The Experimental Degradation of Archaeological Human Bone by Anaerobic Bacteria and the Implications for Recovery of Ancient DNA

DNA recovery from human bone has been key to the developing science and technology of ancient DNA studies. The recovery of macromolecules from bone however, does not correlate well with recognisable parameters of preservation and predicting DNA recovery rates from ancient bone can be very difficult. The extent of degradation of buried bones often depends on environmental taphonomy and can vary from virtually none to complete and rapid destruction. Although soil or related microbes are undoubtedly responsible for the majority of this structural degradation over time, exceptionally little is known of the mechanisms or specific bacteria involved. Fungi were previously thought to be responsible for destructive processes (tunnelling) within bone but over the last 30 years the role of bacteria has been increasingly recognised. Our aim was to develop a less complex in vitro model of the destructive effects of microbes on bone which might allow a better understanding of the recovery of mitochondrial or pathogen DNA over time.