Demineralization Mechanism of 

 Boring Gastropods 



MELBOURNE R. CARRIKER, Systematics-Ecology Program, Marine 

 Biological Laboratory, Woods Hole, Massachusetts 



DAVID B. SCOTT. Laboratory of Histology and Pathology, National 

 Institute of Dental Research. Bethesda, IVIarjland 



GARLAND N. MARTIN, Jr.. Laboratory of Histology and Pathology, 

 National Institute of Dental Research. Bethesda. Maryland 



A WIDE range of species in at least eight invertebrate phyla and 

 three major plant groups have the capacity to excavate the calcare- 

 ous exoskeletons of other organisms. The nature of the mechanism 

 by means of which this is accomplished is little understood. It is 

 not known whether the mechanism is fundamentally similar in 

 predatory boring gastropods and octopods which penetrate bivalves 

 for food; in bivalves which excavate shelters in the valves of mol- 

 lusks; in sponges, flatworms, bryozoans, phoronids, pohchaetes, and 

 barnacles which excavate calcareous substrates for nutrients and/or 

 protection; in shell-boring fimgi, algae, and bacteria; and in micro- 

 organisms associated with human dental caries. Among plants and 

 lower invertebrates, penetration of calcareous substrates is probablv 

 achieved by chemical means alone; in higher invertebrates, by 

 mechanical or chemical means or a combination of these. Various 

 hypotheses suggest that release of COl', acids, enzymes, or sequester- 

 ing agents may bring about dissolution of shell. In higher inverte- 



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