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PALEONTOLOGICAL SOCIETY PAPERS, V. 8, 2002one needs to make an explicit claim as to why oneof them is selected for the analysis).5. Various protocols and analytical methods canbe fruitful depending on the logistic circumstancesand scientific goals of a paleoecological project.6. The most fruitful analyses are based onrelative comparative approaches. Latitudinalchanges in predation intensity or temporal shifts inbehavioral stereotypy are more insightful than a givenabsolute frequency of predation or a specific degreeof stereotypy. Comparative analyses can also helpavoid various biases. For example, taphonomic biasor spatial/environmental overprint can be minimizedif comparisons are done for samples from similartaphonomic settings and comparable depositionalenvironments (the “isotaphonomic approach” ofBehrensmeyer and Hook, 1992).7. Finally, regardless of the above points, itseems particularly useful to provide raw data (eitheras repository data or appendices) so that futureresearchers can re-analyze these data in new ways.Consider all the data on predation traces that havebeen collected over the last 40 years and cannot beaccessed. At best, a few succinct tables and graphsare all that remain. This is the one mistake we neednot repeat in our future efforts.CLOSING REMARKSThe methodological dimension of research onpredation traces is a rapidly growing field of study.Based on current activities, the futuremethodological themes that are likely to benefitour discipline include (1) laboratory experimentsthat should help us in dealing with varioustaphonomic biases, (2) neontological analyses thatprovide reference baselines and should further helpus to understand various confounding factors thatneed to be accounted for before proposing anyinterpretation (e.g., spatial gradients in predation),and (3) numerical modeling that should continueto improve our arsenal of statistical tools andanalytical strategies.Despite all caveats and problems, distincttraces of predation such as drill holes offer one ofthe best sources of quantitative data inpaleoecology. Such traces provide unusuallyfavorable research conditions for testing newmethodologies and for pushing our interpretivepowers to the highest possible limits. Research onpredation traces can thus be viewed as one of theforemost areas for testing the scientific limits ofour discipline—by examining traces of predationwe can examine the limits, strengths, methods, andassumptions of paleoecology.ACKNOWLEDGMENTSThis project was supported by the NSF grantEAR-9909225. I thank Richard Alexander, GregDietl, Thor Hansen, Alan Hoffmeister, PatriciaKelley, and Lindsey Leighton for numerouscomments and suggestions that improved thismanuscript considerably.REFERENCESALEXANDER, R. R. 1981. Predation scars preserved in Chesterian brachiopods: probable culprits and evolutionaryconsequences for the articulates. Journal of Paleontology, 55:192–203.ALEXANDER, R. R. 1986a. Resistance to repair of shell breakage induced by durophages in Late Ordovicianbrachiopods. Journal of Paleontology, 60:273–285.ALEXANDER, R. R. 1986b. Frequency of sublethal shell-breakage in articulate brachiopod assemblages throughgeologic time. In P. R. Racheboeuf and C. C. Emig (eds.), Les Brachiopodes Fossiles et Actuels, FirstInternational Brachiopod Congress Proceedings, Biostratigraphie du Paleozoique, 4:159–166.ALEXANDER, R. R., AND G. P. DIETL. 2001. Shell repair frequencies in New Jersey bivalves: a recent baseline fortests of escalation with Tertiary, Mid-Atlantic congeners. Palaios, 16:354–371.30