Dinosaur lips?

[Neosodon]

I don't get why people are bothered by comparing the jaws of crocodiles and alligators to the jaws of dinosaurs. Just because crocodiles aren't dinosaurs doesn't mean they can't have similarities. Kind of like Whale Sharks and Whales have similar mouths even though they have less relationship than crocadiles have to dinosaurs.

[Faelrin]

I came here to figure out what this was about after reading the new Saurian update. Reading the paper for now (the abstract details alone are pretty interesting). The fossil looks impressive as well.

Edit: If anyone hasn't yet, I really recommend reading the Soft Tissues section under Results and the Soft tissue interpretations section under Discussion of that paper. It goes over the whole crocodylian and tyrannosaur connections. I think it sounds plausible from my limited understanding of what I just read.

[stargatedalek]

I don't get why people are bothered by comparing the jaws of crocodiles and alligators to the jaws of dinosaurs. Just because crocodiles aren't dinosaurs doesn't mean they can't have similarities. Kind of like Whale Sharks and Whales have similar mouths even though they have less relationship than crocadiles have to dinosaurs.

Whales and sharks both deal with the effects of living underwater, and many of them eat the same foods and compete for similar niches.

Crocodiles and alligators are aquatic ambush predators, theropods are almost all* terrestrial predators and I don't think there has ever been any evidence of dedicated ambush hunting in theropods.
*The few aquatic theropods we have are definitely not ambush predators, so still not comparable.

Even among aquatic animals crocodilians are the minority in having exposed teeth.

Birds have lips (we don't often see them, but they do), so any argument against lips on dinosaurs on the basis of genetics is flawed.

[The Atroxious]

I personally find this very interesting. I for one am not a Jack Horner fan at all, but as people have pointed out this only involves him in a minor way. Yes, the reconstruction in this article is terrible, but we can't dismiss the evidence because of that, either. I'm not an expert on this, so I'll leave it to the more experienced people on this forum to let me know whether it's reasonable to infer superficial soft tissue structures from bone texture.
Assuming this is solid evidence, however, I'd still say that it's bad to generalise. At most, this discovery proves that Tyrannosauridae did not have lips. You can't apply it to all Theropods and certainly not to all dinosaurs, as they are a large and very diverse clade.
Arguments aside, the speculation about horny areas on the face is interesting. We know that facial biting occurred in Tyrannosaurids - if this was a regular form of combat then perhaps horny 'armour' and/or thickened facial scales evolved as a response?

I'll finish with a quick PSA: PLEASE, people, can we not have drama over a discovery. Reasonable criticism and well-founded arguments in favour/against is fine, and in fact I'd encourage it. Getting fanatical about it is not, and I've seen far too much of it on the forum lately. Please, DTF, stay special and don't descend to the level of all my other internet hangouts!

I agree, though I still doubt whether any theropods had lips. This article is something of a vindication of what I've been saying for a long time, but it's such an early observation that later studies could go either way. The way I see it is that crocodilians are close relatives to dinosaurs, so it seems far more feasible to infer that the mouths of dinosaurs were more likely to resemble the mouths of their closest toothed relatives than any number of other, much more distantly related animals. This article seems to be suggesting something very similar, and it's interesting to learn that there may be more information about dinosaur faces in the not-too-distant future.

The accompanying reconstruction shows a lack of finesse or awareness of the subject. And no, the reconstruction is not the be-all-end-all of a claim, but this clearly isn't bad because it was rushed, but rather because of a lack of understanding of the animals anatomy. Big difference between a rushed sketch being bad and a commissioned reconstruction being inaccurate.

Bruh, have you ever seen how GSP draws wings? They're horrendous. If I were to mention all the paleoartists that don't seem to understand basic wing construction, we'd be here all day. There are loads of fantasy artists who can draw feathered wings better than most paleoartists for crying out loud. I've also seen several respectable articles on maniraptors that include pictures of these badly constructed wings, all commissioned reconstructions. It happens. The publishers of the articles don't reject pictures because of wonky anatomy, and moreover you have to understand that the picture included in the article is often done independently of the actual research. You can't accurately judge the merit of the research by the image that accompanies it.

