INVESTIGADORES
VASSALLO Aldo Ivan
artículos
Título:
Scaling and adaptations of incisors and cheek teeth in caviomorph rodents (Rodentia, Hystricognathi).
Autor/es:
BECERRA, FEDERICO; VASSALLO, ALDO IVÁN; ECHEVERRÍA, ALEJANDRA; CASINOS, ADRIÀ
Revista:
Journal of Morphology
Editorial:
Wiley
Referencias:
Lugar: Chicago; Año: 2012 vol. 273 p. 1150 - 1162
ISSN:
1097-4687
Resumen:
ABSTRACT The South American hystricognath
rodents are one of the most diverse mammalian clades
considering their occupied habitats, locomotor modes
and body sizes. This might have been partly evolved by
diversification of their masticatory apparatus structure
and its ecological commitment, for example, chisel-tooth
digging. In this phylogeny-based comparative study, we
test the relationship between ecological behavior and
mechanical features of their incisors and molariforms.
In 33 species of nine families of caviomorph rodents, we
analyze incisor attributes related to structural stress resistance
and molar features related with grinding
capacity, for example, second moment of inertia and
enamel index (EI) (enamel band length/occlusal surface
area), respectively. Most of these variables scaled isometrically
to body mass, with a strong phylogenetic effect. A
principal component analysis discrimination on the EI
clustered the species according to their geographic distribution.
We presume that selective pressures in
AndeanPatagonian regions, on particular feeding habits
and chisel-tooth digging behaviors, have modeled the
morphological characteristics of the teeth. Subterranean/
burrower ctenomyids, coruros, and plains viscachas
showed the highest bending/torsion strength and anchorage
values for incisors; a simplified enamel pattern
in molariforms would be associated with a better grinding
of the more abrasive vegetation present in more
open and drier biomes. J. Morphol.