Diversity: Feathered Vs Non-Feathered?

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Diversity: Feathered Vs Non-Feathered?

Postby GlaciusTS » Wed May 08, 2013 10:53 pm

So it has been proven that T-Rex was an opportunist and behaved as both a scavenger, and a predator (when the prey was somewhat small and not too difficult to obtain). We have learned quite a few things in the past about dinosaurs, that's for sure. But what many people don't consider is when they changed. Now, I know a few basic things about dinosaurs, but I'm not entirely familiar with every aspect of their history.

What species of dinosaur had feathers? And at which point in evolution did they accumulate these feathers? Obviously one species didn't become another overnight. Many people I've spoken with argue quite specifically about a species they've read about, but don't consider that specimens discovered have often been found looking fairly different from others of the same or at least very similar species. It's highly possible that their deaths had been separated by many years of evolution, so vague changes in anatomy have likely been documented. At which point did reptiles obtain feathers? Did a dinosaur inherit feathers from an ancestor species? Or did they acquire feathers themselves at some point in their own stages of evolution?

This is definitely a question for the experts among you. I'm am well aware that many species had feathers, but at which point did they acquire them? Did they all have feathers at one point or did bald members of a species exist with feathered members? Maybe some members of a species had very few feathers, while feathers were more abundant on others?

If we do not know for sure, perhaps this could be implemented in the game for the sake of diversity? I'm not an expert on the subject, so i am legitimately asking this as a question to those of you who know more than me on the subject. Educate those of us who may not know the specifics. Do we know for certain when a species or it's ancestors first adopted feathers? If you're unsure, is it possible that perhaps the whole reason we didn't discover feathers until recently, is because some discovered specimens did not have evidence of feathers? When I think about how many specimens have been discovered, there's a good chance many of them HAD been separated from many years of evolution and have looked someone different from one another, despite all being considered a variant of T-Rex or Velociraptor. There could be huge gaping holes in my logic, but it would just seem weird to ignore that the dinosaurs are the missing link between reptiles and birds, so there had to be a point that certain members of a species had feathers and others didn't. Whether it was a variant of the Velociraptor itself, or one of it's ancestors.

Please understand, I'm not trying to start an argument here. I'd just like to become better educated on the matter, and i'm considering the possibility that there may have been variants of different species that could add even more diversity into the game. I'm sure we all like diversity, right? If i'm wrong, by all means let me know and I'll gladly admit it. I'm just wondering if adding both feathered and bald variants could add some easy diversity to the game, just like patterns and color variants. Alternate coloring and patterns, as well as adding or removing feathers is an easy way of adding diversity to the game. That way you don't have to create whole new set of models for a bunch of different dinosaurs to add variety.

Think about it, would you rather 15 types of dinosaur with 1 color scheme each? Or 12 types with 2-4 variants each?

To the experts among us, what possibilities are we looking at? And if science hasn't proven yet at what point a species adopted feathers, or other comparatively recent discovered traits for that matter, do you think it is acceptable to consider the possibility that bald variants did exist? Would it be okay to you if the game included bald variants?

(Sorry for the text wall guys, just being thorough.)
Last edited by GlaciusTS on Wed May 08, 2013 10:59 pm, edited 1 time in total.
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Re: Diversity: Feathered Vs Non-Feathered?

Postby Pangea » Wed May 08, 2013 10:55 pm

Basically, the entire coelurosaur (Tyrannosaurs, Raptors, Oviraptorids, Compsognathids, Troodonts, Therizinosaurs, and Ornithomimosaurs) group had feathers. The only ones that had modern feathers were raptors, ovis, troos, and possibly ornis. The rest had protofeathers.

This is applies for all raptors.

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Re: Diversity: Feathered Vs Non-Feathered?

Postby The Thagomizer » Wed May 08, 2013 11:18 pm

GlaciusTS wrote:So it has been proven that T-Rex was an opportunist and behaved as both a scavenger, and a predator (when the prey was somewhat small and not too difficult to obtain). We have learned quite a few things in the past about dinosaurs, that's for sure. But what many people don't consider is when they changed. Now, I know a few basic things about dinosaurs, but I'm not entirely familiar with every aspect of their history.

