Dental Occlusion in a 260-Million-Year-Old Therapsid with Saber Canines from the Permian of Brazil

@article{Cisneros2011DentalOI,
  title={Dental Occlusion in a 260-Million-Year-Old Therapsid with Saber Canines from the Permian of Brazil},
  author={Juan Carlos Cisneros and Fernando Abdala and Bruce S. Rubidge and Paula Dentzien-Dias and Ana de Oliveira Bueno},
  journal={Science},
  year={2011},
  volume={331},
  pages={1603 - 1605}
}
Tiarajudens extends the date of dental occlusion and suggests why the members of this Permian group were such diverse and successful herbivores. Anomodonts, a group of herbivorous therapsid “mammal-like reptiles,” were the most abundant tetrapods of the Permian. We present a basal anomodont from South America, a new taxon that has transversally expanded palatal teeth and long saber canines. The function of the saber teeth is unknown, but probable uses include deterring attack from predators and… 
On Dental Occlusion and Saber Teeth
TLDR
A new therapsid fossil from South America is described, Tiarajudens eccentricus, which displays a unique dentition, including broad chewing teeth on the palate and a pair of extremely long saber canines, which provides novel insights into early tooth differentiation in synapsids and into the evolution of herbivory (plant eating) and its accompanying complex social interactions.
Evolution of facial innervation in anomodont therapsids (Synapsida): Insights from X‐ray computerized microtomography
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The pattern of innervation of the anomodont “beak” is more similar to that in chelonians than in birds, and the presence or absence of tusks and postcanine teeth are often accompanied by corresponding variations of the rami innervating the caniniform process and the alveolar region.
Amniote Dental Histology, Development, and Variation: Perspectives From the Fossil Record
TLDR
By comparing histological sections of a large sample of modern and extinct amniotes, this thesis establishes tooth tissue homology across several major amniote groups and shows that even mammals and crocodilians possess the most complex forms of tooth attachment.
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The first dicynodont reported for the Permian of South America is described in detail here. The specimen consists of a partial skull and associated lower jaws, collected from the Serra do Cadeado
Tiarajudens eccentricus and Anomocephalus africanus, two bizarre anomodonts (Synapsida, Therapsida) with dental occlusion from the Permian of Gondwana
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The outsized, blade-like caniniforms of the herbivorous Tiarajudens allow several non-exclusive ecological interpretations, among which the authors favour intraspecific display or combat.
Bone microstructure of the pareiasaur Provelosaurus americanus from the Middle Permian of southern Brazil
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New Dicynodonts (Therapsida, Anomodontia) and Updated Tetrapod Stratigraphy of the Permian Ruhuhu Formation (Songea Group, Ruhuhu Basin) of Southern Tanzania
ABSTRACT Permian tetrapod fossils were discovered in the Tanzanian Ruhuhu Formation in 1963, but they have received far less attention than the tetrapods of the overlying Usili (formerly Kawinga)
Evidence of strong stabilizing effects on the evolution of boreoeutherian (Mammalia) dental proportions
TLDR
Boreoeutherian postcanine dental proportions sampled in this study carry conserved phylogenetic signal and are not associated with variation in diet, providing further evidence that dental proportions may be slower to change than is dietary specialization.
The evolution of the synapsid tusk: insights from dicynodont therapsid tusk histology
TLDR
The evolution of an ever-growing dentition, such as a tusk, is predicated on the evolution of significantly reduced tooth replacement and a permanent soft-tissue attachment, which helps to explain why tusks are restricted to this clade among extant vertebrates.
The Brazilian Pareiasaur Revisited
Provelosaurus americanus is the only known representative of the Pareiasauria in the Americas. This mid-size pareiasaur from the Rio do Rasto Formation of southern Brazil has been traditionally
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