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Sedimentology and ichnology of the Mafube dinosaur track site (Lower Jurassic, eastern Free State, South Africa): a report on footprint preservation and palaeoenvironment

Footprint morphology (e.g., outline shape, depth of impression) is one of the key diagnostic features used in the interpretation of ancient vertebrate tracks. Over 80 tridactyl tracks, confined to the same bedding surface in the Lower Jurassic Elliot Formation at Mafube (eastern Free State, South Af...

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Autores principales: Sciscio, Lara, Bordy, Emese M., Reid, Mhairi, Abrahams, Miengah
Formato: Online Artículo Texto
Lenguaje:English
Publicado: PeerJ Inc. 2016
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5012264/
https://www.ncbi.nlm.nih.gov/pubmed/27635310
http://dx.doi.org/10.7717/peerj.2285
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author Sciscio, Lara
Bordy, Emese M.
Reid, Mhairi
Abrahams, Miengah
author_facet Sciscio, Lara
Bordy, Emese M.
Reid, Mhairi
Abrahams, Miengah
author_sort Sciscio, Lara
collection PubMed
description Footprint morphology (e.g., outline shape, depth of impression) is one of the key diagnostic features used in the interpretation of ancient vertebrate tracks. Over 80 tridactyl tracks, confined to the same bedding surface in the Lower Jurassic Elliot Formation at Mafube (eastern Free State, South Africa), show large shape variability over the length of the study site. These morphological differences are considered here to be mainly due to variations in the substrate rheology as opposed to differences in the trackmaker’s foot anatomy, foot kinematics or recent weathering of the bedding surface. The sedimentary structures (e.g., desiccation cracks, ripple marks) preserved in association with and within some of the Mafube tracks suggest that the imprints were produced essentially contemporaneous and are true dinosaur tracks rather than undertracks or erosional remnants. They are therefore valuable not only for the interpretation of the ancient environment (i.e., seasonally dry river channels) but also for taxonomic assessments as some of them closely resemble the original anatomy of the trackmaker’s foot. The tracks are grouped, based on size, into two morphotypes that can be identified as Eubrontes-like and Grallator-like ichnogenera. The Mafube morphotypes are tentatively attributable to large and small tridactyl theropod trackmakers, possibly to Dracovenator and Coelophysis based on the following criteria: (a) lack of manus impressions indicative of obligate bipeds; (b) long, slender-digits that are asymmetrical and taper; (c) often end in a claw impression or point; and (d) the tracks that are longer than broad. To enable high-resolution preservation, curation and subsequent remote studying of the morphological variations of and the secondary features in the tracks, low viscosity silicone rubber was used to generate casts of the Mafube tracks.
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spelling pubmed-50122642016-09-15 Sedimentology and ichnology of the Mafube dinosaur track site (Lower Jurassic, eastern Free State, South Africa): a report on footprint preservation and palaeoenvironment Sciscio, Lara Bordy, Emese M. Reid, Mhairi Abrahams, Miengah PeerJ Environmental Sciences Footprint morphology (e.g., outline shape, depth of impression) is one of the key diagnostic features used in the interpretation of ancient vertebrate tracks. Over 80 tridactyl tracks, confined to the same bedding surface in the Lower Jurassic Elliot Formation at Mafube (eastern Free State, South Africa), show large shape variability over the length of the study site. These morphological differences are considered here to be mainly due to variations in the substrate rheology as opposed to differences in the trackmaker’s foot anatomy, foot kinematics or recent weathering of the bedding surface. The sedimentary structures (e.g., desiccation cracks, ripple marks) preserved in association with and within some of the Mafube tracks suggest that the imprints were produced essentially contemporaneous and are true dinosaur tracks rather than undertracks or erosional remnants. They are therefore valuable not only for the interpretation of the ancient environment (i.e., seasonally dry river channels) but also for taxonomic assessments as some of them closely resemble the original anatomy of the trackmaker’s foot. The tracks are grouped, based on size, into two morphotypes that can be identified as Eubrontes-like and Grallator-like ichnogenera. The Mafube morphotypes are tentatively attributable to large and small tridactyl theropod trackmakers, possibly to Dracovenator and Coelophysis based on the following criteria: (a) lack of manus impressions indicative of obligate bipeds; (b) long, slender-digits that are asymmetrical and taper; (c) often end in a claw impression or point; and (d) the tracks that are longer than broad. To enable high-resolution preservation, curation and subsequent remote studying of the morphological variations of and the secondary features in the tracks, low viscosity silicone rubber was used to generate casts of the Mafube tracks. PeerJ Inc. 2016-08-23 /pmc/articles/PMC5012264/ /pubmed/27635310 http://dx.doi.org/10.7717/peerj.2285 Text en ©2016 Sciscio et al. http://creativecommons.org/licenses/by/4.0/ This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/) , which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ) and either DOI or URL of the article must be cited.
spellingShingle Environmental Sciences
Sciscio, Lara
Bordy, Emese M.
Reid, Mhairi
Abrahams, Miengah
Sedimentology and ichnology of the Mafube dinosaur track site (Lower Jurassic, eastern Free State, South Africa): a report on footprint preservation and palaeoenvironment
title Sedimentology and ichnology of the Mafube dinosaur track site (Lower Jurassic, eastern Free State, South Africa): a report on footprint preservation and palaeoenvironment
title_full Sedimentology and ichnology of the Mafube dinosaur track site (Lower Jurassic, eastern Free State, South Africa): a report on footprint preservation and palaeoenvironment
title_fullStr Sedimentology and ichnology of the Mafube dinosaur track site (Lower Jurassic, eastern Free State, South Africa): a report on footprint preservation and palaeoenvironment
title_full_unstemmed Sedimentology and ichnology of the Mafube dinosaur track site (Lower Jurassic, eastern Free State, South Africa): a report on footprint preservation and palaeoenvironment
title_short Sedimentology and ichnology of the Mafube dinosaur track site (Lower Jurassic, eastern Free State, South Africa): a report on footprint preservation and palaeoenvironment
title_sort sedimentology and ichnology of the mafube dinosaur track site (lower jurassic, eastern free state, south africa): a report on footprint preservation and palaeoenvironment
topic Environmental Sciences
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5012264/
https://www.ncbi.nlm.nih.gov/pubmed/27635310
http://dx.doi.org/10.7717/peerj.2285
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