... Not sure what you are talking about. Many pieces of evidence in many different area strongly support the idea that Tyrannosaurus as adults were competent macropredators who would've taken contemporary Edmontosaurus, Triceratops, and possibly even young Alamosaurus as prey. I couldn't tell you of any current experts who seriously believe that Tyrannosaurus were incompetent hunters or anything like that. Indeed the man who first suggested the idea, Jack Horner, later admitted that he posited the whole "Tyrannosaurus as scavenger" hypothesis to prove a point; people had assumed Tyrannosaurus was a predator without actually looking into it. Horner wanted to point to people that you can't just make an assumption as scientific fact, you have to do the research first. Starting this debate was a good way to make that happen, as people scrambled to prove what they already knew, essentially.

However, now that the research is done, the debate is long over; we know Tyrannosaurus was quite a capable predator of large prey.

The feather questions are difficult ones, which I will try and answer when I get back to my computer later tonight.
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Re: Diversity: Feathered Vs Non-Feathered?

Postby GlaciusTS » Wed May 08, 2013 11:32 pm

Pangea wrote:Basically, the entire coelurosaur (Tyrannosaurs, Raptors, Oviraptorids, Compsognathids, Troodonts, Therizinosaurs, and Ornithomimosaurs) group had feathers. The only ones that had modern feathers were raptors, ovis, troos, and possibly ornis. The rest had protofeathers.


Is there any evidence as to when Coelurosaurs acquired feathers? A common ancestor perhaps? Is it possible that some members of a species shed their feathers for periods or lost them? I find it pretty intriguing. I know birds of today all have feathers, I'm pretty sure there are no exceptions, but I know they moult, and some species have less noticable feathers. I'm unfamiliar to the anatomical specifics and purposes of protofeathers. I don't mean to pry with questions, you may not have answers for them all. I'm just thinking of the possibility that some Coelurosaur may have been exceptions to the rule, similar to how many current species have evolved with minor exceptions. Some members of a species can appear bald (maybe having whiskers or very short unnoticable fuzz) such as hairless coyote and members of the cat family while very close relatives or alternative breeds of an animal can be very furry. Or perhaps during early stages, a species who had previous began to grow feathers may have migrated and evntually lost the need for them? To shorten the question, Is there any evidence, either proving or disproving, that some members of Coelosaur may have either been bald or at least appeared bald?
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Re: Diversity: Feathered Vs Non-Feathered?

Postby Pangea » Wed May 08, 2013 11:37 pm

Common ancestor's most likely. The best guess are either a basal coelurosaur, or... Well, this thing.

It's called Sciurumimus.

There's people who have been speculating that it may be a megalosaur, indicating it may be a theropod trait. Or course, there's also the possibility that it's a compsognathid, since it's a baby, and there's skin impressions of non-coelurosaur theropods already, namely Allosaurus, Carnotaurus, and Concavenator, that show scales. So... You be the judge.
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Re: Diversity: Feathered Vs Non-Feathered?

Postby Atouk » Wed May 08, 2013 11:41 pm

I don't like to nitpick, but it is also conceivable that species of dinosaurs that had feathers and proto-feathers were showing signs of juvenile dinosaurs or dinosaurs in mating season or some other "sometimes" circumstance, maybe even gender-specific. We just don't know. But some had them.
As for Tyrannosaurus Rex, what carnivore doesn't like a conveniently provided, pre-killed meal? IMHO it is ludicrous to say that he/she was either predator or scavenger; almost certainly he must have been both.
However, in light of the scenario in this game, I wouldn't even frown at tail-draggers and lake-dwelling brontosaurs, because this is more in the light of a dino movie than history. The carnivores should be big and scary and bloodthirsty, while the others should fill their roles: ceratopsians and stegosaurs, etc. should stand their ground and fight (and charge people), while the sauropods should probably act like big cows. While on the subject, the Devs should look back to the paintings of Charles Knight for inspiration! However, I suppose they are wanting to avoid the poo-pooers who want to ...nitpick! ;)
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Re: Diversity: Feathered Vs Non-Feathered?

Postby Pangea » Wed May 08, 2013 11:42 pm

Actually, the devs are willing to go forward with science. They even mentioned a feather design initially. BEFORE the rex was revealed.
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Re: Diversity: Feathered Vs Non-Feathered?