[Neosodon]

I don't get why people are bothered by comparing the jaws of crocodiles and alligators to the jaws of dinosaurs. Just because crocodiles aren't dinosaurs doesn't mean they can't have similarities. Kind of like Whale Sharks and Whales have similar mouths even though they have less relationship than crocadiles have to dinosaurs.

Whales and sharks both deal with the effects of living underwater, and many of them eat the same foods and compete for similar niches.

Crocodiles and alligators are aquatic ambush predators, theropods are almost all* terrestrial predators and I don't think there has ever been any evidence of dedicated ambush hunting in theropods.
*The few aquatic theropods we have are definitely not ambush predators, so still not comparable.

Even among aquatic animals crocodilians are the minority in having exposed teeth.

Birds have lips (we don't often see them, but they do), so any argument against lips on dinosaurs on the basis of genetics is flawed.

There are no animals left today that have jaws more similar to that of a T Rex than crocodiles. Of course they are not identical but they defiantly have similarities. And were did you here birds have lips?


Suchomimus skull in comparison to crocodile skull. The shape of the jaw line is almost identical. There is no better live animal to study and compare the jaws of large carnivorus therapods with than a crocadile.

Scientists can compare their finds to any animal they want too. Just because you don't like the choice of animal they use as a comparison doesn't mean that their discovery is fake.

[stargatedalek]

Anatomy trumps genetics, and behavior trumps anatomy.

If we want to use genetics for every inference we should be reconstructing all dinosaurs with either full coats of feathers and bills or with armored crocodilian scutes. Similarly if we use solely anatomy for every depiction all dinosaurs should be flat. A certain degree of inference is required in reconstruction, and this means cross referencing an animals probable (or in some rare cases proven) behavior with its preserved anatomy to interpret a realistic appearance, then using genetics only to fill in the unknowns after that.

Crocodiles have exposed teeth for very specific reasons. It has nothing to do with the sensory organs on their snouts, crocodiles have exposed teeth because they spend the vast majority of their time with their teeth underwater. A land-based animal can't do this without its teeth being damaged by exposure to the air, we see this in tusked mammals, but not in dinosaurs. And in case someone thought they were going to be smart, most fish don't have exposed teeth because it makes them less hydrodynamic, which is unimportant for an ambush predator like a crocodile.

I'm no longer going to directly reply to anyone who just suggests crocodiles were the best reference for Tyrannosaur anatomy because Suchomimus has a skull superficially and convergently similar to crocodiles in profile shape. I'm low enough on aspirin as-is.

[CrypticPrism]

Oh my god I'm dying, you said birds don't have lips.





You know how there was that whole thing on smilodon having big, floppy jowls? That's because teeth can ROT. Prolonged exposure to air can cause tooth rotting. Crocs are safe from this because they're semi-aquatic, and usually only have short times walking around on land. Dinosaurs were completely terrestrial, which means rotting would happen over and over. And no, there's no "well they just regrew them like sharks" because sharks are RIDICULOUSLY distant from dinosaurs. Birds have lips. Therefore they probably got them from their DIRECT ancestors, theropods. The only reason spinosaurs are depicted as lipless is because it would get in the way of snagging fish. Land theropods would not have this because the lips would swing back when biting prey, therefore keeping them safe from damage. Your defenses completely ignore the flat logic we put up against it.

[CrypticPrism]

Scientists can compare their finds to any animal they want too. Just because you don't like the choice of animal they use as a comparison doesn't mean that their discovery is fake.

By your logic I could compare an Australopithecus to a gecko and no one could criticize my scaly, reptilian dinosauroid.

Sorry for the double post.

[stargatedalek]

I feel like a lot of false archetypes in paleontology are born from a lack of understanding of traits in modern animals.

[Neosodon]

Scientists can compare their finds to any animal they want too. Just because you don't like the choice of animal they use as a comparison doesn't mean that their discovery is fake.

