PRESERVATION, MODES OF

The most important component in the preservation of biological remains is the presence of saprophytic organisms which feed on organics. Saprophytes thrive in alkaline, aerobic, humid environments; therefore, biological remains tend not to preserve in these same environments. They cannot survive in acidic, anaerobic, dry, cold environments; therefore, biological remains tend to preserve in these environments. Other factors which influence biological preservation are durability of materials and whether they can withstand mechanical and weathering destruction, as well as whether material has been carbonized or calcined, both of which increase their durability in all environments, particularly ones in which saprophytic organisms are present. Understanding preservation factors influencing biological remains can be straightforward, as in the relationship between the presence of saprophytic organisms and lack of biological remains; but is more likely to be complex, as presented here with the more disparate factors influencing biological preservation in areas such as Maine and the southwestern United States. The biological, environmental, and cultural factors influencing each region and assemblage need to be understood before factors influencing biological preservation can be elucidated.