Postby inc_B » Thu May 09, 2013 2:08 am

GlaciusTS wrote:
Pangea wrote:Basically, the entire coelurosaur (Tyrannosaurs, Raptors, Oviraptorids, Compsognathids, Troodonts, Therizinosaurs, and Ornithomimosaurs) group had feathers. The only ones that had modern feathers were raptors, ovis, troos, and possibly ornis. The rest had protofeathers.


Is there any evidence as to when Coelurosaurs acquired feathers? A common ancestor perhaps? Is it possible that some members of a species shed their feathers for periods or lost them?


Not exactly what you're asking, but genes related to feathers have been found in crocodilians (alligators in particular, I think). This means that feathers could have turned up in any of the dinosaurs - even the sauropods. And possibly turtles, which I would pay money to see.
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Re: Diversity: Feathered Vs Non-Feathered?

Postby The Thagomizer » Thu May 09, 2013 2:39 am

Atouk wrote:As for Tyrannosaurus Rex, what carnivore doesn't like a conveniently provided, pre-killed meal? IMHO it is ludicrous to say that he/she was either predator or scavenger; almost certainly he must have been both.

Absolutely! It is more than likely that Tyrannosaurus was an opportunistic feeder who would've taken any meal it could get. I was merely in my last post defending the idea that Tyrannosaurus would have been no slouch when it came to preying on other large animals.

GlaciusTS wrote:Is there any evidence as to when Coelurosaurs acquired feathers? A common ancestor perhaps? Is it possible that some members of a species shed their feathers for periods or lost them? I find it pretty intriguing. I know birds of today all have feathers, I'm pretty sure there are no exceptions, but I know they moult, and some species have less noticable feathers. I'm unfamiliar to the anatomical specifics and purposes of protofeathers. I don't mean to pry with questions, you may not have answers for them all. I'm just thinking of the possibility that some Coelurosaur may have been exceptions to the rule, similar to how many current species have evolved with minor exceptions. Some members of a species can appear bald (maybe having whiskers or very short unnoticable fuzz) such as hairless coyote and members of the cat family while very close relatives or alternative breeds of an animal can be very furry. Or perhaps during early stages, a species who had previous began to grow feathers may have migrated and evntually lost the need for them? To shorten the question, Is there any evidence, either proving or disproving, that some members of Coelosaur may have either been bald or at least appeared bald?

The short answer is yes, it is possible that some Coelurosaurs may have been bald. Skin imprints from the Compsognathid Juravenator as well as imprints from some Tyrannosaurids show that at least some Coelurosaurs had some scales somewhere on their body.

However, we should not consider naturally bald Coelurosaurs as scientifically sound until direct physical evidence proves such a thing existed. This is the most parsimonious assumption based on what evidence is available to us. Since we have evidence that the earliest members of Coelurosauria had feathers, and that later members (such as birds and Yutyrannus) retained most of their feathers, it is safe to assume that all the 'in-between' animals likely had at least some feathers as well, until we can prove otherwise. It also helps that we have no examples at all of modern birds who have lost all their feathers, and thus we have no examples to show that losing one's feathers all over the body would prove advantageous. We do have birds that have grown 'bald spots', like Ostrich thighs and vulture heads, but full feather loss has never been documented outside of cases of selective breeding or strange diseases.

Perhaps this sounds like a lot of assumption-making and speculation, and it is, but really, this line of reasoning (called Phylogenetic Bracketing) is also what the experts have used to determine that Dinosaurs had hearts. Think about it, hearts don't fossilize, so we technically have no direct evidence that nonavian Dinosaurs had them. However, the fact that birds, and all other vertebrates for that matter, have hearts makes it safe to assume that Dinosaurs had them as well.

So in summary, while it is possible that bald Coelurosaurs eixisted at some point, the existence of such an animal is not supported by what evidence we currently have.


As for the origins of feathers, you are asking questions that the experts are still trying to figure out. If we use the same logic used above, we can actually assume that the ancestor of all Dinosaurs had feather-like structures. I made a post discussing this subject on another website (in response to a question about why Dilophosaurus would mot likely have had quill-like integument), and will quote that here in the hopes that it proves useful in answering your questions.

