New Insights Into the Brain, Braincase, and Ear Region of Tyrannosaurs (Dinosauria, Theropoda), with Implications for Sensory Organization and Behavior

@article{Witmer2009NewII,
  title={New Insights Into the Brain, Braincase, and Ear Region of Tyrannosaurs (Dinosauria, Theropoda), with Implications for Sensory Organization and Behavior},
  author={Lawrence M. Witmer and Ryan C. Ridgely},
  journal={The Anatomical Record: Advances in Integrative Anatomy and Evolutionary Biology},
  year={2009},
  volume={292}
}
  • L. Witmer, R. Ridgely
  • Published 1 September 2009
  • Biology
  • The Anatomical Record: Advances in Integrative Anatomy and Evolutionary Biology
The braincase region of tyrannosaurs was investigated to provide insights on anatomical attributes relevant to inferences of sensory biology and behavior. CT scanning focused on three specimens of Tyrannosaurus rex, a juvenile Gorgosaurus, and the controversial Cleveland skull (CMNH 7541). Analysis shows that the cerebral hemispheres were enlarged, but conflicting information on the optic lobes suggests that brain conformation was not fully avian. Previous estimates of olfactory bulb size for T… 
New information on the braincase and inner ear of Euparkeria capensis Broom: implications for diapsid and archosaur evolution
TLDR
The braincase of Euparkeria is re-examined using micro-computed tomography scanning and the presence of a laterosphenoid is confirmed, which largely conforms to the crocodilian condition, but shows some features which make it more similar to the avemetatarsalian laterospenoid.
The Braincase of the Theropod Dinosaur Murusraptor: Osteology, Neuroanatomy and Comments on the Paleobiological Implications of Certain Endocranial Features
Abstract. A detailed description of the neuroanatomy of Murusraptor barrosaensis—a mid-sized non-maniraptoran theropod from the Late Cretaceous of north Patagonia—is based on the exceptionally
The internal cranial anatomy of Champsosaurus (Choristodera: Champsosauridae): Implications for neurosensory function
TLDR
Comparisons with lepidosaurs and archosauromorphs demonstrates that the semicircular canals of Champsosaurus are most similar to those of aquatic reptiles, suggesting that Champsaurus was well adapted for sensing movement in an aquatic environment and represents the first morphometric analysis of semicircul canals across Diapsida.
The Braincase of the North American Therizinosaurian Nothronychus mckinleyi (Dinosauria, Theropoda)
TLDR
The results presented here support the model that therizinosaurs possessed weak bite forces as compared to obligatory carnivorous theropods.
Braincase, Neuroanatomy, and Neck Posture of Amargasaurus cazaui (Sauropoda, Dicraeosauridae) and Its Implications for Understanding Head Posture in Sauropods
ABSTRACT The braincase of Amargasaurus cazaui from the Lower Cretaceous of Argentina represents the only dicraeosaurid sauropod neurocranial material known from South America. It has been computer
Endocranial Anatomy of Lambeosaurine Hadrosaurids (Dinosauria: Ornithischia): A Sensorineural Perspective on Cranial Crest Function
TLDR
The large brains of lambeosaurines are consistent with the range of social behaviors inferred when the crest is interpreted as an intraspecific signaling structure.
New Information on the Braincase and Endocranial Morphology of the Late Triassic Neotheropod Zupaysaurus rougieri Using Computed Tomography Data
TLDR
The virtual reconstruction of the braincase of Zupaysaurus shows anteroventrally oriented, finger-like basipterygoid processes, an elongate and horizontally projected cultriform process, and well-developed preotic pendant, basisphenoid recess, and subsellar recess.
Neuroanatomy of Titanosaurid Dinosaurs From the Upper Cretaceous of Patagonia, With Comments on Endocranial Variability Within Sauropoda
TLDR
The variation observed in the sauropod endocranium indicates an evolutionary tendency in titanosaurs toward the anteroposterior shortening of the midbrain, and the reduction in size of the semicircular canals of the inner ear, in particular the anterior semicircul canal.
Neurosensory and Sinus Evolution as Tyrannosauroid Dinosaurs Developed Giant Size: Insight from the Endocranial Anatomy of Bistahieversor sealeyi
TLDR
Bistahieversor had a nearly identical brain and sinus system as tyrannosaurids like Tyrannosaurus, including a large brain, large olfactory bulbs, reduced cerebral hemispheres, and optic lobes, and voluminous sinuses.
The Braincase Anatomy of the Late Cretaceous Dinosaur Alioramus (Theropoda: Tyrannosauroidea)
ABSTRACT The late Cretaceous tyrannosaurid Alioramus altai is known from a single specimen whose articulated braincase exhibits a nearly unique combination of preservational quality, subadult stage
...
...

