Dinosaur "Lips" and the Evidence for Them - T. rex as an Example 

I'm sure dinosaurs were much cuter and less scary looking than we currently think.. like the hippo skull meme.. 😂

@@einienj3281 So in that case, could dinosaurs "kiss" like some bird species do for courtship? With the male passing food to the female.

Prior to the 1980s-1990s, dinosaurs were pretty much always depicted like large lizards, with shrink-wrapped bodies and saggy skin, and lizard-like lips. Jurassic Park really was the first serious media I remember seeing that had the toothy look, and along with the rest of the Dinosaur Renaissance features it depicted, toothy T-rex became more popular after that. Having grown up with lipped dinosaurs, I always thought the overbite look was weird.

@@kylecollier7569 there’s no reason to not think that some dinosaurs may have had a very similar behavior, not that it really has anything to do with them having lips because as you said birds do that and they certainly don’t have lips.

​@@patreekotime4578Except velociraptor and dilophosaurus did have lips in Jurassic Park.

Hey! I'm glad you're enjoying the videos. :) Would be nice to play again!

Yup. All the dinos when I was a kid had lizard lips. The overbite look popularized especially in Jurassic Park always looked weird to me. And Charles Knight's murals in the Field Museum are really treasures! I was so happy to see modern mounts next to them to show how reconstructions have changed!

You can't really compare animals now to animals that lived 66 million years ago. There is always the possibility that lips evolved after the extinction of the dinosaurs. And not to mention that there are animals right now that do not have lips, like crocs. And just to be clear I am neither for or against, if there is a discovery that proves dinos had lips, then they had them. Until then all we can do is speculate.

And for animals that don't have some of their teeth covered (Tusked animals) there are likely ways to tell and adaptations separately to help maintain survival that we can detect. Im one of the people who also believes sabertooth tiger teeth are largely covered up save maybe for the tips

@@patreekotime4578 Is it just me, or is current palaeo-art starting to look similar to Knight's? Obviously his art is outdated with the dragging tails and weirdly lizard-like leg musculature, but I've seen a lot of palaeo-art use lizards as inspirations for dinosaur integument, in addition to birds.

@@Bagelgeuse I feel like the thing he did that was unique at the time was dynamic exciting scenes with dramatic lighting... and that kind of emotional context has definitely gotten more popular over the years. He really tried to bring them to life.

That's really appreciated. I'm glad you get something out of them. :) Getting content out for people to learn more is very fulfilling!

My mom is a paleontologist, I know about the Mesozoic and the Pleistocene since I was 4.

@@titaniumaura Oh cool!

Also crocodiles have much thicker enamel than animals that have lips so that it takes longer for the teeth to wear out since they lack lips

Terrestrial crocodiles were a thing though. And there’s no evidence that they had lips. ​Also, lips are difficult to reconcile with the jaw anatomy of some theropods, especially T. rex. Modern reptiles with lips don’t have upper teeth that overlap 3-5 inches below the top of their lower jawbone due to the narrowness of the lower jaw (and we know where their bite stopped due to the bony “doorstop” in theropod jaws), nor teeth that could be up to 2 inches thick. (The closest we have to that jaw structure is crocs, which don’t have lips). Lizards have teeth that somewhat interlock or meet, but do not overlap, and therefore their lips can easily cover their teeth. But lips on theropods would require a very wide and deep “pocket” to cover those upper teeth. So on a T. rex, you’d be looking at a pocket inside the lips at least 5-6” high and 2” deep. That lip would need some sort of support, so it would probably require the entire lower jaw to have 2.5-3.5” of skin and connective tissue over the bone, from the bottom jawline to the top of the gums, and then 1-1.5” thick until the top of the lip. That’s a lot of mass just to support a lip. Oh, and some T. rex specimens have a significant overbite, which would require a comically large non-bony lower jaw extension to support it. And we don’t see any evidence of these structures on T. rex or other theropod skulls. We do see rows of holes in the bone song the gumline which could be for lips, but many theropod skulls (like modern crocs) have those holes all over their skulls. They might have just had very tactile faces. The best explanation I’ve heard as to why we should ignore the similarities between lipless croc skulls and T. rex skulls is that crocs live in the water and don’t need lips to keep their mouths wet. But there have been many terrestrial crocs, and unless there’s evidence that they had lips (of which I am unaware), then they obviously figured out another solution that could have also been used by theropods.

Yeah some people's arguments have boiled down to: the lips would get bruised from the impact of the bite, the teeth could be replaced, the teeth were to big and some idiot said that since their intelligence is like of a crocodile or alligator they didn't have them.

@@34r343 Let them. People are at different levels of knowledge. The "teeth were too big" statements can now be countered with the study of modern monitor lizards. Some have even bigger teeth in relation to their skull than Rex and they don't even overlap when the mouth is closed.

I'm patiently waiting for proof positive one way or another if theropods did or did not have lips. The animals have been extinct for tens of millions of years. Good luck with that.

