Research paper

First functional morphology comparison between two Miocene cricetid mandibles


PATRICIA MARÍA CARRO-RODRÍGUEZ
Department of Geodynamics, Stratigraphy and Palaeontology (GEODESPAL), Universidad Complutense de Madrid, Madrid, Spain.

Sedimentary Geology and Environmental Change, Geosciences Institute (CSIC, UCM), Madrid, Spain. patcarro@ucm.es
Corresponding author

PALOMA LÓPEZ-GUERRERO
Department of Geodynamics, Stratigraphy and Palaeontology (GEODESPAL), Universidad Complutense de Madrid, Madrid, Spain. palomalopez@geo.ucm.es

JÉRÔME PRIETO
Department of Earth and Environmental Science, Palaeontology & Geobiology, Ludwig-Maximilians-University Munich, Richard-Wagner-Str. 10, 80333 Munich, Germany. j.prieto@web.de

MARÍA ÁNGELES ÁLVAREZ-SIERRA
Department of Geodynamics, Stratigraphy and Palaeontology (GEODESPAL), Universidad Complutense de Madrid, Madrid, Spain

Sedimentary Geology and Environmental Change, Geosciences Institute (CSIC, UCM), Madrid, Spain. masierra@ucm.es

PABLO PELÁEZ-CAMPOMANES
Department of Paleobiology, Museo Nacional de Ciencias Naturales, CSIC. C/ José Gutiérrez Abascal 2, 28006 Madrid, Spain. pablopelaez@mncn.csic.es


ABSTRACT

Geometric morphometric allows characterizing complex morphologies in order to quantify the geometry of the structure and facilitate comparisons. It allows performing methods analysing differentiation pattern based on variance, such as the Principal Component Analysis (PCA). For that reason, it has been chosen as the method to analyse the mandibles of two extinct species of cricetids rodents: Cricetodon aff. aureus and Megacricetodon minor from the MN6, middle Miocene from Goldberg and Steinberg (Germany). We performed a digitisation of 18 landmarks that includes the most relevant characteristics of these mandibles. We also performed a measure of the mechanical advantage and potential of the mandibles. In that way, we have been able to quantify notorious morphological differences on the angular and condylar processes and the lower masseter Geometric morphometric allows characterizing complex morphologies in order to quantify the geometry of the structure and facilitate comparisons. It allows performing methods analysing differentiation pattern based on variance, such as the Principal Component Analysis (PCA). For that reason, it has been chosen as the method to analyse the mandibles of two extinct species of cricetids rodents: Cricetodon aff. aureus and Megacricetodon minor from the MN6, middle Miocene from Goldberg and Steinberg (Germany). We performed a digitisation of 18 landmarks that includes the most relevant characteristics of these mandibles. We also performed a measure of the mechanical advantage and potential of the mandibles. In that way, we have been able to quantify notorious morphological differences on the angular and condylar processes and the lower masseter insertion and establish significant differences among the biomechanical behaviour of the mandibles. Later, we can relate the morphological and biomechanical information with speed and force biting.


Key words: Cricetodon, Megacricetodon, geometric morphometric, middle Miocene, Germany

How to cite: Carro-Rodríguez, P.M., López-Guerrero, P., Prieto, J., Álvarez-Sierra, M.Á. & Peláez-Campomanes, P. 2020. First functional morphology comparison between two Miocene cricetid mandibles. Spanish Journal of Palaeontology, 35 (2), 167-176.

Received 27 November 2019, Accepted 18 May 2020, Published 31 December 2020

https://doi.org/10.7203/sjp.35.2.18480