Gastropod predation on corbulid bivalves: palaeoecology or taphonomy?

A case study on corbulid bivalves is presented, illustrating the complexity of bias and related problems, when attempting an objective analysis of gastropod drill-hole data. Phenomena, previously mentioned in literature, are re-examined and additional data are given on unsuccessful attacks. Acceptable palaeoecological explanations are suggested for the results obtained : the occurrence of corbulids in large monospecific clusters may cause some of the phenomena. Further research on this is needed. On the other hand, taphonomical bias seems to be another important parameter, making it impossible to reach firm conclusions. Therefore, the impact of taphonomy needs further investigation, before palaeoecological value can be given to data on gastropod drill-holes