Editing Bog body (section)

== Bog chemistry ==
The preservation of bog bodies in peat bogs is a natural phenomenon and not the result of human mummification processes.<ref name="Fischer 237" /> It is caused by the unique physical and biochemical composition of the bogs.<ref name="Fischer 238">[[#Fis98|Fischer 1998]]. p. 238.</ref> 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.<ref name="Fischer 238" />

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.<ref>{{Cite book |last=Dente |first=Jenny |title=Bog Bodies: Reluctant Time Travelers |publisher=University of Texas |year=2005 |location=El Paso}}</ref> 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]].<ref name="lib">Silkeborg Museum {{Cite web |title=The Tollund Man – Preservation in the bog |url=http://www.tollundman.dk/bevaring-i-mosen.asp |url-status=dead |archive-url=https://web.archive.org/web/20170420154006/http://www.tollundman.dk/bevaring-i-mosen.asp |archive-date=20 April 2017 |access-date=20 August 2008 |website=Silkeborg Museum and Amtscentret for Undervisning, Aarhus Amt, 2004 |lang=da }}</ref> 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 level]]s similar to vinegar, preserve human bodies in the same way as fruit is preserved by [[pickling]].<ref name="lib"/> In addition, peat bogs form in areas lacking drainage and hence are characterized by almost completely [[Hypoxia (environmental)|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{{snd}}i.e., less than {{convert|4|C}}.<ref name="lib"/> 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&nbsp;°C.<ref name="lib"/>

The bog chemical environment involves a completely saturated acidic environment, where considerable concentrations of organic acids, which contribute most to the low pH of bog waters, and aldehydes are present.<ref>{{Cite thesis |last=Urban |first=N. R. |date=1 January 1987 |title=Nature and origins of acidity in bogs |url=https://www.osti.gov/biblio/5875514 |type=PhD |url-status=live |language=en |osti=5875514 |archive-url=https://web.archive.org/web/20210311001651/https://www.osti.gov/biblio/5875514 |archive-date=11 March 2021 |access-date=4 December 2020}}</ref> Layers of sphagnum, which are compacted layers of irregular mosses and other peat debris, and peat assist in preserving the cadavers by enveloping the tissue in a cold immobilizing matrix, impeding water circulation and any oxygenation.<ref>{{Cite web |title=Definition of SPHAGNUM |url=https://www.merriam-webster.com/dictionary/sphagnum |url-status=live |archive-url=https://web.archive.org/web/20210311001043/https://www.merriam-webster.com/dictionary/sphagnum |archive-date=11 March 2021 |access-date=4 December 2020 |website=www.merriam-webster.com |language=en}}</ref> An additional feature of anaerobic preservation by acidic bogs is the ability to conserve hair, clothing and leather items. Modern experimenters have been able to mimic bog conditions in the laboratory and successfully demonstrated the preservation process, albeit over shorter time frames than the 2,500&nbsp;years that Haraldskær Woman's body has survived. Most of the bog bodies discovered showed some aspects of decay or else were not properly conserved. When such specimens are exposed to the normal atmosphere, they may begin to decompose rapidly. As a result, many specimens have been effectively destroyed. As of 1979, the number of specimens that have been preserved following discovery was 53.<ref>Gill-Frerking, Heather. "Bog Bodies-Preserved from Peat." Mummies of the World. Ed. Wilfried Rosendal and Alfried Wiczorec. 2009. 63. Print.</ref><ref>Hajo Hayen: Die Moorleiche aus Husbäke 1931. In: Archäologische Mitteilungen aus Nordwestdeutschland. 2, 1979, {{ISSN|0170-5776}}, S. 48–55.</ref>

[[Image:Röst Girl.jpg|thumb|upright|Discoveries such as [[List of bog bodies#Germany|Röst Girl]] no longer exist, having been destroyed during the [[World War II|Second World War]] (photo date: 1926).]]