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[dinosaur] Brain-skull changes from dinosaurs to birds + Allodaposuchus ICZN + Ennatosaurus + Tennessee pterosaur




Ben Creisler
bcreisler@gmail.com


Some recent (and no so recent) mainly non-dino papers:


Matteo Fabbri, Nicolás Mongiardino Koch, Adam C. Pritchard, Michael Hanson, Eva Hoffman, Gabriel S. Bever, Amy M. Balanoff, Zachary S. Morris, Daniel J. Field, Jasmin Camacho, Timothy B. Rowe, Mark A. Norell, Roger M. Smith, Arhat Abzhanov & Bhart-Anjan S. Bhullar (2017)
The skull roof tracks the brain during the evolution and development of reptiles including birds.
Nature Ecology & Evolution (2017)
doi:10.1038/s41559-017-0288-2
https://www.nature.com/articles/s41559-017-0288-2




Major transformations in brain size and proportions, such as the enlargement of the brain during the evolution of birds, are accompanied by profound modifications to the skull roof. However, the hypothesis of concerted evolution of shape between brain and skull roof over major phylogenetic transitions, and in particular of an ontogenetic relationship between specific regions of the brain and the skull roof, has never been formally tested. We performed 3D morphometric analyses to examine the deep history of brain and skull-roof morphology in Reptilia, focusing on changes during the well-documented transition from early reptiles through archosauromorphs, including nonavian dinosaurs, to birds. Non-avialan taxa cluster tightly together in morphospace, whereas Archaeopteryx and crown birds occupy a separate region. There is a one-to-one correspondence between the forebrain and frontal bone and the midbrain and parietal bone. Furthermore, the position of the forebrain–midbrain boundary correlates significantly with the position of the frontoparietal suture across the phylogenetic breadth of Reptilia and during the ontogeny of individual taxa. Conservation of position and identity in the skull roof is apparent, and there is no support for previous hypotheses that the avian parietal is a transformed postparietal. The correlation and apparent developmental link between regions of the brain and bony skull elements are likely to be ancestral to Tetrapoda and may be fundamental to all of Osteichthyes, coeval with the origin of the dermatocranium.


News:

Scientists track the brain-skull transition from dinosaurs to birds

https://news.yale.edu/2017/09/11/scientists-track-brain-skull-transition-dinosaurs-birds

https://phys.org/news/2017-09-scientists-track-brain-skull-transition-dinosaurs.html


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Iván Narváez, Christopher A. Brochu, Ane de Celis, Massimo Delfino, Fernando Escaso, Adán Pérez-García, Márton Rabi and Francisco Ortega (2017)

Case 3743 — Allodaposuchus precedens Nopcsa, 1928 (Crocodyliformes: Eusuchia: Allodaposuchidae): proposed designation of a neotype.

The Bulletin of Zoological Nomenclature 74():95-101. 2017

doi: https://doi.org/10.21805/bzn.v74.a024

http://www.bioone.org/doi/abs/10.21805/bzn.v74.a024




The purpose of this application, under Article 75.5 of the Code, is to set aside all type fixations for the crocodyliform Allodaposuchus precedens Nopcsa, 1928, and to designate a neotype. The type series of A. precedens includes specimens from the Maastrichtian (Late Cretaceous) of Vălioara, housed at the Magyar Állami Földtani Intézet (Hungarian Geological Institute) in Budapest, Hungary. The original material includes several cranial and postcranial elements thought to correspond to the same specimen but the attribution of this set of remains as belonging to one individual cannot be confirmed. Therefore, subsequent papers considered only part of this set, a fragmentary skull table, as the lectotype of A. precedens. Given the recent description of several species closely related to A. precedens and the lack of a combination of exclusive characters that can diagnose the species based on the specimens studied by Nopcsa, we request that the Commission set aside all previous type fixations and designate a neotype for A. precedens. The neotype designation is of utmost importance for the objective identification of this species, which is necessary for future phylogenetic analyses and assessments of crocodyliform diversity.



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Marco Romano, Neil Brocklehurst & Jörg Fröbisch (2017)
The postcranial skeleton of Ennatosaurus tecton (Synapsida, Caseidae).
Journal of Systematic Palaeontology (advance online publication)
doi: http://dx.doi.org/10.1080/14772019.2017.1367729
http://www.tandfonline.com/doi/full/10.1080/14772019.2017.1367729



The postcranial material referable to the Russian caseid Ennatosaurus tecton from the middle Permian is described. Although the cranium has been recently restudied in detail, the descriptions currently available for the postcranial skeleton are essentially limited to the original short account on the holotype provided by Efremov in 1956. The postcranium of Ennatosaurus is informative with respect to both taxonomy and phylogeny, with autapomorphic characters present particularly in the vertebral column. In addition to the anatomical description of the elements presented here, eight principal component analyses were conducted to investigate the position of the various osteological elements of Ennatosaurus within caseid morphospace. The inclusion of members of all major groups of ‘pelycosaurs’ and selected outgroup taxa allowed us to make more extensive preliminary inferences regarding postcranial morphospace occupation of these basal synapsids for each individually considered bone. The analysis revealed a major decoupling among the morphospaces of stylopodial and zeugopodial elements, with femora and humeri showing a shared common pattern, and a wider overlap in their respective morphospace. Conversely, the ulnae, radii, tibiae and fibulae show well-separated regions of morphospace in the different clades, indicating their potential importance, not only for functional and biomechanical studies, but also for taxonomic differentiation. Finally, a 3D photogrammetric model of the mounted specimen at the Paleontological Institute in Moscow forms the basis for the first in vivo reconstruction of Ennatosaurus tecton, providing a potentially realistic picture of the Russian caseid in life.


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A paper from last year not yet mentioned. I don't have a direct weblink to the article, however.

The journal webpage is here:

http://almnh.ua.edu/bulletin-of-the-alabama-museum-of-natural-history.html




Harrell, T. Lynn Jr.; Gibson, Michael A.; Langston, Wann Jr. (2016)

A cervical vertebra of Arambourgiania philadelphiae (Pterosauria, Azhdarchidae) from the Late Campanian micaceous facies of the Coon Creek Formation in McNairy County, Tennessee, USA.

Bulletin of the Alabama Museum of Natural History 33: 94–103

 

The occurrence of Arambourgiana remains in marine deposts in Tennessee shows that giant azhdarchids were capable of long distances across Laurasia. Because more than one azhdarchoid occurs in the Javelina Formation and Arambourgiana is known only from cervical vertebra and partial wing remains, it is possible that the TMM 42489 might represent Arambourgiana because the wingspans of giant azhdarchids were big enough to facilitate long distances over the Northern Hemisphere.