Neuroanatomy of flying reptiles and implications for flight, posture and behaviour

  title={Neuroanatomy of flying reptiles and implications for flight, posture and behaviour},
  author={Lawrence M. Witmer and Sankar Chatterjee and Jonathan Franzosa and Timothy Rowe},
Comparison of birds and pterosaurs, the two archosaurian flyers, sheds light on adaptation to an aerial lifestyle. The neurological basis of control holds particular interest in that flight demands on sensory integration, equilibrium, and muscular coordination are acute. Here we compare the brain and vestibular apparatus in two pterosaurs based on high-resolution computed tomographic (CT) scans from which we constructed digital endocasts. Although general neural organization resembles birds… 
The Evolution of Avian Intelligence and Sensory Capabilities: The Fossil Evidence
Current refinements in quantification of brain structures in extant birds are improving the reliability of the information derived from the external surface of endocasts, which should result in a better understanding of the palaeoneurology of extinct birds and other dinosaurs.
Comparative analysis of vestibular ecomorphology in birds
The hypothesis that the lengths, streamlines and angles between the semicircular canals are related to body size, wing kinematics and flying style in birds is tested and a link between visual acuity and proportional size of the labyrinth among birds is tentatively indicated.
Shake rattle and roll: the bony labyrinth and aerial descent in squamates.
This work uses conventional and synchrotron μCT scans to quantify the morphology of the vestibular system in squamates able to perform controlled aerial descent compared to species characterized by a terrestrial or climbing life style and shows clear differences among animals with different life-styles.
Respiratory Evolution Facilitated the Origin of Pterosaur Flight and Aerial Gigantism
Various lines of skeletal evidence indicate that pterosaurs had a highly effective flow-through respiratory system, capable of sustaining powered flight, predating the appearance of an analogous breathing system in birds by approximately seventy million years.
Avian Cerebellar Floccular Fossa Size Is Not a Proxy for Flying Ability in Birds
It is concluded that the relative size of the flocculus of endocranial casts is an unreliable predictor of locomotor behavior in extinct birds, and probably also pterosaurs and non-avian dinosaurs.
The avian nature of the brain and inner ear of Archaeopteryx
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.
Brain modularity across the theropod–bird transition: testing the influence of flight on neuroanatomical variation
Generalized multi‐regime Ornstein‐Uhlenbeck (OU) models suggest that powered flight does not appear to be a driver of observed variation, reinforcing the hypothesis that the deep history of the avian brain is complex, with nuances still to be discovered.
Deep evolutionary diversification of semicircular canals in archosaurs
The internal cranial anatomy of Champsosaurus (Choristodera: Champsosauridae): Implications for neurosensory function
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.
New Insights Into the Brain, Braincase, and Ear Region of Tyrannosaurs (Dinosauria, Theropoda), with Implications for Sensory Organization and Behavior
Tyrannosaur sensory biology is consistent with their predatory coelurosaurian heritage, with emphasis on relatively quick, coordinated eye and head movements, and probably sensitive low‐frequency hearing; tyrannosaurs apomorphically enhanced their olfactory apparatus.


Vestibular evidence for the evolution of aquatic behaviour in early cetaceans
It is hypothesized that the unparalleled modification of the semicircular canal system represented a key ‘point of no return’ event in early cetacean evolution, leading to full independence from life on land.
Evolution of the Brain and Intelligence
The evidence of the actual evolution of the vertebrate brain is analyzed by reviewing morphological data on endocasts and skeletons of several hundred fossil species and comparing these with living
Comparative review of the human bony labyrinth.
This review compares the bony labyrinth of humans with that of the great apes and 37 other primate species based on data newly acquired with computed tomography combined with previous descriptions, finding that labyrinthine and basicranial shape are interspecifically correlated in the sample, and in most respects the human morphology is consistent with the general trend among primates.
The Osteology of the Reptiles
IN no domain of zoological science have the con tributions of American naturalists been more splendid than in that of vertebrate palaeontology, and in the list of pioneer workers in this domain an
On the Skull, Brain, and Auditory Organ of a New Species of Pterosaurian (Scaphognathus Purdoni), from the Upper Lias near Whitby, Yorkshire
By careful work with the chisel I succeeded in laying bare much more of the skull, and it has proved to be of unexpected value, and, for several reasons, of exceptional interest.
Comparative Vertebrate Neuroanatomy: Evolution and Adaptation
The evolution andorganization of the central nervous system in Vertebrates and theories of Brain Evolution and Variation are summarized.
Zonal organization of the vestibulocerebellum in pigeons (Columba livia): I. Climbing fiber input to the flocculus
The zonal organization of the climbing fiber input to the flocculus of pigeons is investigated and four parasagittal bands spanning both folia IXcd and X consisting of two rVA zones interdigitated with two rH45 zones are compared with the zonal groupings in mammalian species.
  • C. Brochu
  • Environmental Science, Geography
  • 2001
The basic structure of archosaurian phylogeny is understood to include two primary crown-group lineages—one leading to living crocodiles and including a broad diversity of Triassic animals and another leading to dinosaurs.
Head orientation in pigeons: postural, locomotor and visual determinants.
In contrast to their relatively stable head posture during locomotion, the pigeons consistently altered their head orientation when presented with seed targets, apparently to fixate each seed with a small portion of the visual field around the bill tip.
A theoretical and comparative study of the functional dependence of the semicircular canal upon its physical dimensions
  • G. M. Jones, K. Spells
  • Environmental Science
    Proceedings of the Royal Society of London. Series B. Biological Sciences
  • 1963
Measurements of the internal radius (r) and radius of curvature (R) of the endolymphatic canal were made in 87 species, comprising 46 mammals, 17 birds, 17 fishes and 7 reptiles, using specimens, and photographic records of specimens, already available.