On the Primal Carnage Forums, I wrote:We've known for quite a long time that Coelurosauria had feathers. Birds, Deinonychosaurs, Tyrannosauroidea, the like. But for a while, we had no evidence to prove that feathers - or even more basal feather-like structures - existed anywhere on the Dinosaur family tree outside of Coelurosauria.

Imagine our surprise when Otto the Sciurumimus came to light. This small Theropod was beautifully preserved with what is clearly a coat of fuzz. Thanks to the wealth of discoveries made in the Yixian Formation, a small Theropod Dinosaur found with a coat of 'protofeather' fuzz is nothing new at all. The funny thing, however, is that Sciurumimus is only relatively distantly related to the Coelurosaurs. Sciurumimus is actually a Megalosauroid, a member of the group which includes Megalosaurus and Spinosaurus. Using Phylogenetic Bracketing, we can now push back the origin of feather-like structures much farther into the history of the Theropods; We can now assume that the most recent common ancestor of the Coeulurosaurs and the Megalosauroids, and all of that ancestor's descendants (a group known technically as the Tetanurae) likely had at least some kind of feather-like structure somewhere on their bodies.

Now, Dilophosaurus is not a member of Tetanurae, so why would that be quilly as well, you may ask? Tianyulong and Psittacosaurus hold the answer. These two animals are Ornithischians, which are as distantly related to birds as a Dinosaur can be. In spite of this, both Psittacosaurus and Tianyulong, two Dinosaurs from different branches of the Ornithischian family tree, have quill-like structures on at least part of their bodies.

This potentially pushes the origin of quilly structures in Dinosaurs even further. It now appears that the most recent common ancestor of Ornithischia and Saurischia (the first Dinosaur) had fuzzy wuill-like structures on at least part of its body, and likely passed that trait down to its descendants.

How can we make this jump? That's where Occam's Razor comes in. You may be thinking it could be possible that quilly structures in all these different Dinosaur lineages are actually not homologous, and evolved totally independently of each other. However, Occam's Razor tells us that the simplest answer to a question is the one most likely to be correct. Maximum Parsimony as it applies to Phylogenetics explains that the Phylogenetic Tree which involves the least evolutionary change is the most likely to be correct. Using these lines of logic, It is now believed, based on the above evidence, that the very first Dinosaur had quill like structures on at least part of its body, and passed that trait on to its descendants.

Also worthy of mention are Pterosaur pycnofibers, because they too are quill like structures. Current thinking suggests that Pterosauria and Dinosauria are close relatives. This could possibly mean that the most recent common ancestor of both the Pterosaurs and Dinosaurs (Avemetarsalia) may have had some sort of quill structure too. Perhaps even more interesting is the presence of feather-building genes in Alligators, because this could potentially mean that the most recent common ancestor of Crurotarsi (Crocodilians and their extinct relatives) and Avemetarsalia also had quills, meaning that fuzziness was the ancestral condition of all Archosauria, which would be a huge deal if it could be proven to conclusively be the case. For starters, it would mean that any Archosaur that is scaly would be secondarily without fuzz, which has interesting implications for the topic of feather evolution.


As you can see, the origin of feathers is a complex topic. The takeaway I suppose is that featherlike structures likely evolved long before the Coelurosaurs did, and were probably present in the earliest Dinosaurs and maybe the earliest Avemetarsalians as well.
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Re: Diversity: Feathered Vs Non-Feathered?

Postby Salmonman » Thu May 09, 2013 2:45 am

Personally I think that completely covering dinosaurs in feathers would make them look too goofy to be taken seriously. Sure you can say that they might have been covered in feathers from head to toe, and SOME fossil evidence might support that, but I feel like a lot of the radical pro-feather people are overcompensating.

There's been so much discovery of feathers among dinosaurs that mainstream depictions ignore, and it seems to me that wanting dinosaurs being big puffballs is just a case of hipsteritis, wanting to stick it to the man and keep as far away from "mainstream" as humanly (saurianly) possible. Then again I am a huge cynic.

As for me I would like to see a compromise. Tyrannosaurus might have a few feathers on its body but it shouldn't look like a bird. And Velociraptor shouldn't either. The pictures in the second post on this thread show 3 depictions of raptors, and I would say that for the sake of the game AND scientific accuracy, the middle one is the best looking. Still more birdlike than any other depiction in a video game thus far, but not so bird like as to lose it's uniqueness, primitive visage, and ferocity.
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