Dinosaur lips?

[gfxtwin]

Informative thread!

[Bread]

About the lips or the lack of them, Italian paleontologist Andrea Cau is developing a mathematical model which is providing very interesting results: it's a work in progress, so nothing official yet, although it gives an idea of how open the debate is. Keep in mind that Cau was more oriented towards the lips.

http://translate.google.com/translate?u=https%3A//theropoda.blogspot.com/2021/04/possiamo-predire-matematicamente-la.html%3FshowComment%3D1618286810720%23c1124261213608192221&hl=en&langpair=it|en&tbb=1&ie=UTF-8

Interesting read, thank you for this. Definitely is a debate or controversial topic. I do not favor one or the other, but I do however respect the decision a company makes to include or show lack of lips on their models. To me at least, companies, like PNSO, can continue to produce figures with no lips until proved otherwise. Again, I do not favor one or the other until a specimen of a therapod is to show an enormous amount of lips or lack of lips.

I will say lips or no lips need to be done correctly on a figure. I do love the new Wilson figure, but there is an issue with its upper jaw having "loose" teeth.

I may well have missed any discussions on the DTF regarding the question that I'm going to raise, so I'm extremely curious as to the answer to it, namely:

since we know that theropods routinely lost teeth during the killing, rending and consuming process of processing their prey, as large numbers of teeth are continuously found, especially near remnants of dead prey victims, why then is it an absolute necessity to have lips present to hydrate the teeth? Since the individual  teeth don't have the duration of use in a theropod's mouth , compared to mammalian teeth, why the need for preservation of the integrity of individual teeth by lips? I've never seen this question addressed, let alone answered.

Comments, Please!

Continuing a conversation and a discussion of lips from the PNSO 2021 thread.

I do not know the answer to this; however, I will add that the whole crocodiles don't have/need lips due to them spending most of their lives in a body of water is not exactly true. Some crocodilians can spend a large period of time out of water without any harm to their mouth's. I've seen this argument for against lips for therapods, but never received anything else regarding this to be a good argument, plus if it exactly supports the argument for no lips.

I'd also like to see if anyone could answer or reply to S @SidB's information posted in the quote above. Thank you

[SidB]

Thank you, @Bread > I have just gone though this most interesting thread with some care , but I don't see any discussion of what I'd consider to be a significant question ... If theropods shed their teeth quite quickly or at least relatively so, would not that eliminate  or at least reduce the the need for lips. Of course, the frequency of shedding, driven, I'm assuming, by the stresses on the roots of the current teeth being pressed by newly emerging ones beneath would be a big question. Just how long, typically, does the current dentition remain in the jaw? Naturally, they would not be forced out or lost by biting stresses all at once.

[HD-man]

I'd also like to see if anyone could answer or reply to S @SidB's information posted in the quote above. Thank you

Thank you, @Bread > I have just gone though this most interesting thread with some care , but I don't see any discussion of what I'd consider to be a significant question ... If theropods shed their teeth quite quickly or at least relatively so, would not that eliminate  or at least reduce the the need for lips. Of course, the frequency of shedding, driven, I'm assuming, by the stresses on the roots of the current teeth being pressed by newly emerging ones beneath would be a big question. Just how long, typically, does the current dentition remain in the jaw? Naturally, they would not be forced out or lost by biting stresses all at once.

Hope this helps: https://thesauropodomorphlair.wordpress.com/2020/09/09/lipped-dinosaurs-and-the-replaceable-teeth-argument/

[SidB]

I'd also like to see if anyone could answer or reply to S @SidB's information posted in the quote above. Thank you

Thank you, @Bread > I have just gone though this most interesting thread with some care , but I don't see any discussion of what I'd consider to be a significant question ... If theropods shed their teeth quite quickly or at least relatively so, would not that eliminate  or at least reduce the the need for lips. Of course, the frequency of shedding, driven, I'm assuming, by the stresses on the roots of the current teeth being pressed by newly emerging ones beneath would be a big question. Just how long, typically, does the current dentition remain in the jaw? Naturally, they would not be forced out or lost by biting stresses all at once.

Hope this helps: https://thesauropodomorphlair.wordpress.com/2020/09/09/lipped-dinosaurs-and-the-replaceable-teeth-argument/

Thank you, yes, that was quite helpful, I appreciate your assistance as PEET has been more than a bit of an assumption on my part.

[GojiraGuy1954]

But at least they are more close to crocodiles that Monitor lizards, an example used to drawn lips on theropods.

Crocodiles are the exception, not the rule. Almost all living tetrapods have lips.

[Bowhead Whale]

But at least they are more close to crocodiles that Monitor lizards, an example used to drawn lips on theropods.

Crocodiles are the exception, not the rule. Almost all living tetrapods have lips.

Well, maybe they are an exception, no question about that. Yet I still wonder if there were once other predators without lips in the past...

[stargatedalek]

But at least they are more close to crocodiles that Monitor lizards, an example used to drawn lips on theropods.

Crocodiles are the exception, not the rule. Almost all living tetrapods have lips.

Well, maybe they are an exception, no question about that. Yet I still wonder if there were once other predators without lips in the past...

Other aquatic predators sure, but not terrestrial ones.

[Funk]

Crocodiles are the exception, not the rule. Almost all living tetrapods have lips.

One thing that is often overlooked is that the presence of lips does not necessarily mean the teeth weren't exposed. Tasmanian devils often have exposed canines, for example.

[stargatedalek]

Tasmanian devils are a great example because their canine teeth are built for being exposed. They are round and smooth, with no serrations.

[GojiraGuy1954]

Tasmanian devils are a great example because their canine teeth are built for being exposed. They are round and smooth, with no serrations.

Agree 100%. Also why I think Smilodon's lips didnt cover the sabers

[Funk]

Agree 100%. Also why I think Smilodon's lips didnt cover the sabers

Smilodon canines have serrations, though.

Some guy claimed no teeth were exposed in terrestrial animals because they needed hydration or something, without even bother to demonstrate how this worked. It almost became palaeoart dogma, though it was never even published beyond an abstract, leading to ridiculous, boxer-like restorations of Smilodon. Hell, there are even housecats with exposed canines that live just fine.

[GojiraGuy1954]

Agree 100%. Also why I think Smilodon's lips didnt cover the sabers

Smilodon canines have serrations, though.

Some guy claimed no teeth were exposed in terrestrial animals because they needed hydration or something, without even bother to demonstrate how this worked. It almost became palaeoart dogma, though it was never even published beyond an abstract, leading to ridiculous, boxer-like restorations of Smilodon. Hell, there are even housecats with exposed canines that live just fine.

Smilodontini sabers have very fine/no serrations

[Funk]

The point is, they did have serrations, and Homotherium had even coarser serrations, but it is of course probable its canines could have been covered, being much shorter.

Anyhow, that serrations should somehow be a determinant factor to whether teeth were exposed or not is an untestable hypothesis at this point.