PHOSPHATIZATION OF SOFT-TISSUE IN EXPERIMENTS AND FOSSILS

Soft-tissues phosphatized in laboratory experiments closely resemble fossil phosphatized soft-tissues, indicating that similar processes were involved. The smaller the aggregations of calcium phosphate particles precipitated the greater the fidelity of morphological preservation. The highest fidelity occurs where the bacteria themselves are not replicated even though precipitation is bacterially induced. While extensive phosphatization of larger carcasses, however, may necessitate the build-up of concentrations in the sediment beforehand, this is not the case for phosphatization of small guantities of soft-tissue. Mineralization of soft-tissue in the laboratory is not 'instant' but mag take several weeks, or even months if decay is inhibited. The precipitation of associated calcium carbonate is controlled by shifts in pH in response to the decay process.