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Old December 22nd, 2017, 05:47 PM   #31

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How would you rate the dinosaur in my avatar?
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Old December 22nd, 2017, 11:50 PM   #32

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If you compare corvids to any other dinosaurs, particularly non avian ones, then they are almost like "ascended" beings in the Stargate sense. But I'm being biased on this...
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Old December 23rd, 2017, 04:05 AM   #33

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On the one hand, there are a lot more factors which make a dinosaur interesting than purely size and sophistication. And secondly I would argue that there were, for example the closely related Tarbosaurus bataar.
I don't think so. T. bataar doesn't appear to have been as big as T. rex nor as powerfully armed. Hurum and Sabath noted the posterior of a T. rex skull is expanded (conferring more space for muscle attachment) whereas that of Tarbosaurus is not. So not only did T. rex have far more powerfully muscled jaws (and more robust teeth) it also may have had stereopsis. Bakker btw said even its ears faced forward.
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Old January 3rd, 2018, 01:54 AM   #34

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The BBC documentary "The Real T.Rex with Chris Packham" delivered the goods I think. I could quibble about it not containing enough information, for instance not showing precisely how tyranosaurs are related to today's birds, and so leaving this rather vague in the viewers mind, but it's a mass market documentary intended as entertainment. The scientific expert is David Hone, the author of a superb monograph on T.rex published in 2016.

For the viewer who has not followed all the developments over the last years, this will bring them up to date, and in fact lead them into a cutting edge area of research. The documentary gave some time to Larry Witmer, who showed his CT scans of a T.rex skull and the cast made of it's brain case. While I think this has been touched on before in other documentaries, I believe this is the first time for a general audience that the brain of T.rex has been unequivocally described as a "bird brain", and mention made of the latest discoveries of the miniaturization within the "bird brain" and the huge number of neurons it contains in proportion to it's size. When dealing with a dead animal we deal in speculation as to it's internal brain structure of course, but to me that it even gets mentioned is a big step forward in the public discussion of potential dinosaur intelligence.

Phil Currie also got a platform to further go into his theory of T.rex as a social animal and a pack hunter. A CGI reconstruction of a juvenile T.rex was shown and described as athletic, fast, and may have had the function, as younger lions, of flushing out prey into the jaws of the slower adults. This is not new, but I thought it a pity that there was no discussion about how fast a juvenile T.rex could run, and compare that to how fast a hadrosaur, such as Edmontosaurus, could run.

The part about how T.rex may have sounded and what body covering it had was of course conjecture, but I thought more realistic than previous attempts, and they did in fact poke fun at some depictions of T.rex as a giant chicken.

Until further evidence about T.rex comes to light, then I guess this will be the definitive mass market documentary about them for a little while to come. It certainly showed T.rex to have been underestimated rather than overestimated, Jurassic Park top running speed apart.

Last edited by Corvidius; January 3rd, 2018 at 02:19 AM.
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Old January 3rd, 2018, 11:47 PM   #35

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Clip of part of Whitmer's contribution. It's only after the end of this clip that he goes into explaining the various structures and talks about "bird brains".
BBC Two - The Real T rex with Chris Packham, Getting inside T. rex's head
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Old January 4th, 2018, 03:30 AM   #36

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I believe this is the first time for a general audience that the brain of T.rex has been unequivocally described as a "bird brain", and mention made of the latest discoveries of the miniaturization within the "bird brain" and the huge number of neurons it contains in proportion to it's size.
Long ago, McLoughlin made essentially this point. Based on avian brains, we shouldn't infer that dinosaurs were dim witted because of the relatively small size of their brains.

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When dealing with a dead animal we deal in speculation as to it's internal brain structure of course, but to me that it even gets mentioned is a big step forward in the public discussion of potential dinosaur intelligence.
For quite some time researchers have been saying that the olfactory and visual lobes were large, the cerebrum less so (though T.rex still could've been smart).

