August 05, 2018

Site-selectivity in naticid drilling predation

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Naticids are a group of predators in soft-bottom marine communities. They drill a hole through the wall of the prey’s shell in order to feed. Laboratory-feeding trials, beach and museum samples were used to evaluate site-selectivity in the behavior of Notocochlis unifasciata on the bivalves Protothaca  asperrima and Iliochione subrugosa. Despite that death assemblages could mix records from multiple predators, the distribution of predatory traces on samples of I. subrugosa is reminiscent of the pattern observed on the feeding trials. Currently, I’m developing a spatially explicit approach to study site-selectivity using point process modeling that may improve our ability to identify drilling predators in the fossil record and to explore more rigorously spatial and temporal changes in site selectivity by drilling predators.

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August 08, 2018

The post-Palaeozoic fossil record of drilling predation on lingulides 

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Drilling predation on shelled marine invertebrates represents a unique opportunity to quantifying a biological interaction in the fossil record. Predatory drillholes provide information on intensity and selectivity of this predator-prey interaction. Based on an extensive compilation of literature sources and museum samples, the macroevolutionary history of the drilling predation on the lingulide brachiopods was assessed.  Several examples of this biological interaction, ranging from Eocene to Recent in age, were documented. The Mesozoic-to-Cenozoic increase in drilling frequencies on lingulides is similar to the trends observed in other marine benthic invertebrates and consistent with the hypothesis that predation pressures increased through time in marine ecosystems

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