By your logic I could compare an Australopithecus to a gecko and no one could criticize my scaly, reptilian dinosauroid.

Sorry for the double post.

I'm talking about specific traits and behaviors. For example if a paleontolagist said Giraffititan had a long neck to eat from trees like that of a Giraffe. According to your logic that would be totally false because Giraffes are not related to Giraffititan.

The article is saying that Daspletosaurus had texture and scales on it's mouth like that of a crocodile. It didn't say that there was some sort of connection between Daspletosaurus and crocodiles. It was just stating a simple comparison to give the reader a better understanding.

[CrypticPrism]

Your logic is a mess. Also, no. My logic never asserted that. And your logic is messier when reading it over. You're saying my logic is saying ONLY giraffoids could be browsers. Behavior and niche have nothing to do with anatomy. And no. The ENTIRE article was comparing daspletosaurus to crocodiles.

[stargatedalek]

Crocodiles don't even have scales on their mouths, they have hard skin.

There isn't even any evidence to suggest these patterns correlate to a lack of lips in crocodiles, let alone that a similar pattern would mean the same for a completely different animal, eating different prey, in a different environment.

[CrypticPrism]

I wish there was a like button.

[Neosodon]

Your logic is a mess. Also, no. My logic never asserted that. And your logic is messier when reading it over. You're saying my logic is saying ONLY giraffoids could be browsers. Behavior and niche have nothing to do with anatomy. And no. The ENTIRE article was comparing daspletosaurus to crocodiles.

Ok, I'll use a better example. If a article compared the beak a quetzocuatlus to that of a blue heron you wouldn't say it was a false article would you? The article points out that Daspletosaurus may have had a sensory system like that of a crocodile and it is even backed up by fossil evidence. If it was the other way around and said that Daspletosaurus had this and this because crocodiles had it than yeah it would be very faulty but that is not what the article is doing. It sounds like what your are saying is that no two animals can have the same trait. As if Daspletosaurus couldn't have that kind of sensory system because crocodiles had it first so there for they are not going to allow any other species to steal their original traits. Sounds kind of silly but I can't think of any other way to describe it.

But I do agree that I didn't see the evidence for not having lips. I'm not sure how they came up with that idea.

[CrypticPrism]

HAHAHA wait what? You're still going on with erroneousness even though you've been very obviously shot down several times with pure logic. What? "Not allowing animals to steal original traits"? You're being, flatly, ridiculous. Somehow you've gotten the idea I don't believe in convergent evolution because of my disagreement with a single article.

[Neosodon]

Crocodiles don't even have scales on their mouths, they have hard skin.

I hope your referring to inside a crocodiles mouth.

[Faelrin]

Okay I'll be honest here, but I had absolutely no idea there were any birds with lips. This whole time I thought the beak replaced the need for lips. Any other good examples (or just point me in the right direction on what to search for)? The more I find out about birds, the more I realize I know very little on them after all.

Also did anyone see the edit of my post above? Did anyone read those sections yet? For those that did, and really know their stuff, help to clarify what it is getting at? I just don't want to misinterpret it based on my poor understanding.

[Neosodon]

Somehow you've gotten the idea I don't believe in convergent evolution because of my disagreement with a single article.

Yeah, that's it. But you've discredited an entire article without pointing out any specif facts that are wrong. Not counting that it uses crocodiles to describe what the anatomy of a Tyrannosaur mouth looked like or the lip thing because it doesn't really talk about it. Can you actually disprove that it had scales on it's head and a complex sensory system. Because that it what the article is really about.

[CrypticPrism]

Wait, I haven't pointed out anything wrong? What is with this? Making claims that just slide over the truth isn't rational, and it's not what this forum is for. We're supposed to be united by a common liking, not torn apart by it.

[Dyscrasia]

Despite this whole "lip" controversy, I am happy to see that the Two Medicine Tyrannosaur is officially named.

Unfortunately, my paper was also published in the same journal at the same day with this paper...