FUNCTIONAL SUBDIVISION OF THE VERTEBRAL COLUMN IN FOUR SOUTH AMERICAN DOLPHINS

MORA, MC; GONZÁLEZ JOSÉ, ROLANDO; MARCHESI, MC; BOY, C; CRESPO, E; GOODALL, RNP

MASTOZOOLOGí­A NEOTROPICAL

UNIDAD DE ZOOLOGÍA Y ECOLOGÍA ANIMAL, INSTITUTO ARGENTINO DE INVESTIGACIÓN DE LAS ZONAS ARIDAS, CRICYT, CONICET

Lugar: Mendoza; Año: 2019

0327-9383

Description and functional interpretation of morphological variation in the dolphin column canbe facilitated by recognizing structural units. This information offers important clues to the proportion of thecolumn involved in the oscillation and displacement of the flukes, and how swimming style can vary amongspecies. Thus, the morphological characterization and functional subdivision of the vertebral column is of keyimportance to gain insights into the locomotor performance of cetacean species occurring in different environments.We employed traditional morphometrics to establish the functional subdivision of the vertebral column ofCommerson?s dolphin (Cephalorhynchus commersonii), a coastal species, and the dusky dolphin (Lagenorhynchusobscurus), a shelf species. These species are closely related, and some of them are partially sympatric. We alsocompared the obtained results against information previously reported by Marchesi et al (2017) on Peale?sdolphin (Lagenorhynchus australis), a coastal species, and the hourglass dolphin (Lagenorhynchus cruciger), anoceanic species. These results bring further support to our hypothesis that coastal species have morphologicaltraits associated with higher flexibility, whilst platform and oceanic species have features associated with higherstability in a greater proportion of their column.