I wonder though about Spinosaurs and the fan-like teeth at the front... They were also conical and round, and you would expect lipped teeth to be a bit "flattened" for space...

Fish and mammals must have metal lips if they don't rip off lmao.

It's really fun to go over! And same on my end.

Spinosaurus also had a mouth that could close without the teeth damaging it's jaws, and, for catching slippery teeth, the imobile teeth that dinosaurs had would be detrimental to do such!

Because it doesn't align with their biased views. I love jurassic park especially the original trilogy and I'm not meaning anything bad when I say this but they grew up with dated media like jurassic park For some people it's very hard to have something that they have known for a long time challenged.

@@34r343 ah, pretty much what I thought.

@@34r343 And for many of us who remember dino art before Jurassic Park, its much easier because we saw lipped T-rex all the time.

_"Because it looks dumb!"_ There is some overlap with the people who don't like feathers.

@@tjarkschweizer yeah I see that as well some people can't think that there is a possibility of some feathers on tyrannosaurus. Even when they are and almost un noticeable like prehistoric planets rex.

I agree with you there. A lot of the arguments against it don't hold up to well.

@@HenrythePaleoGuy​To me, it is difficult to reconcile lips with the jaw anatomy of some theropods, especially T. rex. Modern reptiles with lips don’t have upper teeth that overlap 3-5 inches below the top of their lower jawbone due to the narrowness of the lower jaw (and we know where their bite stopped due to the bony “doorstop” in theropod jaws), nor teeth that could be up to 2 inches thick. (The closest we have to that jaw structure is crocs, which don’t have lips). Lizards have teeth that somewhat interlock or meet, but do not overlap, and therefore their lips can easily cover their teeth. But lips on theropods would require a very wide and deep “pocket” to cover those upper teeth. So on a T. rex, you’d be looking at a pocket inside the lips at least 5-6” high and 2” deep. That lip would need some sort of support, so it would probably require the entire lower jaw to have 2.5-3.5” of skin and connective tissue over the bone, from the bottom jawline to the bottom of the “pocket,” and 1-1.5” thick to the top of the lip. That’s a lot of mass just to support a lip that may not have been strictly necessary. Oh, and some T. rex specimens have a significant overbite, which would require a comically large non-bony lower jaw extension to support it. And we don’t see any evidence of these structures on T. rex or other theropod skulls. We do see rows of holes in the bone song the gumline which could be for lips, but many theropod skulls (like modern crocs) have those holes all over their skulls. They might have just had very tactile faces. The best explanation I’ve heard as to why we should ignore the similarities between lipless croc skulls and T. rex skulls is that crocs live in the water and don’t need lips to keep their mouths wet. But there have been many terrestrial crocs, and unless there’s evidence that they had lips (of which I am unaware), then they obviously figured out another solution that could have also been used by theropods. So while I’m not opposed to the concept of theropods having lips, I would need to have the above facts reconciled with the lip theory before I sign on to it. And to date, I haven’t heard any such explanation. But maybe T. rex just had big floppy dog jowl lips on the top jaw! How hilarious would that be?

True.

Creepy

I'm thinking spinosaurus and other spinosaurs had that. Especially when you look at the tip of the maxilla it's much more similar to the rugosity of crocodiles. So mabey most of the mouth was covered except the end. Similar to river dolphins.

"I don't think that dinosaurs had lips like reptiles" - _other_ reptiles, they _are_ reptiles

A pretty rushed and patchy claim!

What do you mean with "belong in their own class"? The clade Dinosauria already exists. What more do you want?

Sure!

What? Is it that you need help with saying "First...!" All the time?

Sorry, but we WON'T be taking it! 🤣

Their lips aren't like ours. Whistling required fine control over the movement of the lips, something reptilians have not been demonstrated to have.

Oh no when I was younger I had a teacher do this and I learned to do it on purpose to show how annoying it is. Nowadays I use it to call my old cat indoor when it's night time to avoid predators.

With all that said I didn't notice it or particularly feel annoyed by it.

Still some holdouts, but it's been increasingly diminished.

@@HenrythePaleoGuy honestly you can't tell some people otherwise. Some are so biased that they can't even consider the possibility of it and keep sighting that 2017 daspletosaurus paper despite how many people say that theropod skulls are almost nothing like that of a crocodilian. And after awhile alot of their arguments are pulled out of thin air and don't make any sense.

Perhaps because the animals have been extinct for tens of millions of years, and there is no way to definitively prove one way or the other whether or not theropods had lips. It's all merely conjecture. It's a silly debate that's been going on for decades, with both sides being absolutely convinced that they are correct.

:)

Sorry to hear that. I always try to find a balance.

I think the speed is okay but you can also change the video speed directly on youtube`s toolbar if it helps :)

@@HenrythePaleoGuy thanks

You got anything that says otherwise?

Source?

​@@Rajang6he's just an angry jp simp who can't move on with science