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BAMBACH—SUPPORTING PREDATORSFIGURE 4—Maximum, minimum, and mean boundary-crossing diversity estimates for predatoryanthozoans through the Phanerozoic.diversity for predatory anthozoans (and if a higherproportion of tabulates and rugosans were predatorythan for scleractinians, it could even be lower); and3) diversity of predatory anthozoans in the Cenozoicis not markedly greater than in the Late Jurassic orCretaceous, a different pattern from the diversitytrend for either Metazoa or predators overall.The reason the range of estimated diversity ofpredators is shown for the anthozoa (Fig. 4) isbecause the uncertainty of recognizing predators ismaximal for this group. Also, because there iscomplete replacement in the corals at the order levelbetween the Paleozoic (Rugosa and Tabulata) andMesozoic-Cenozoic (Scleractinia), it is possible thatthe proportion of predatory coralline anthozoa (thevast majority of the genera recorded in the fossilrecord) was markedly different in the Paleozoicversus the Mesozoic-Cenozoic. In fact, the apparentevolution of hermatypy in the scleractinia makesthis a case in which a decrease in proportion ofpredator taxa between the Paleozoic and Mesozoic-Cenozoic, rather than an increase, is likely.Polychaetes.—Polychaetes are soft-bodied andhave a poor fossil record. Scolecodonts (phosphatictooth-like structures) are known and have beendescribed, but lägerstetten with soft-partpreservation are also an important source of dataon these infrequently fossilized organisms.Figure5 displays the diversity data known forpredatory (not suspension-feeding) polychaetes.The very stable form of the boundary-crossing(continuing) diversity plus the widely spaced sharpturnover peaks indicates that much of the data are“range-through” from widely spaced occurrences,apparently from lägerstetten. A very strikingfeature, however, is that the maximum diversitypeaks, which are widely spaced and primarilyrepresent “monographic effects” from lägerstetten,form a near-parallel diversity path if the points areconnected (see the dashed line in Fig. 5). It appearsthat the diversity signal is stronger than the biasesof the record and can show through even in a poor327