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Tyrannosaurus rex
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Now, the T.-rex is a very smart dinosaur ! That is the great tendancy nowaday.
Here, you are a few videos illustrating this: At first, the video I posted in an other thread (Dinosaur news): It's explaned the new principe: rather than dividing the brain weight by the body weight (EQ), a scientist Suzana Herculano Houzel prefers to consider the neuron density in the "pallium", the brain region that forms the cortex and the area that predicts the innovativ ability in birds which are the closest relatives of the theropods. By this method, the results are very amazing: T-rex with 3,3 billion neurons for a 343 grams-brain. That is more than in the baboon's brain. In fact the t-rex. are only exceeded by chimps and humans. So here are other few other videos about these performing t-rex's brains: Non exhaustiv list... To tell you the truth, I didn't watch them all... But we can consider that the t-rex's intelligence is the new subject that shakes the internauts community interested by the paleontology. What do I think about that ? Even if we, humans, are very good at going from one extreme to the other, it's a very good news. Because reality is much more fascinating than preconceived ideas (dinosaurs were all stupid animals, humans are the only one intelligent ones and so on). That makes us think about it... 
According to the latest study on soft tissues in Tyrannosaurus fossils, onlinelibrary.wiley.com/doi/10.1111/joa.13388 Keratan sulfate as a marker for medullary bone in fossil vertebrates, the so-called "medullary bone" inside the bones of Tyrannosaurus especially MOR 1125 a.k.a B-rex may be turned out to be unrelated to eggshell formation at all.
"Implications for sex determination in extinct archosaurs Several researchers have reflected on a set of criteria to confidently identify medullary bone and distinguish this reproductive tissue from other bone tissue types in the fossil record (see Chinsamy et al., 2016; O'Connor et al., 2018 and the recent review in Canoville et al., 2020a). However, the confident identification of this tissue in fossil specimens remains problematic. The development of definitive morphological criteria for medullary bone in extinct species is complicated by the structural variation observed within living birds (Canoville et al., 2020a; O'Connor et al., 2018), the possibility that the morphology of medullary bone varied during its early evolution (Canoville et al., 2020a) and may not be consistent with what is observed in extant birds, and the fact that medullary bone shares microstructural characteristics with certain pathological tissues (Beresford, 1981; the present study). Here we demonstrate similar challenges in medullary bone identification that result from chemical overlap with pathological tissues. In the absence of preservation or treatment biases (a particular problem for fossil materials), our results indicate that the absence of keratan sulfate can be used to reject a hypothesis of medullary bone (i.e., all medullary bone contains keratan sulfate) and conversely, that the presence of keratan sulfate is inadequate to rule out the alternative hypothesis of pathological origin for potential medullary bone tissues in fossil vertebrates (i.e., keratan sulfate is present in medullary bone and also in some pathological bone, particularly those containing chondroid bone). Confident identifications of medullary bone in fossil vertebrates currently require multiple morphological, developmental, chemical, and location-based (e.g., skeletal distribution patterns, inverse relationships with pneumaticity) criteria to amass a preponderance of evidence (e.g., Canoville et al., 2020a; Chinsamy et al., 2016; O'Connor et al., 2018). No single criterion can be used to reject a hypothesis of pathological origin for endosteal tissues in fossil vertebrates." 
Thank you so much for this thread on tyrannosaurus rex. Being a massive dinosaur worshiper myself, it's always a pleasure to discover more about this magnificent creature that is the great apex predator! I've read that a dinosaur's brain is no bigger than a walnut, which is rather comical considering the size of these reptiles!
@jurassiclove
" I've read that a dinosaur's brain is no bigger than a walnut " It's an absurdity, a nonsense. It was been told that about stegosaurs, but here, at last it is admitted we spoke about a predator enjoying very acuted senses, particularly smell and vision. Thus the olfactory lobes need to be developped. Then, once again, the idea of "neuronal density" explained by Suzana Herculano Houzel is a very attractive one. Clearly dinosaurs are not mammalien, so it's absurd to only consider the weight of the brain between two classes of animals having anything in common. Crows are the most performing actual birds in term of intelligence and among the most smartest animals which exist. Yet we can guess their brain doesn't exceed a fews grams. Same thing as concerns the octopus. Suzana Herculano Houzel's theory should be admitted till we find a counterexample.
My previous post: I wrote " having anything in common. "
Sorry, I wanted to write "Having nothing in common".
