An ecomorphological analysis of forelimb musculo-tendinous system in sigmodontine rodents (Rodentia, Cricetidae, Sigmodontinae)

CARRIZO LUZ V; M.J. TULLI; ABDALA, V

JOURNAL OF MAMMALOGY

ALLIANCE COMMUNICATIONS GROUP DIVISION ALLEN PRESS

Lugar: Lawrence; Año: 2014 vol. 95 p. 843 - 854

0022-2372

The central tenet of ecomorphological theory holds that there is a correlation between design(morphological traits) and ecology of organisms. The Sigmodontine rodents (Rodentia,Cricetidae, Sigmodontinae) exhibit a remarkably high diversity of locomotory types, allowing them to occupy different environments and ecological niches. The main aims of this work were to test whether the internal morphology of the forelimb of 26 species of sigmodontine, as assessed through the analysis of 32 characters, differs among taxa that exhibit different types of locomotion (saltatorial, ambulatory, fossorial, scansorial, and natatorial), and whether such patterns can be explained also by the phylogenetic affinities of the species examined. Indeed,our results show the effect of phylogeny in explaining an important part of the observed morphological variation in sigmodontine rodents. This phylogenetic inertia could be responsible for the homogeneity in the overall muscle forelimb morphology in this group. This is the first time that these types of variables are considered in an ecomorphological investigation of these taxa. Our result revealed that tendinous variables seem to be better descriptors of locomotory types than muscular ones. Twelve tendinous variables of the forelimb present in fossorial and scansorial sigmodontines point out interesting differences between these two locomotory types of organisms. Ambulatory, saltatorial and natatorial taxa showed no particular morphological variables associated with their locomotory types. Additionally, we observed that fossorial and natatorial taxa exhibit a bigger anatomical cross-sectional area of three selected muscles (triceps longus, extensor digitorum, flexor digitorum profundus) than that of the taxa with other locomotory types.