Why do bog bodies preserve so well?
Okie dok, so they survive because of three main factors: the acidity of the bog, it’s lack of oxygen and and chilled temperatures.
Acid: Not all bogs are acidic enough to maintain the integrity of the human figures. Bogs that are located in ares of low temperature and near bodies of salt water tend to support the continuous cycle of peat (or decaying vegetation) better than bogs that are not. As the life cycle of peat is carried out, plants arising, growing and then dying , the dying and dead plants release a kind of acid (humic I think). This acidity, coupled with the aerobic (no oxygen) conditions prevent the growth of many microscopic organisms. Bog bodies that preserve are thought to have been buried while water temperatures are cold so that the acids can act on the body prior to decay and prevent bacteria from colonizing the body fast enough to break it down. Acidic conditions are also the reason there are never any bones well preserved found , acid dissolves the calcium our bones are made from.
Oxygen: Lack of oxygen is responsible for preserving things like animal skin clothing, hair and nails. Again, lack of oxygen creates a closed system that prevents bacteria from being able to break down the bodies they way they regularly would.