A bog body is a human cadaver that has been naturally mummified in a peat bog. Such bodies, sometimes known as bog people, are both geographically and chronologically widespread, having been dated to between 8000 BCE and the Second World War. The unifying factor of the bog bodies is that they have been found in peat and are partially preserved; however, the actual levels of preservation vary widely from perfectly preserved to mere skeletons.
Unlike most ancient human remains, bog bodies often retain their skin and internal organs due to the unusual conditions of the surrounding area. Combined, highly acidic water, low temperature, and a lack of oxygen preserve but severely tan their skin. While the skin is well-preserved, the bones are generally not, due to the dissolution of the calcium phosphate of bone by the peat's acidity. The acidic conditions of these bogs allow for the preservation of materials such as skin, hair, nails, wool and leather which all contain the protein keratin.
See AlsoShanquella Robinson: Woman was alive when medics arrived, report saysI Want That Old Thing Back (S5:E17) by Mr. Z & 5thThe oldest known bog body is the skeleton of Koelbjerg Man from Denmark, who has been dated to 8000 BCE, during the Mesolithic period. The oldest fleshed bog body is that of Cashel Man, who dates to 2000 BCE during the Bronze Age. The overwhelming majority of bog bodies – including examples such as Tollund Man, Grauballe Man and Lindow Man – date to the Iron Age and have been found in northwest Europe, particularly Denmark, Germany, the Netherlands, United Kingdom, Sweden, Poland, and Ireland. Such Iron Age bog bodies typically show a number of similarities, such as violent deaths and a lack of clothing, which has led archaeologists to believe that they were killed and deposited in the bogs as a part of a widespread cultural tradition of human sacrifice or executed as criminals. Bogs could have indeed been seen as liminal places positively connected to another world, which might welcome contaminating items otherwise dangerous to the living. More recent theories postulate that bog people were perceived as social outcasts or "witches", as legal hostages killed in anger over broken treaty arrangements, or as victims of an unusual death eventually buried in bogs according to traditional customs.
The German scientist Alfred Dieck published a catalog of more than 1,850 bog bodies that he had counted between 1939 and 1986, but most were unverified by documents or archaeological finds; and a 2002 analysis of Dieck's work by German archaeologists concluded that much of his work was unreliable. Countering Dieck's findings of more than 1400 bog body discoveries, it seems that after a more recent study the number of bog body finds is closer to 122. The most recent bog bodies are those of soldiers killed in the wetlands of the Soviet Union during the Second World War.
Bog chemistry
The preservation of bog bodies in peat bogs is a natural phenomenon, and not the result of human mummification processes. It is caused by the unique physical and biochemical composition of the bogs. Different types of bogs can affect the mummification process differently: raised bogs best preserve the corpses, whereas fens and transitional bogs tend to preserve harder tissues such as the skeleton rather than the soft tissue.
A limited number of bogs have the correct conditions for preservation of mammalian tissue. Most of these are located in colder climates near bodies of salt water. For example, in the area of Denmark where the Haraldskær Woman was recovered, salty air from the North Sea blows across the Jutland wetlands and provides an ideal environment for the growth of peat. As new peat replaces the old peat, the older material underneath rots and releases humic acid, also known as bog acid. The bog acids, with pH levels similar to vinegar, preserve human bodies in the same way as fruit is preserved by pickling. In addition, peat bogs form in areas lacking drainage and hence are characterized by almost completely anaerobic conditions. This environment, highly acidic and devoid of oxygen, denies the prevalent subsurface aerobic organisms any opportunity to initiate decomposition. Researchers discovered that preservation also requires that the body is placed in the bog during the winter or early spring when the water temperature is cold – i.e., less than 4 °C (39 °F). This allows bog acids to saturate the tissues before decay can begin. Bacteria are unable to grow rapidly enough for decomposition at temperatures under 4 °C.