Who here has seen season 2 of Prehistoric Planet on Apple TV? I did and I thought it was great!
Also are we in agreement that Tyrannosaurus Rex was the heaviest land predator of all time and that it could reach weights of 10 tons?
I just come to finish listening this video. An allocution from Stephen Brusatte about T-rex. So what news about them ? The first T-rex have been dated from 170 millions years ago and were rather "pretty modeste". During a very long time the Tyrannosauridae were long-snouted predators ("Pinnochio T-rex called them with humor the narrator), and it was finally at the extreme end of the dinosaurs story that they became clearly dominant ones in North America (T-rex) and in Asia (Tarbosaurus bataar).
Till now, the most complete description about the T.rex I have ever heard, its physical caracteristiques, its epoch and so on.
Interesting account about the third t-rex's skeleton "Cope" discovered in 1999. It would be the heaviest, more than Sue and Scotty other famous t-rex whose a great part of the skeleton was previously discovered.
" The true size of Tyrannosaurus rex is hotly debated. Tyrannosaurus rex is the megatheropod with the largest sample size, which may lead to finding the biggest specimens. The gigantic Tyrannosaurus rex specimen E.D. Cope, “Copium rex,” may be the biggest Tyrannosaurus rex specimen yet described in the literature. This video takes measurements from paleontologists and uses them to calculate how big was the biggest Tyrannosaurus. E.D. Cope was likely bigger than Scotty, Sue, Trix, and almost any other theropod. With new estimates placing it at approximately 1500 kilograms heavier than even the dentary Giganotosaurus specimen. "  (10-29-2023, 12:51 AM)Spalea Wrote: Interesting account about the third t-rex's skeleton "Cope" discovered in 1999. It would be the heaviest, more than Sue and Scotty other famous t-rex whose a great part of the skeleton was previously discovered.
An interesting video about the T.rex. Did it hunt the big sauropods ? The filmmaker makes a good comparaison with the giganatosaurus, weaker but faster than the T.rex, with a lesser powerful bite. The latter could bite and release and bite again its prey, and doing this in pride it's easy to imagine it hunting big sauropods. The T.rex had to maintain its powerful bite in order to cruh the bones but doing this it lost its mobility. So I don't think it hunted actively the healthy sauropods, even, if of course, it could be interested by a wounded one.
" G'day ladies and gentlemen, I'm back with another video starring yet again the king of the tyrant lizards; T.rex. More focally, on the topic of whether or not it hunted sauropods during its existence. We all know that it took on the mighty triceratops and the walking tank of the ankylosaurs. But how about we dive into its largest potential prey item yet! "
A short video recapitulating recent theories and discoveries about t-rex...
" Tyrannosaurus Rex, often referred to as T-rex, belongs to the genus of large theropod dinosaurs, a closely related group within the coelurosaurian theropods. This group can be further classified into two subfamilies: the relatively slender albertosaurines, represented by species like Albertosaurus and Gorgosaurus. and the later larger tyrannosaurines, which include not only the famous Tyrannosaurus rex, but also other genera, such as Daspletosaurus, and the Asian Tarbosaurus. The name 'Tyrannosaurus rex' itself translates to 'Tyrant lizard' from Greek and 'king' from Latin. The origins of these creatures can be traced back to the middle Jurassic period, within the superfamily Tyrannosauroidea. Just like other megatheropods, T-rex had muscular hind limbs adapted to support its huge bulk. But despite having brawny legs, these beasts likely weren't built for speed. T-rex's estimated pace was around 4.6 km/h. with estimated sprinting speeds around 19 km/h. If any faster, and T-rex risked shattering its bones under its own weight. The original ancestors of T-rex equipped with longer three-fingered forelimbs. However, when they continued to evolve into massive sizes, their hands shrank in size and retained only two functional digits. Another remarkable aspect of T-rex is its massive and exceptionally sturdy skull, stretching over 5 feet long. Sporting formidable jaws lined with some 60 serrated teeth, and some even measuring up to 12 inches in length, they rank as the most dangerous carnivore in the dinosaur kingdom. Teamed with powerful jaw muscles generating forces of 35,000 newtons, equivalent to 7800 pounds per square inch. "
Interesting... I will seek how it is possible to study and estimate that sound. It's a kind of pelican but much more deafer and powerful.
Another video about the T.-rex's vocalizations. Nothing new compared with the previous one. It sounds very clearly like hippos, when they open their big mouth !
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