blaze
Paleo-artist 
Posts: 766
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Post by blaze on Nov 13, 2013 1:24:59 GMT 5
If that was the case then why they didn't say such thing? they were very adamant on making a dinosaur killer out of Kaprosuchus and their exact description goes for less telescoped eyes instead of binocular visión but whatever, I can sort of see it in dorsal view but the lateral view is not congruent with it, who knows.
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Post by theropod on Nov 13, 2013 1:41:38 GMT 5
An overlap in fields of vision is present in extant crocodilians, to be exact roughly 25% (which is comparable to carnosaurs and pidgeons), and I'm not aware of any vertebrate completely lacking a stereoscopic field.
Good binocular vision is not absolutely necessary for a terrestrial lifestyle, and some taxa didn't evolve an increased overlap, for the sake of balance between field of vision and depth perception.
Censequently hypothetised good binocular vision also is no compelling evidence for a terrestrial lifestyle.
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Post by Godzillasaurus on Nov 13, 2013 2:05:25 GMT 5
But its eyes were still positioned much more foreword when compared to modern crocodilians, whose eyes are positioned more-so on the top of their heads as an adaptation for primarily aquatic life. But even without its eye differences, there are still more features present in modern crocodilians that are not present in kaprosuchus and vice-versa. Here is the skull of kaprosuchus and the skull of the saltwater crocodile for reference:   The skull of the crocodile actually appears to be even more gracile than that of kaprosuchus, as it tapers off into a point and lacks the thick boss at the front of the upper jaw. Fanboys, get your shotguns ready! |
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Fragillimus335
Member
Sauropod fanatic, and dinosaur specialist
Posts: 573
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Post by Fragillimus335 on Nov 13, 2013 5:40:29 GMT 5
Man, Kapro has one cool looking skull....
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Post by Godzillasaurus on Nov 13, 2013 5:42:12 GMT 5
Man, Kapro has one cool looking skull.... Darn tootin! |
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blaze
Paleo-artist
Posts: 766
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Post by blaze on Nov 13, 2013 6:01:10 GMT 5
I'm still only seeing less telescoped eyes not totally front facing eyes, it actually reminds me of the condition seen in young individuals  Either way, even if it was terrestrial, is that really going to get it out of the 3-4m range? I highly doubt it. Talking about robustness...  (I recognize I went overkill here as this is the largest saltie skull on record) Edit I think the "juvenile condition" I saw is not restricted to juveniles. This the skull of an american alligator, 59cm long in the same measure that that of Kaprosuchus is 51cm long.  |
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Post by Godzillasaurus on Nov 13, 2013 6:09:01 GMT 5
^Its eyes definitely were not 100% "foreword facing". But they still didn't represent the same periscope-like purpose as seen in modern crocodilians. In fact, it's snout was actually slanted downwards more-so than in modern crocodilians, whose skulls are more dorsally compressed.
Actually, being a primarily terrestrial animal would likely grant kaprosuchus a shorter skull proportionate to body length. This would make it larger than 10-11 feet long. A smaller skull proportionally is not yet proven, but is likely.
i am am not denying that modern generalist crocodilians have robust skulls, but size and width does not necessarily merit a robust skull. Remember, kaprosuchus had a very rugose snout that was likely covered with a keratinous shield at the front.
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blaze
Paleo-artist
Posts: 766
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Post by blaze on Nov 13, 2013 6:53:05 GMT 5
Its skull is not much less dorsally compressed than that of the saltie and alligator I've shown. And about the size, but larger by how much? really, it isn't going get it back to 6m I'll repost the images above but with the skull of Kaprosuchus for scale   About the keratinous shield... so like horns? how that makes it robust overall? why is the smallest part of the skull the one immediately after the end of the snout? |
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Post by Godzillasaurus on Nov 13, 2013 8:51:31 GMT 5
I am on an ipad, so quoting is a huge pain. I will try to quote your sub-posts when I get to a computer. I will try to provide replies as best as I can.
