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[dinosaur] Gregarious behavior in robust Jurassic Ornithopods + two-toed "raptor" tracks + more




Ben Creisler
bcreisler@gmail.com


Some recent papers:


In the new issue of Ichnos:

Laura Piñuela, José C. García-Ramos, Mike Romano & José I. Ruiz-Omeñaca (2016)
First Record of Gregarious Behavior in Robust Medium-Sized Jurassic Ornithopods: Evidence from the Kimmeridgian Trackways of Asturias (N. Spain) and Some General Considerations on Other Medium-Large Ornithopod Tracks in the Mesozoic Record.
 Ichnos 23 (3-4): 298-311 
http://www.tandfonline.com/doi/full/10.1080/10420940.2016.1178640


At least four parallel trackways of medium-sized and robust ornithopods are described from the Upper Jurassic Tereñes tracksite in Asturias (N. Spain). While the tracks and trackways of small and gracile ornithopods are common in the Jurassic record, large ornithopods are very rare in this period. Ornithopod gregarious behavior has been recorded from many Cretaceous ichnoassemblages, but there are few examples from the Jurassic, and these always relate to small individuals. The Asturian tracks are quite different from known ichnogenera, but they are not sufficiently well preserved to propose a new one. Medium-large Jurassic ornithopods with robust feet such as Draconyx or Cumnoria are the best candidates to be the trackmakers.


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Alexander Wagensommer, Marianna Latiano, Helke B. Mocke, Simone D'Orazi Porchetti & Ansgar Wanke (2016)
A Dinosaur Ichnocoenosis from the Waterberg Plateau (Etjo Formation, Lower Jurassic), Namibia.
Ichnos 23 (3-4): 312-321 
http://www.tandfonline.com/doi/full/10.1080/10420940.2016.1168739


About a hundred dinosaur tracks, mostly preserved as isolated footprints, have been recorded at a single site within the borders of the Waterberg National Park, Otjozondjupa Region, north-central Namibia. They are found in an interdune setting within the Lower Jurassic Etjo Formation and represent medium-sized theropods with slender digits and high projection of digit three. From an ichnotaxonomic point of view, the Namibian tracks are intermediate in morphology between Grallator (which is known to occur at other localities within the same Etjo Formation) and Anchisauripus, being otherwise in a size range that is usually considered typical for the latter ichnotaxon or even for Eubrontes. The Waterberg tracks do not match the allometric growth model proposed by Olsen et al. (1998) for the Early Jurassic theropod track assemblage of the North American Connecticut Valley, and they highlight the difficulties of consistently discriminating between theropod ichnotaxa in the Grallator-Anchisauripus-Eubrontes plexus. The Waterberg ichnosite adds important data to our understanding of the ichnological diversity of the Etjo Formation, raising to three the dinosaur localities in Namibia with revised and updated ichnofaunas. The dinosaur ichnofauna from Namibia, of which the Waterberg tracksite is a basic component, shows high ichnotaxonomic similarity with coeval assemblages from the northern hemisphere. This points to an overall homogeneity of the global ichnofaunistic composition, even at lower latitudes.

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Cecilia A. Pirrone & Luis A. Buatois (2016)
Bioeroded Dinosaur Bones: Novel Signatures of Necrophagous Activity in a Cretaceous Continental Environment.
Ichnos 23 (3-4): 340-348
http://www.tandfonline.com/doi/full/10.1080/10420940.2016.1178641


We describe a novel type of arthropod bioerosion trace fossil, Amphifaoichnus seilacheri new igen., new isp., associated with sauropod bones from the Upper Cretaceous (Coniacian–Early Santonian) Plottier Formation of western Argentina. The specimens are preserved in distal-floodplain deposits. The new ichnotaxon consists of predominantly horizontal, unbranched, unlined, elongated tubes, emplaced at the interface of bone and sediment, but penetrating the bone cortical tissue as well. Fill consists of unconsolidated sediment with evenly distributed bone chips in the infill sorted by size. The presence of bone fragments within the structures indicates prior bioerosion of the bone and their subsequent emplacement as part of the trace fill. A coleopteran with a heavily sclerotized body and well-developed biting mouthparts is tentatively inferred as a tracemaker. Amphifaoichnus seilacheri is interpreted as fodinichnion, reflecting the activity of scavengers able to decompose dinosaur carcasses. This ichnotaxon represents a novel ethology and ecological linkage previously undetected in continental ecosystems.

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A new book:

Dinosaur Tracks, The next steps, Indiana University Press

Book contents:

http://www.jstor.org/stable/j.ctt1c5ckcb

With text excepts (click on download to see each)

https://muse.jhu.edu/book/46080

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chapter currently available as a pdf online:

Martin G. Lockley, Jerald D. Harris, Rihui Li, Lida Xing and Torsten van der Lubbe (2016) 
Two–toed tracks through time: on the trail of “raptors” and their allies. 
In Falkingham, P.L., Marty, D., and Richter, A. (eds) Dinosaur Tracks, The next steps, Indiana University Press, 183–200.
http://www.xinglida.net/pdf/Lockley%20et%20al%202016%20two%20toed%20tracks%20IUP%20b%20vol.pdf


The two-toed, or didactyl, tracks of deinonychosaurian dinosaurs, popularly known as “raptors,” are among the most distinctive theropod tracks known. Including the first confirmed report from China in 1994, a total of 16 tracksites have been recognized, all from Cretaceous strata. These include nine Chinese, two Korean, three North American, and two European occurrences. Many of these tracks have been assigned to four ichnogenera: Velociraptorichnus (two ichnospecies), Dromaeopodus, Menglongipus, and Dromaeosauripus (three ichnospecies). Most of the tracks have been attributed to dromaeosaurid theropods, but in the case of the largest sample, from Germany, a troodontid trackmaker is inferred.

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Also, another recent book:

Brian Noble (2016)
ARTICULATING DINOSAURS: A POLITICAL ANTHROPOLOGY.
University of Toronto Press, Scholarly Publishing Division, 512 Pages 51 Images
http://www.utppublishing.com/Articulating-Dinosaurs-A-Political-Anthropology.html

In this remarkable interdisciplinary study, anthropologist Brian Noble traces how dinosaurs and their natural worlds are articulated into being by the action of specimens and humans together. Following the complex exchanges of palaeontologists, museums specialists, film- and media-makers, science fiction writers, and their diverse publics, he witnesses how fossil remains are taken from their partial state and re-composed into astonishingly precise, animated presences within the modern world, with profound political consequences. 

Articulating Dinosaurs examines the resurrecting of two of the most iconic and gendered of dinosaurs.  First Noble traces the emergence of Tyrannosaurus rex (the “king of the tyrant lizards”) in the early twentieth-century scientific, literary, and filmic cross-currents associated with the American Museum of Natural History under the direction of palaeontologist and eugenicist Henry Fairfield Osborn.  Then he offers his detailed ethnographic study of the multi-media, model-making, curatorial, and laboratory preparation work behind the Royal Ontario Museum’s ground-breaking 1990s exhibit of Maiasaura (the “good mother lizard”).  Setting the exhibits at the AMNH and the ROM against each other, Noble is able to place the political natures of T. rex and Maiasaura into high relief and to raise vital questions about how our choices make a difference in what comes to count as “nature.”  An original and illuminating study of science, culture, and museums, Articulating Dinosaurs is a remarkable look at not just how we visualize the prehistoric past, but how we make it palpable in our everyday lives.