EVOLUCIÓN DE LA ONTOGENIA CRANEANA EN CANIDOS DE SUDAMÉRICA

SEGURA, VALENTINA

Congreso; Congreso Iberoamericano de Morfometría Geométrica; 2020

Universidad Católica de Maule

TheSouth American Canids are endemic to the region and form a monophyletic cladesupported by molecular and morphological data, with the exception of Urocyon cinereoargenteus, which is atypical North American form. South American canids occur in almost allenvironments in the continent, and exhibit diet diversity and large sizevariation. Here we analyzed the skull ontogeny by applying 3D geometricmorphometric techniques, in a well-represented sample of South American canids,with the aim of exploring the variation in cranial size and shape as well asevolutionary patterns of such variation. The sample consisted of 1227 crania ofthe 11 living species of South American canids and 92 crania of Canis lupus and Vulpes vulpes, which were considered as out-groups. South Americancanids exhibited similar shape and diet (they are mostly omnivorous), whichimplies similar mechanical commitments, which are reflected in their almostuniform skulls. However, it is possible that cranial similarity is related to ashared evolutionary history with a short time of divergence. Speothos venaticus differed in itsontogenetic trajectory, with the difference being stronger between adults ofthis species and the remaining canids. The skull configuration is consistentwith the hyper-carnivorous diet. In the case of Chrysocyon brachyurus, size plays an important role in thestructure of the skull, giving rise to remarkable morphological differencesfrom other species, although in terminal stages of its ontogeny.