Non-tribosphenic Gondwanan mammals and the alternative development of molars with a reversed triangle cusp pattern

Several lineages of non-holotherian Gondwanan mammals developed complex, tribosphenic-like molars, but not tribosphenic occlusion. The reversed triangle occlusal pattern, characteristic of holotherian lineages leading to tribosphenic occlusion, could have been acquired without a cusp rotation proces...

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Autores principales: Pascual, Rosendo, Goin, Francisco Javier
Formato: Articulo
Lenguaje:Inglés
Publicado: 2001
Materias:
Paleontología
Mammals
Monotremata
Gondwanatheria
Gondwana
Molar pattern
Evolution
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/116005
https://www.peapaleontologica.org.ar/index.php/peapa/article/view/235
Aporte de:
SEDICI (UNLP) de Universidad Nacional de La Plata
id I19-R120-10915-116005
record_format dspace
institution Universidad Nacional de La Plata
institution_str I-19
repository_str R-120
collection SEDICI (UNLP)
language Inglés
topic Paleontología
Mammals
Monotremata
Gondwanatheria
Gondwana
Molar pattern
Evolution
spellingShingle Paleontología
Mammals
Monotremata
Gondwanatheria
Gondwana
Molar pattern
Evolution
Pascual, Rosendo
Goin, Francisco Javier
Non-tribosphenic Gondwanan mammals and the alternative development of molars with a reversed triangle cusp pattern
topic_facet Paleontología
Mammals
Monotremata
Gondwanatheria
Gondwana
Molar pattern
Evolution
description Several lineages of non-holotherian Gondwanan mammals developed complex, tribosphenic-like molars, but not tribosphenic occlusion. The reversed triangle occlusal pattern, characteristic of holotherian lineages leading to tribosphenic occlusion, could have been acquired without a cusp rotation process. A review of the molar structure in primitive monotreme prototherians and gondwanathere allotherians suggests that a tricuspid pattern could have been accomplished by expansion of cingula, elevation of their cusps, and connection by ridges of two of the latter to one of the original ones, leading to a triangular pattern in some, or all, their molars. This cusp and ridge arrangement is already outlined in the lower cheekteeth of Steropodon galmani Archer et al., the oldest (Early Cretaceous) and most primitive Platypoda so far known. Similarly, one isolated lower molariform of the primitive gondwanathere Ferugliotherium windhauseni Bonaparte (Late Cretaceous) shows its anterolabial cusp connected by two ridges to two lingual cusps, forming a V-shaped, trigonid-like structure
format Articulo
Articulo
author Pascual, Rosendo
Goin, Francisco Javier
author_facet Pascual, Rosendo
Goin, Francisco Javier
author_sort Pascual, Rosendo
title Non-tribosphenic Gondwanan mammals and the alternative development of molars with a reversed triangle cusp pattern
title_short Non-tribosphenic Gondwanan mammals and the alternative development of molars with a reversed triangle cusp pattern
title_full Non-tribosphenic Gondwanan mammals and the alternative development of molars with a reversed triangle cusp pattern
title_fullStr Non-tribosphenic Gondwanan mammals and the alternative development of molars with a reversed triangle cusp pattern
title_full_unstemmed Non-tribosphenic Gondwanan mammals and the alternative development of molars with a reversed triangle cusp pattern
title_sort non-tribosphenic gondwanan mammals and the alternative development of molars with a reversed triangle cusp pattern
publishDate 2001
url http://sedici.unlp.edu.ar/handle/10915/116005
https://www.peapaleontologica.org.ar/index.php/peapa/article/view/235
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AT goinfranciscojavier nontribosphenicgondwananmammalsandthealternativedevelopmentofmolarswithareversedtrianglecusppattern
bdutipo_str Repositorios
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