Uncovering the holes and cracks: from anecdote to testable hypotheses in predation studies

Abstract

Biological interactions between organisms have long been believed to be very important in structuring communities and, when scaled up over geological time, in the evolution of organisms. Investigations of palaeontological evidence for predator–prey interactions have been popular pursuits, and a number of attractive hypotheses have been proposed which link increased predation pressure with a wide range of morphological and ecological changes which are apparent over the course of the Phanerozoic. In particular studies of fossil drill holes and repair scars in shelly prey have been common targets for research. However, the nature of some of our data has been rather anecdotal and restricted in range. Perhaps we should be more concerned that we are not picking up the true range of natural variability. This paper aims to highlight the sources of variability in our data and, going forward, to urge the collection of quantitative data from many more samples and (palaeo)environmental settings in order that we might properly be able to separate the intrinsic natural variability in our data from robust temporal or spatial trends.

The post‐Palaeozoic fossil record of drilling predation on lingulide brachiopods

“…The potential bias due to removal of shells by durophagous predators (Vermeij ; Harper et al . ; Harper ) is not possible to resolve.…”

“…However, taphonomic studies suggest that lingulids are unlikely to survive substantial transport (Emig 1986) and should be therefore less prone to this bias relative to molluscs. The potential bias due to removal of shells by durophagous predators (Vermeij 1989;Harper et al 1998;Harper 2016) is not possible to resolve. The identification of a drilling predator from its traces is difficult and controversial (Kowalewski 2002).…”

Ocean acidification and molluscan shell taphonomy: Can elevated seawater pCO2 influence taphonomy in a naticid predator–prey system?

“…Drilling predators are known to prey on a suite of taxa with varying shell morphometries (both presently and in the geologic past)-some of which may be more prone to dissolution/breakage than others, including bivalves and gastropods, brachiopods, tube-dwelling polychaetes, scaphopods, ostracods, decapods, chitons, and barnacles, among others (e.g. Kelley and Hansen, 2003;Hoffmeister et al, 2004;Morton and Harper, 2009;Klompmaker, 2012;Martinell et al, 2012;Harper, 2016;Klompmaker et al, 2015). Furthermore, while the presence of drill holes in molluscan prey may not result in the preferential fragmentation of drilled shells (Zuschin and Stanton, 2001;Kelley, 2008;Chojnacki and Leighton, 2013), high rates of breakage across drill holes in other taxa such as tube-dwelling polychaetes suggest that drill holes could result in preferential breakage for other species (Klompmaker, 2012).…”

Quantitative Analysis of Repaired and Unrepaired Damage to Trilobites From the Cambrian (Stage 4, Drumian) Iberian Chains, Ne Spain

“…Examining repaired injuries and drillholes on exoskeletons at various locations and in different formations is important for understanding the variability of predation pressure across space and time (Harper 2016). Such data can also be used to identify stereotypy of predators targeting specific locations on prey exoskeletons or specific prey sizes (e.g., Conway Morris and Bengtson 1994;Leighton 2001Leighton , 2011Robson and Pratt 2007).…”