Locomotion in some small to medium-sized mammals: a geometric morphometric analysis of the penultimate lumbar vertebra, pelvis and hindlimbs

ÁLVAREZ, ALICIA; ERCOLI, MARCOS DARÍO; PREVOSTI, FRANCISCO JUAN

ZOOLOGY

ELSEVIER GMBH

Año: 2013 vol. 116 p. 356 - 371

0944-2006

We assessed the influence of a variety of aspects of locomotion and ecology including gait and locomotortypes, maximal running speed, home range, and body size on postcranial shape variation in small tomedium-sized mammals, employing geometric morphometric analysis and phylogenetic comparativemethods. The four views analyzed, i.e., dorsal view of the penultimate lumbar vertebra, lateral view ofthe pelvis, posterior view of the proximal femur and proximal view of the tibia, showed clear phylogeneticsignal and interesting patterns of association with movement. Variation in home range size was relatedto some tibia shape changes, while speed was associated with lumbar vertebra, pelvis and tibia shapechanges. Femur shape was not related to any locomotor variables. In both locomotor type and high-speedgait analyses, locomotor groups were distinguished in both pelvis and tibia shape analyses. These resultssuggest that adaptations to both typical and high-speed gaits could explain a considerable portion ofthe shape of those elements. In addition, lumbar vertebra and tibia showed non-significant relationshipswith body mass, which suggests that they might be used in morpho-functional analyses and locomotorinferences on fossil taxa, with little or no bias for body size. Lastly, we observed morpho-functionalconvergences among several mammalian taxa and detected some taxa that achieve similar locomotorfeatures following different morphological paths.