info:eu-repo/semantics/article
Shell Area-To-Volume Ratio in Ammonoids
Fecha
2020-07Registro en:
Parent, Horacio; Bejas, Matias Hector; Greco, Andres Francisco; Shell Area-To-Volume Ratio in Ammonoids; Palaeontological Society of Japan; Paleontological Research; 24; 3; 7-2020; 216-225
1342-8144
CONICET Digital
CONICET
Autor
Parent, Horacio
Bejas, Matias Hector
Greco, Andres Francisco
Resumen
The external area-to-volume ratio of the ammonite shell has been held to be related to morphology but never evaluated quantitatively. A dimensionless ratio, the Vogel number, was computed for large samples of Devonian to Cretaceous ammonites with a new method based on the ADA-model. The estimated ratios range from 2.4 to 3.4. The highest values are exhibited by uncoiled serpenticone ammonites, lowering in the sequence serpenticone-oxycone-spherocone. It is shown that the area-to-volume relationships are controlled by the involution (degree of overlapping) and the relative width of whorl section. The typical evolutionary trends serpenticone-spherocone and/or serpenticone-oxycone, broadly documented through the history of the Ammonoidea, could have been driven, at least in part, by the lowering of the area-to-volume ratio.