info:eu-repo/semantics/article
First toothless platanistoid from the early Miocene of Patagonia: the golden age of diversification of the Odontoceti
Fecha
2020-06Registro en:
Viglino, Mariana; Gaetán, Carlos Maximiliano; Cuitiño, José Ignacio; Buono, Mónica Romina; First toothless platanistoid from the early Miocene of Patagonia: the golden age of diversification of the Odontoceti; Springer; Journal of Mammalian Evolution; 6-2020
1064-7554
CONICET Digital
CONICET
Autor
Viglino, Mariana
Gaetán, Carlos Maximiliano
Cuitiño, José Ignacio
Buono, Mónica Romina
Resumen
Lower Miocene outcrops from Patagonia (Gaiman Formation, Burdigalian) may reveal more clues for the yet unknown aspects for this period in the evolution of odontocetes. Here, we present the first toothless platanistoid dolphin from the lower Miocene of Patagonia, Dolgopolis kinchikafiforo, gen. et sp. nov. The specimen includes an incomplete skull, with no mandibles or earbones, but sufficiently different from other named odontocetes to propose a new genus and species. Phylogenetic analyses indicated it is a platanistoid of uncertain position within the group, and that it shares some homoplastic characters with physeteroids and ziphioids. Given the absence of defined alveoli and teeth and an inferred moderately short and wide rostrum, we interpreted this new species as most likely a capture suction feeder. Based on our phylogenetic hypothesis, the optimization of feeding strategies recovered raptorial feeding as the plesiomorphic method, and convergent evolution of capture suction feeders in at least four lineages. Platanistoids recorded all feeding strategies during the late Oligocene-early Miocene, although raptorial is the predominant method. This suggests a partitioning of the ecological niches in the early phases of platanistoid evolution, as well as a high diversification of feeding methods previously underestimated for this period. Thus, ecological adaptations have a strong evolutionary pressure in odontocetes communities and should be further explored