When the Ac/Al ratios are considered, degradation by biological activity becomes an additional factor to be considered. The edge of the Mary Rose, with low S/G and high Ac/Al ratios, is potentially consistent with fungal degradation. Meanwhile, the Mary Rose core sample shows a very low S/G ratio coupled with low Ac/Al ratios, which suggests bacterial degradation has occurred. The Mary Rose wood is known to be associated with bacterial communities . Studies using different analytical techniques (py-GCMS, py(HMDS)-GCMS, classical wet chemistry analysis) suggest that S/G ratios may also be lower in heartwood samples compared to sapwood samples due to fundamental differences in the cell structure of the living tree as it ages . These three factors: burial, low initial values, and bacterial degradation, may have combined to produce the uniquely low S/G and Ac/Al ratios in the Mary Rose core sample.