Donato Costamagna , Brenda S. Ferrero , Federico Giri , Ana María Ribeiro
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引用次数: 0
Abstract
This study aims to assess shape and size variations in lower molars (m1-m3) of Toxodon platensis Owen across diverse South-American regions: northern Pampa, Mesopotamia, northwestern Argentina (NWA), southwestern Uruguay, and southern Brazil. We examined 102 specimens, capturing 20 landmarks for each molar. Principal component analyses were used for shape analysis, and geographic origin relationships were explored through cluster analysis. Centroid size (CS) was analyzed with ANOVA. The shape of T. platensis molars differed among different populations in each geographic region. Molars from NWA exhibited a slenderer shape, whereas Mesopotamia specimens displayed more robust trigonids. Northern Pampa and southwestern Uruguay molars were the most similar in shape, and the molars of the populations in southern Brazil showed more curved morphologies. CS was similar among the different populations of T. platensis, which suggests a probability of similar food particle fracture and processing. On the other hand, when observing shape variations as a result of diet, it can be concluded that the shape changes observed in different geographic areas could be related to the type of vegetation consumed by various T. platensis populations.
期刊介绍:
Geobios publishes bimonthly in English original peer-reviewed articles of international interest in any area of paleontology, paleobiology, paleoecology, paleobiogeography, (bio)stratigraphy and biogeochemistry. All taxonomic groups are treated, including microfossils, invertebrates, plants, vertebrates and ichnofossils.
Geobios welcomes descriptive papers based on original material (e.g. large Systematic Paleontology works), as well as more analytically and/or methodologically oriented papers, provided they offer strong and significant biochronological/biostratigraphical, paleobiogeographical, paleobiological and/or phylogenetic new insights and perspectices. A high priority level is given to synchronic and/or diachronic studies based on multi- or inter-disciplinary approaches mixing various fields of Earth and Life Sciences. Works based on extant data are also considered, provided they offer significant insights into geological-time studies.