Artículos de revistas
Palaeoenvironmental Characterization Of A Crocodilian Nesting Site From The Late Cretaceous Of Brazil And The Evolution Of Crocodyliform Nesting Strategies
Registro en:
Palaeogeography Alaeoclimatology Palaeoecology. Elsevier Science Bv, v. 457, p. 221 - 232, 2016.
0031-0182
1872-616X
WOS:000380598800017
10.1016/j.palaeo.2016.06.020
Autor
Marsola
Julio C. de A.; Batezelli
Alessandro; Montefeltro
Felipe C.; Grellet-Tinner
Gerald; Langer
Max C.
Institución
Resumen
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Despite the vast crocodyliform fossil record, little is known about the reproductive biology and nesting strategies of the extinct members of the group. Here we report a large accumulation of crocodilian fossil eggs from the type locality of the baurusuchid Pissarrachampsa sera. Sedimentary fades and architectural elements of the site support a palaeoenvironmental model with a shallow lacustrine, playa-lake system interacting to ephemeral braided fluvial channels, with aeolian influence and development of sandy soils. The presence of pedogenic calcretes in the palaeosols indicates arid to semi-arid conditions. The crocodilian affinity of the eggs is supported by the thin eggshell which bears wedge-shaped shell units with tabular microstructures. Furthermore, taphonomic data support an autochthonous assemblage of eggs and skeletal remains, hinting at a monotypical stratigraphic horizon and suggesting P. sera as the egg-laying taxon. The repeated pattern of four (eventually five) eggs per clutch at the site demonstrates that P. sera laid fewer eggs compared to modern crocodilians, indicating that k-selected reproductive strategy pattern is pervasive in the fossil record of Notosuchia. In the crocodyliform phylogenetic framework, the k-strategy and the "egg clutch sizes" optimization of Notosuchia is opposite to the strategy with larger clutches consistently occurring in modern Crocodylia and Neosuchia, the sister Glade to Notosuchia. Yet, the lack of data on more early-branching taxa renders unclear which pattern is plesiomorphic for Crocodyliformes as a whole. (C) 2016 Elsevier B.V. All rights reserved. 457 221 232 Laboratorio Nacional de Luz Sincrotron - LNNano/CNPEM [SEM-1667] Sao Paulo Research Foundation (FAPESP - Fundacao de Amparo a Pesquisa do Estado de Sao Paulo) [2010/14797-0, 2013/23114-1, 2010/19787-2, 2013/11358-3, 2014/03825-3] Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)