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Post by ningishzida on Dec 16, 2008 2:09:17 GMT
I don't see any evidence for the lips. Here's how I see the train of thought: T-Rex had big teeth. Squamates have big teeth and lips. Therefore, T-rex had big lips. You could apply that way of thinking to prove that any extinct animal had any physical feature, for example: Sabre-tooth cats are large felines. Leopards are large felines with spots. Therefore sabre-tooth cats had spots. Just my 2 cents... But there is a very good reason for the lips. Just like mammals, it is necessary to seal the mouth in order to bring air through the nostrils. The 'no lips' theory is based purely on our cosmetic desire for dinos to 'look cooler', wherqs the lips parallel animals with identical type teeth, and the ability for reptiles to use their remarkabl olfactory capabilities. If you had no lips you could not smell very well.... nor could a dinosaur. |
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Post by therizinosaurus on Dec 16, 2008 2:10:32 GMT
Sorry, I know I'm playing devil's advocate, but there is a good reason for spots- camouflage. Maybe that's why smilodon could have had them.
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Post by stoneage on Dec 16, 2008 4:08:50 GMT
;D Exactly! ;D
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Post by stoneage on Dec 16, 2008 4:16:03 GMT
I don't see any evidence for the lips. Here's how I see the train of thought: T-Rex had big teeth. Squamates have big teeth and lips. Therefore, T-rex had big lips. You could apply that way of thinking to prove that any extinct animal had any physical feature, for example: Sabre-tooth cats are large felines. Leopards are large felines with spots. Therefore sabre-tooth cats had spots. Just my 2 cents... But there is a very good reason for the lips. Just like mammals, it is necessary to seal the mouth in order to bring air through the nostrils. The 'no lips' theory is based purely on our cosmetic desire for dinos to 'look cooler', wherqs the lips parallel animals with identical type teeth, and the ability for reptiles to use their remarkabl olfactory capabilities. If you had no lips you could not smell very well.... nor could a dinosaur. ;D Well Alligators have a well developed sense of smell that they use to find food and potential mates. How do they do it without lips. ;D |
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Post by crazycrowman on Dec 16, 2008 5:19:27 GMT
"But not ALL felines of today have spots..."
Unless a domesticated color morph, yes, all felines are born with spots/markings with the single exception of the Caracal. Some change color and become tan/uniform as they mature, but as kittens, they are all marked.
"If you had no lips you could not smell very well.... nor could a dinosaur."
Crocodilians, Turkey Vultures, and Snapping turtles as examples seem to do just fine sans lips...
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Post by kuni on Dec 16, 2008 16:24:01 GMT
Read some of those articles, and it looks like a) paleoartists and paleontologists have known about this for a while and b) that's why we usually see only the front teeth exposed on a T-rex, for example. Also, I looked at the skull of a T-rex:  And then I looked a the skull of a varanid:  and I gotta say, those tooth proportions aren't the same. Interestingly, an allosaur skull is close:  ...but even then, it's a bit bigger in proportion. |
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Post by sbell on Dec 16, 2008 17:51:08 GMT
Naah...That could be possible for Dromeosaurids and other small-medium sized theropods...But for animals with BIG upper teeth like Tyrannosaurids,Tetanurans and Ceratosaurids having bigass lips,sorry,that's NOT realistic  They probably had lips,but not as prominent as in Varanids and other lizards. So,according to this theory,even Smilodon probably had a pair of big,fleshy lips to hide his "swords" ;D ;D Actually, perhaps not lips, but many sabre-toothed mammals had a flange that sheathed the sabre--at least one side of it. As for spots (and let's be less specific--'markings' is a better term to include stripes, rosettes, and marbling)--it is not just the cats; the entire aeluroid lineage is pretty much patterned in some form (genets, civets, hyenas, cats, most mongooses). So it may be accurate to assume that, at some point in their lives, machairodont cats had markings. |
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Post by crazycrowman on Dec 16, 2008 20:34:21 GMT
Read some of those articles, and it looks like a) paleoartists and paleontologists have known about this for a while and b) that's why we usually see only the front teeth exposed on a T-rex, for example. Also, I looked at the skull of a T-rex - and then I looked a the skull of a varanid - and I gotta say, those tooth proportions aren't the same. Interestingly, an allosaur skull is close...but even then, it's a bit bigger in proportion.  Some monitors have longer teeth then others. The Salvadori's monitor has the longest teeth of any monitor lizard. They are arboreal predators of small mammals, birds and bats, though like all monitors it will take carrion as well. (as a side note, also notice that the monitors jaws do not "sit flush" when closed like the crocodilians, therapods, or even birds jaws do - there is no room in a varanids jaw for "overlap" of teeth on the jaw, similar to the mouths of snakes)  I will add that there is a HUGE deal of difference in the skull of a monitor Vs a therpod. Now, Monitor Vs Platecarpus..Not so different at all. www.michaelcovel.com/images/trex_155.JPGRex, and it blows up large so you can get close views.  Crocodilian - Specifically, American Alligator - I know the pitting in the skull for the "lips" is there in theropods, but on a whim I looked through my crocodilian skulls in the living room and there is much pitting there, even those these animals lack lips. To me, it appears that therpod skulls look somewhere between the 2 in regards to pitting for lips.  |
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Post by kuni on Dec 16, 2008 21:06:51 GMT
Wow, that's an awesome set of varanid skulls!