Quote:
Phil Currie also got a platform to further go into his theory of T.rex as a social animal and a pack hunter. A CGI reconstruction of a juvenile T.rex was shown and described as athletic, fast, and may have had the function, as younger lions, of flushing out prey into the jaws of the slower adults. This is not new
Right, Phil wrote a nice chapter, which touched on T.rex hunting technique, in the Hadrosaurs volume.
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Old January 4th, 2018, 06:02 AM   #37

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For quite some time researchers have been saying that the olfactory and visual lobes were large, the cerebrum less so (though T.rex still could've been smart)
This is preaching to the converted, but forgive me if I take the liberty of using this reply as a platform to bang a drum about dinosaur intelligence

I think T.rex has suffered from old and false information still lingering in the popular imagination. Focusing only on coelurosaurs to avoid getting too complicated, back in the days they saw them as just another reptile and with it's brain only occupying about half of it's brain case. Of course we have known for a little while that it's brain occupies it's entire brain case just like a mammal. This at a stroke increases T.rex and all it's relatives EQ by 100%, and so it's potential intelligence by that amount. Then back in the days it wasn't realized that the coelurosaur brain was proportionally twice the size of the tetanuran brain. So we can give T.rex another 100% increase over what it's potential for intelligence was thought to be. This makes T.rex potentially four times as intelligent as previously thought.

We cannot and never will know what it's internal brain structure was like, but I think we should make some presumption that the increased neuronal count in modern bird brains began with the advent of the coelurosaur brain. Even the "dimmest" and most basal modern birds have proportionally six times more neurons than a mammal. I think this neuron increase began at the dawn of coelurosauria, and that even non avian coelurosaurs by the end of the Cretaceous probably benefited from extra neurons. T.rex, or for that matter any tyranosaur or non avian maniraptor, if it had just a two fold increase in neurons, would be more intelligent than the EQ scale we use at the moment. While the absolute number of neurons an animal has is a major factor in intelligence, the actual size of the brain when it comes to avian dinosaurs and all coelurosaurs is no longer the limiting factor in intelligence that it once was. Troodon has an EQ of about 0.64, but this pays no attention to it's neuronal density, which is still assumed to be at the level of a modern reptile, ie dismally low. I see no reason why, with increased neuronal density, that Troodon's intelligence may, in EQ terms, be as high as 1.0, and that is normal for a modern mammal like a cat. T.rex could have been as intelligent, not as a troodon, but maybe an equivalent of about 0.5 EQ, about the same as a mammal of the late cretaceous, and slightly more than twice as intelligent as a hadrosaur, which were the smartest ornithischian dinosaurs.
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Old January 5th, 2018, 01:53 AM   #38

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and slightly more than twice as intelligent as a hadrosaur, which were the smartest ornithischian dinosaurs.
Source, or evidence? Of course hadrosaurs had very keen senses, hence large olfactory and visual lobes, but cerebrums?
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Old January 5th, 2018, 02:55 AM   #39

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Ornithopoda had a brain EQ on the reptilian scale ranging from about 0.8 to 1.6
They are measured on the reptilian scale because, unlike coelurosaurs, their brain does not fill their brain case. The actual percentage of brain within their brain case varies from the 50% which is the norm for reptiles, to a higher percentage, maybe 75% maximum, though I'm not totally sure on the exact highest. Iguanodon comes in at about 1.4, with the much later and more advanced hadrosaurs at 1.6. On the reptile scale, T.rex comes in at 2, but the reptile scale is presuming that the brain does not fill the brain case, and as it does for T.rex, then they should be rated at higher than two on the reptile scale. In fact they should not, IMO, be measured on the reptile scale at all, but the mammal scale just as birds are. From the raw facts of the reptilian EQ scale of a hadrosaur having a maximum brain EQ of 1.6 and T.rex 2.0, then T.rex is at least just about half as intelligent again as a hadrosaur. However, as the coelurosaur brain fills the brain case and is more advanced than the brain of a hadrosaur, I think it reasonable to give T.rex the extra points and make him twice as potentially intelligent than a hadrosaur.

Remarkable preservation of brain tissues in an Early Cretaceous iguanodontian dinosaur | Geological Society, London, Special Publications

What I like about this information is that it shows some long extinct and supposedly very dim witted dinosaurs to be more intelligent than living crocodilians.
Click the image to open in full size.

Last edited by Corvidius; January 5th, 2018 at 03:06 AM.
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Old January 5th, 2018, 05:31 AM   #40

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I'll quote from Fastovsky & Weishampel, "Dinosaurs, a concise natural history", Cambridge 2016.

From page 309
Quote:
Thoughts of an ornithopod
By dinosaur standards, ornithopods were smart - as smart or smarter than might be expected of living archosaurs if they were scaled up to dinosaur size. For example, Leaellynasasaura, a basal ornithopod from Victoria, Australia, was apparently quite brainy and had acute vision, as suggested by prominent optic lobes in the brain. In general, euornithopod smarts may be related to greater reliance on sight, smell, and hearing for protection that, in the absence of other means, may have been their only defence. Morever, brain size in these dinosaurs may also have been an integral part of a complex behavioral repertoire.
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