References

SHOWING 1-10 OF 170 REFERENCES
Structure of the brain cavity and inner ear of the centrosaurine ceratopsid dinosaur Pachyrhinosaurus based on CT scanning and 3 D visualization
TLDR
The structure of the brain of P. lakustai, as inferred from the endocast, was relatively primitive and much more like extant nonavian diapsid endocasts than like endocasting of archosaur groups with derived brains, such as pterosaurs, hadrosaurs, or coelurosaurs (including extant birds).
Neuroanatomy of flying reptiles and implications for flight, posture and behaviour
TLDR
The brain and vestibular apparatus in two pterosaurs are compared based on high-resolution computed tomographic (CT) scans from which they were constructed digital endocasts to shed light on adaptation to an aerial lifestyle.
The Cleveland Tyrannosaur Skull (Nanotyrannus or Tyrannosaurus): New Findings Based on CT Scanning, with Special Reference to the Braincase
TLDR
Although the new findings strongly confirm the long-held view that CMNH 7541 pertains to a tyrannosaurid, the mosaic of characters it presents makes finer taxonomic assignment difficult and the key question that awaits resolution is whether the differences observed can be attributed to juvenility.
The avian nature of the brain and inner ear of Archaeopteryx
TLDR
It is concluded that Archaeopteryx had acquired the derived neurological and structural adaptations necessary for flight and had also developed enhanced somatosensory integration with these special senses demanded by a lifestyle involving flying ability.
Evidence on relation of brain to endocranial cavity in oviraptorid dinosaurs
TLDR
A fragment of a skull roof of an oviraptorid dinosaur, Ingenia yanshini, shows perfectly preserved, numerous vascular imprints that cover the internal surfaces of frontals and parietals in the region roofing the cerebral hemispheres and cerebellum.
Homology of the “Ethmoid Complex” of Tyrannosaurids and its Implications for the Reconstruction of the Olfactory Apparatus of Non-Avian Theropods
TLDR
The components of the “ethmoid complex” are shown to have cartilaginous or osteological homologues among extant archosaurs: the trough is homologous to the anterior portion of the planum supraseptale of crocodylians and embryonic birds, whereas the median septum and overlying dorsal plate are homologously to the avian mesethmoids.
Avian-like attributes of a virtual brain model of the oviraptorid theropod Conchoraptor gracilis
TLDR
The data presented in this study do not allow an unambiguous assessment whether the avian-like endoneurocranial characteristics of the flightless Conchoraptor evolved convergently to those of avian theropods, or indicate a derivation of oviraptorosaurs from volant ancestors.
Braincase structure of the Middle Jurassic theropod dinosaur Piatnitzkysaurus
TLDR
The braincase of the Middle Jurassic basal tetanuran theropod Piatnitzkysaurus floresi is described in detail, and the high number of accessory pneumatic recesses indicates that the presence of an anterior and dorsal tympanic recess, and possibly also of subcondylar and basipterygoid recesses is plesiomorphic for tetanurans.
An unusual braincase (?Stokesosaurus clevelandi) from the Cleveland-Lloyd Dinosaur Quarry, Utah (Morrison Formation; Late Jurassic)
ABSTRACT A basicranium from the Cleveland-Lloyd Dinosaur Quarry is the most advanced of any Jurassic theropod, combining features considered synapomorphies for two different Cretaceous theropod
...
...