Interesting that crocs and alligators have that same "pitting" -- it sounds like the "hybrid" hypothesis, where lips cover the smaller teeth, and the larger teeth stay outside the sealed jaws, makes a lot of sense.
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Post by ningishzida on Dec 16, 2008 23:20:44 GMT
"But not ALL felines of today have spots..." Unless a domesticated color morph, yes, all felines are born with spots/markings with the single exception of the Caracal. Some change color and become tan/uniform as they mature, but as kittens, they are all marked. "If you had no lips you could not smell very well.... nor could a dinosaur." Crocodilians, Turkey Vultures, and Snapping turtles as examples seem to do just fine sans lips... Yes, but crocodilians have a solid palette and a windpipe that opens behind the throat valve..... and adaption for amphibious life we do not see in the theropods. (Though it would be interesting to see if Spinosaurus has this adaption.) The point then, is crocodilians don't need lips because their throat valve seals the mouthway, wheras other reptiles and arhosaurs don't have this aquatic feature, and therefore need lips to seal their mouth's shut. |
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Post by [][][]cordylus[][][] on Dec 16, 2008 23:28:14 GMT
"But not ALL felines of today have spots..." Unless a domesticated color morph, yes, all felines are born with spots/markings with the single exception of the Caracal. Some change color and become tan/uniform as they mature, but as kittens, they are all marked. "If you had no lips you could not smell very well.... nor could a dinosaur." Crocodilians, Turkey Vultures, and Snapping turtles as examples seem to do just fine sans lips... Well, they are all "marked" but some don't have "spots". When I say spots, I mean something like "polka dot". ;D |
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Post by [][][]cordylus[][][] on Dec 16, 2008 23:31:52 GMT
"But not ALL felines of today have spots..." Unless a domesticated color morph, yes, all felines are born with spots/markings with the single exception of the Caracal. Some change color and become tan/uniform as they mature, but as kittens, they are all marked. "If you had no lips you could not smell very well.... nor could a dinosaur." Crocodilians, Turkey Vultures, and Snapping turtles as examples seem to do just fine sans lips... Yes, but crocodilians have a solid palette and a windpipe that opens behind the throat valve..... and adaption for amphibious life we do not see in the theropods. (Though it would be interesting to see if Spinosaurus has this adaption.) The point then, is crocodilians don't need lips because their throat valve seals the mouthway, wheras other reptiles and arhosaurs don't have this aquatic feature, and therefore need lips to seal their mouth's shut. How do we know for sure that they didn't have it? Isn't the palette just cartilage/soft tissue? |
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Post by Dinotoyforum on Dec 16, 2008 23:41:29 GMT
Yes, but crocodilians have a solid palette and a windpipe that opens behind the throat valve..... and adaption for amphibious life we do not see in the theropods. (Though it would be interesting to see if Spinosaurus has this adaption.) The point then, is crocodilians don't need lips because their throat valve seals the mouthway, wheras other reptiles and arhosaurs don't have this aquatic feature, and therefore need lips to seal their mouth's shut. How do we know for sure that they didn't have it? Isn't the palette just cartilage/soft tissue? No - it is bony. |
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Post by Tyrannax on Dec 16, 2008 23:42:42 GMT
Its a bony flap, CT. ;D
Like a valve, that opens and closes.
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Post by Dinotoyforum on Dec 16, 2008 23:46:06 GMT
Its a bony flap, CT. ;D Like a valve, that opens and closes. The valve isn't bony, just the palate. |
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Post by Tyrannax on Dec 16, 2008 23:49:59 GMT
You lost me. Whats the difference?  I remember seeing a bony flap inside the neck of a crocodile skeleton a while back. That is the water valve, per say, isn't it? |
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Post by Dinotoyforum on Dec 17, 2008 0:02:28 GMT
You lost me. Whats the difference? I remember seeing a bony flap inside the neck of a crocodile skeleton a while back. That is the water valve, per say, isn't it? The palate specifically refers to the bones forming the roof of the mouth. I don't know of a bony flap - the 'palatal valve' is all 'soft tissue', i.e. not bone, and it is not part of the palate, only associated with it.  |
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Post by Tyrannax on Dec 17, 2008 0:11:29 GMT
Then I was thinking pallet.  |
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Post by Dinotoyforum on Dec 17, 2008 0:14:35 GMT
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Post by Dinotoyforum on Dec 17, 2008 0:21:52 GMT
You lost me. Whats the difference? I remember seeing a bony flap inside the neck of a crocodile skeleton a while back. That is the water valve, per say, isn't it? The palate specifically refers to the bones forming the roof of the mouth. I don't know of a bony flap - the 'palatal valve' is all 'soft tissue', i.e. not bone, and it is not part of the palate, only associated with it. ...but! In human anatomy at least "the palate is divided into two parts, the anterior bony hard palate, and the posterior fleshy soft palate or velum" says wikipedia. Maybe 'soft palate' is the correct terminology in crocs after all? I bow down to Tyrannax ;D |
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