NATICID CONFAMILIAL DRILLING PREDATION THROUGH TIME

Abstract

Gastropod drilling predation in the fossil record is prevalent and has been documented by many workers; however, vivid documentation of confamilial naticid predation is poor. Here, data compiled from previously published sources, supplemented by unpublished museum collections, document different aspects of naticid confamilial predation (NCP) in a temporal-latitudinal context. Confamilial drilling frequency (DF) showed a Cretaceous low, a small rise to a stable plateau in the Eocene, followed by a peak in the Oligocene, and finally a drop to a stable level from the Miocene to the Holocene. The stepwise rise in DF is comparable with the overall history of drilling predation. However, the temporal increase in DF was visible only in the mid-latitudes, while in other latitudes, no temporal trend was observed. The frequency of failed attack has always been very low. In comparison, a decrease in prey effectiveness (PE) was observed in the Neogene relative to the Cretaceous and Paleocene–Eocene intervals. In case of site selectivity, either apertural or abapertural sites were targeted until the Oligocene, and subsequently became more random. Some of these trends may be biased based on insufficient site selectivity data as well as uneven sampling from different latitudes representing different time intervals. More data on quantification of predation intensities along with the behavioral aspects of NCP are required to properly document other aspects of this interaction.