Publications des scientifiques de l'IRD

Salas-Gismondi R., Flynn J. J., Baby Patrice, Tejada-Lara J. V., Wesselingh F. P., Antoine P. O. (2015). A Miocene hyperdiverse crocodylian community reveals peculiar trophic dynamics in proto-Amazonian mega-wetlands. Proceedings of the Royal Society B-Biological Sciences, 282 (1804), p. art. 20142490 [10 p.]. ISSN 0962-8452.

Titre du document
A Miocene hyperdiverse crocodylian community reveals peculiar trophic dynamics in proto-Amazonian mega-wetlands
Année de publication
2015
Type de document
Article référencé dans le Web of Science WOS:000350797400004
Auteurs
Salas-Gismondi R., Flynn J. J., Baby Patrice, Tejada-Lara J. V., Wesselingh F. P., Antoine P. O.
Source
Proceedings of the Royal Society B-Biological Sciences, 2015, 282 (1804), p. art. 20142490 [10 p.] ISSN 0962-8452
Amazonia contains one of the world's richest biotas, but origins of this diversity remain obscure. Onset of the Amazon River drainage at approximately 10.5 Ma represented a major shift in Neotropical ecosystems, and proto-Amazonian biotas just prior to this pivotal episode are integral to understanding origins of Amazonian biodiversity, yet vertebrate fossil evidence is extraordinarily rare. Two new species-rich bonebeds from late Middle Miocene proto-Amazonian deposits of northeastern Peru document the same hyper-diverse assemblage of seven co-occurring crocodylian species. Besides the large-bodied Purussaurus and Mourasuchus, all other crocodylians are new taxa, including a stem caiman-Gnatusuchus pebasensis-bearing a massive shovel-shaped mandible, procumbent anterior and globular posterior teeth, and a mammal-like diastema. This unusual species is an extreme exemplar of a radiation of small caimans with crushing dentitions recording peculiar feeding strategies correlated with a peak in proto-Amazonian molluscan diversity and abundance. These faunas evolved within dysoxic marshes and swamps of the long-lived Pebas Mega-Wetland System and declined with inception of the transcontinental Amazon drainage, favouring diversification of longirostrine crocodylians and more modern generalist-feeding caimans. The rise and demise of distinctive, highly productive aquatic ecosystems substantially influenced evolution of Amazonian biodiversity hotspots of crocodylians and other organisms throughout the Neogene.
Plan de classement
Sciences du milieu [021] ; Ecologie, systèmes aquatiques [036] ; Géologie et formations superficielles [064] ; Etudes, transformation, conservation du milieu naturel [082]
Description Géographique
PEROU ; AMAZONIE
Localisation
Fonds IRD [F B010064020]
Identifiant IRD
fdi:010064020
Contact