Size: we obviously don't know how long this specific specimen was when it was fossilized, because we do not have any other bone fragments to work with; just a skull, which we can be very thankful is complete. And we especially don't know if this individual was fully grown or not, which would have made the animal a lot bigger if it was not. It is highly unlikely that this was the ultimate largest individual of this species. But again, we won't know anything else until we find more material to work with. Let's hope we find something new soon.
Keratinous shield: the keratinous shield of the animal did NOT form horns, I can tell you that now. I think I might need to reprase my post a bit; a rugose texture in an animal's snout probably wouldn't make it more robust per-se, but it would provide reinforcement nonetheless. The keratinous shield would definitely fill this role perfectly, especially if it was at the tip of the premaxilla. The tip of the upper jaw of kaprosuchus was actually more bulbous than in modern crocodilians, and would have probably been the base for the shield. In fact, I am even going as far as to say this part of the animal's snout was probably one of its most well-enforced.
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blaze
Paleo-artist
Posts: 766
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Post by blaze on Nov 13, 2013 12:43:13 GMT 5
I didn't meant horns horns, a keratinous shield is a horny (lol) surface as in horn-like.
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Post by theropod on Nov 13, 2013 18:52:31 GMT 5
Crocodilian skulls can look surprisingly different in terms of robustness depending on the angle. Laterally, they often look quite thin, when viewed dorsally they are immensely thick. Larger and older specimens also seem to have get increasingly robust skulls.
Kaprosuchus skull is a little deeper and narrower, this might be consistent with a more terrestrial lifestyle (Seriously, there's very little difference in the arrangement of the eyes, and the overall robusticity is comparable). But speculating on what influences this likely had on its proportions is quite pointless without at least a reference, it is quite unlikely it would exceed the 3-4m range either way.
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Post by Runic on Nov 13, 2013 19:12:26 GMT 5
Perhaps a more temperate approach should be in order? Since I'm terrified of math I had my old teacher calculate a size for kapro using the chart and then using scaling from an alligator skull in our old science lab (it was a 10 footer btw) and when he finished I asked him would it be possible to exceed 5 m and he laughed and said it'd be lucky to pass 4. And from personal experience I've never encountered or heard of a gator or crocodile over 4m with a short skull.
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Post by Godzillasaurus on Nov 13, 2013 20:12:03 GMT 5
Crocodilian skulls can look surprisingly different in terms of robustness depending on the angle. Laterally, they often look quite thin, when viewed dorsally they are immensely thick. Larger and older specimens also seem to have get increasingly robust skulls. Kaprosuchus skull is a little deeper and narrower, this might be consistent with a more terrestrial lifestyle (Seriously, there's very little difference in the arrangement of the eyes, and the overall robusticity is comparable). But speculating on what influences this likely had on its proportions is quite pointless without at least a reference, it is quite unlikely it would exceed the 3-4m range either way. Deeper, perhaps. But narrower? Only in comparison to really large crocodiles (I am talking HUGE crocodiles, as in 17+ feet), as its snout does not taper into a point and remains its overall width throughout, indicating that it preyed on larger terrestrial animals and had a diet less exclusive to fish. Of course, as you already stated, old male crocs can have insanely thick and wide skulls, but this specimen was still probably not fully grown. Again, we only have a skull, so its body to head proportions are unknown |
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Post by Godzillasaurus on Nov 13, 2013 20:52:14 GMT 5
Perhaps a more temperate approach should be in order? Since I'm terrified of math I had my old teacher calculate a size for kapro using the chart and then using scaling from an alligator skull in our old science lab (it was a 10 footer btw) and when he finished I asked him would it be possible to exceed 5 m and he laughed and said it'd be lucky to pass 4. And from personal experience I've never encountered or heard of a gator or crocodile over 4m with a short skull. The catch is that kaprosuchus was not a crocodile or an alligator; it was a mahajangasuchid, which means that its skull anatomy had many differences from true crocodilians. |
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Post by creature386 on Nov 13, 2013 21:16:23 GMT 5
Is there a mahajangasuchid complete enough for scaling?
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