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[dinosaur] Bird and alligator brains + Cretaceous bipedal lizard tracks + Normandy Jurassic marine reptiles (free pdfs)




Ben Creisler
bcreisler@gmail.com



Some recent non-dino papers with free pdfs:



Steven D. Briscoe, Caroline B. Albertin, Joanna J. Rowell & Clifton W. Ragsdale (2018)
Neocortical Association Cell Types in the Forebrain of Birds and Alligators.
Current Biology (advance online publication)
DOI: https://doi.org/10.1016/j.cub.2018.01.036
http://www.cell.com/current-biology/fulltext/S0960-9822(18)30038-1
Free pdf:
http://www.cell.com/current-biology/pdf/S0960-9822(18)30038-1.pdf


Highlights

RNA-seq identifies neocortical intratelencephalic (IT) neurons in the avian brain
IT neurons populate the avian mesopallium but not the nidopallium or the arcopallium
Gene _expression_ demonstrates IT cell types in the alligator dorsal telencephalon
IT neurons were present in the last common ancestor of birds and mammals

Summary

The avian dorsal telencephalon has two vast territories, the nidopallium and the mesopallium, both of which have been shown to contribute substantially to higher cognitive functions. From their connections, these territories have been proposed as equivalent to mammalian neocortical layers 2 and 3, various neocortical association areas, or the amygdala, but whether these are analogies or homologies by descent is unknown. We investigated the molecular profiles of the mesopallium and the nidopallium with RNA-seq. Gene _expression_ experiments established that the mesopallium, but not the nidopallium, shares a transcription factor network with the intratelencephalic class of neocortical neurons, which are found in neocortical layers 2, 3, 5, and 6. Experiments in alligators demonstrated that these neurons are also abundant in the crocodilian cortex and form a large mesopallium-like structure in the dorsal ventricular ridge. Together with previous work, these molecular findings indicate a homology by descent for neuronal cell types of the avian dorsal telencephalon with the major excitatory cell types of mammalian neocortical circuits: the layer 4 input neurons, the deep layer output neurons, and the multi-layer intratelencephalic association neurons. These data raise the interesting possibility that avian and primate lineages evolved higher cognitive abilities independently through parallel expansions of homologous cell populations.


News:


Birds and primates share brain cell types linked to intelligence


https://phys.org/news/2018-02-birds-primates-brain-cell-linked.html


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Hang-Jae Lee, Yuong-Nam Lee, Anthony R. Fiorillo & Junchang LÃ (2018)
Lizards ran bipedally 110 million years ago.
Scientific Reports 8, Article number: 2617 (2018)
doi:10.1038/s41598-018-20809-z
https://www.nature.com/articles/s41598-018-20809-z


Four heteropod lizard trackways discovered in the Hasandong Formation (Aptian-early Albian), South Korea assigned to Sauripes hadongensis, n. ichnogen., n. ichnosp., which represents the oldest lizard tracks in the world. Most tracks are pes tracks (Nâ=â25) that are very small, average 22.29âmm long and 12.46âmm wide. The pes tracks show "typical" lizard morphology as having curved digit imprints that progressively increase in length from digits I to IV, a smaller digit V that is separated from the other digits by a large interdigital angle. The manus track is 19.18âmm long and 19.23âmm wide, and shows a different morphology from the pes. The predominant pes tracks, the long stride length of pes, narrow trackway width, digitigrade manus and pes prints, and anteriorly oriented long axis of the fourth pedal digit indicate that these trackways were made by lizards running bipedally, suggesting that bipedality was possible early in lizard evolution.\\

News:

https://theconversation.com/footprint-fossils-suggest-lizards-have-been-running-on-two-feet-for-110m-years-91865

https://phys.org/news/2018-02-legs-good-tracks-lizard-bipedalism.html


====


Arnaud BrignonÂ(2018)
Contexte historique de la collection FÃlix de Roissy (1771-1843) de reptiles marins jurassiques des Vaches Noires.Â
[Historical context of FÃlix de Roissy (1771-1843)'s collection of marine reptiles from the Jurassic of Vaches Noires.]Â
Geodiversitas 40(2): 43-68 (in French)
https://doi.org/10.5252/geodiv
http://sciencepress.mnhn.fr/en/periodiques/geodiversitas/40/2

pdf:

http://sciencepress.mnhn.fr/sites/default/files/articles/pdf/geo-40-2-2018-arnaud_brignon_0.pdf




FÃlix de Roissyâs collection is one of the very few historical collections of Jurassic reptiles from Normandy put together during the first half of the nineteenth century, still preserved today. This article presents the biography of this Parisian whose family history is closely linked to Villers-sur-Mer. His frequent visits to his cousin and his daughter, the wife of Raoul PÃris dâIllins, mayor of this town, offered him the opportunity to gather many fossils from the Vaches Noires cliffs, including remains of marine reptiles (Ichthyosauria, Plesiosauria, Thallatosuchia). A few specimens were offered to the MusÃum dâHistoire naturelle (Paris) by FÃlix de Roissy, and after his death, by his widow, Anne Marie de Roissy, nÃe dâOutremont. The rest of the de Roissyâs collection was finally bought by the French Government on behalf of the Museum in 1847. The de Roissyâs collection of Jurassic reptiles from the Vaches Noire, still kept in the MusÃum national dâHistoire naturelle (Paris), is particularly noteworthy. Some of these marine reptile remains were studied by the famous anatomist Henri Marie Ducrotay Blainville with whom FÃlix de Roissy had close friendship. In the 1860s, some of these specimens, including the lectotypes of Metriorhynchus superciliosus (Blainville in J.-A. Eudes-Deslongchamps, 1852) and Steneosaurus edwardsi E. Eudes-Deslongchamps, 1868, were also studied and described by EugÃne Eudes-Deslongchamps.





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