The Temporal Resolution of Epibiont Assemblages: Are They Ecological Snapshots or Overexposures?

Abstract

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Encrustation patterns on Late Cretaceous (Turonian) echinoids from southern Poland

“…Rodland et al 2006) may be excluded in our case because encrustation of test oral surfaces and periprocts, as well as lack of stereom malformations, shows that the echinoids were dead.…”

“…Additionally, disturbance of the substrate and removal of epibionts from the host have also been taken into account (e.g., Wilson 1985Wilson , 1987Rodland et al 2006). In the case of the Polish Turonian echinoids, a scenario of low productivity is probable.…”

“…Erasure of epibionts produces a taphonomic artifact (see e.g., Rodland et al 2006), masking the true intensity of encrustation and abundance of encrusters. However, the ''cleaned'' substrate may be later re-encrusted.…”

“…It is predicted that substrates exposed for longer on the sea floor, including redeposited substrates, will have a greater chance to be colonized/ recolonized or more heavily encrusted (e.g., Reolid et al 2005;Rodland et al 2006). Also substrate size may be significant for exposure time, with larger substrates being exposed for longer.…”

“…Redeposition episodes that might have increased the chances of previously non-encrusted echinoids to become re-exposed for colonization are unknown. However, Rodland et al (2006), based on dated subfossil brachiopods, proved that time of exposure does not matter. Additionally, actualistic data suggest that within a few days the preservable taxa can settle.…”