REPAIR SCARS 101: THE INFLUENCE OF DATA STANDARDIZATION ON THE FREQUENCY OF UNSUCCESSFUL SHELL-CRUSHING PREDATION

The use of unsuccessful traces of shell-crushing predation preserved as repair scars on the shells of mollusks is increasingly common in both ecological and paleontological studies. We examined the effects of different types of data standardization (e.g., body size, shape, and exposure time to enemies) on the calculation of repair frequency for a hypothetical dataset of 1,000 specimens of a marine gastropod species that varies across its geographic range in morphology and life history. We based assumptions for our system on literature reports of living marine gastropod species. Results highlight the importance of data standardization; depending on the level of standardization, differences in estimated repair frequency varied widely. The use and continued development of standardization methods should both enhance our ability to detect ecologically meaningful signals, and facilitate unbiased tests of hypotheses concerned with the importance of shell-crushing predators in ecology and evolution.