin Thicke, and I don't want him to die. I'm also not a raging psychopath who enjoys killing or anything like that. But the idea of a feathered dinosaur attacking a human just appeals to me, for some reason. And there's something about Robin Thicke that makes it especially fun to imagine that he's being attacked by a dinosaur. I can't really describe it using words. It's a combination of his eyes, his hair, facial features, and his body shape, the sound of his voice, and his physical mannerisms. He just has a certain indefinable quality that makes it seem like he has "I WOULD MAKE A PERFECT DINOSAUR ATTACK VICTIM" written all over him.

    And guess what? I don't even have any idea what I'm talking about anymore. Maybe I'm just crazy.

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  16. I agree, actually; if Jurassic Park is ever rebooted, the raptors' first human victim would reach out to pet it before it pins him/her down with its claws and begins to eat him/her while he/she is still alive.

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  17. Here's what Phillip had to say about my t.rex skin found with a cervical vertebra:
    http://www.fossilking.net/CurrentDigFolder/t_rex_9_01/rex_04.jpg
    http://www.fossilking.net/CurrentDigFolder/t_rex_9_01/rex_05.jpg

    Royal Tyrrell Museum PO Box 7500 Telephone 403/823-7707
    of Palaeontology Drumheller, Alberta Fax 403/823-7131
    Canada TOJ oYo www.tyrrellmuseum.com
    Robert Detrich
    Detrich Fossil Company
    P.O. Box 1313
    Wichita,
    67211 U.S.A.
    February ll, 2002
    Dear Robert:
    Here are the impressions back with no clear decision. I
    compared them with the impressions of tyrannosaur skin that
    we have, and each tubercle/scale is slightly bigger and more
    pronounced than on our skin. The shape of each tubercle/scale
    on the piece you sent is also more radially symmetrical,
    whereas ours is peaked towards one edge. My first impression
    was that the pieces you sent are actually the infilling of
    the surface texture of a trionychid turtle. However, looking
    at them under the microscope suggests that the surface was in
    contact with sediment rather than bone. Furthermore, the
    undulating surface doesn’t match the turtle shell theory (I
    would expect a natural mould should follow the almost flat
    gentle curved surface of the turtle shell, although of course
    the original turtle shell might be distorted). In short, I
    don’t knowm It might be tyrannosaurid skin, but it is c
    different from the patches that we have.
    Cheers, Philip

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  18. Great idea for up-cycling! This would be good to do after a party. I wonder what kinds of flowers you could make with forks and knives too.
    cara mengobati kurap di selangkangan

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  19. most of featherhead dinosaurs from china

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