Bog bodies, also known as bog people, are preserved human bodies found in sphagnum bogs in Northern Europe, Great Britain and Ireland. Unlike most ancient human remains, bog bodies have retained their skin and internal organs due to the unusual conditions of preservation. Under certain conditions, the acidity of the water, the cold temperature and the lack of oxygen combine to tan the body's skin: skeletal preservation is very rare in these bodies, as the acid in the peat dissolves the calcium phosphate of bone. The bodies provide very useful research material for archaeologists. Some of the bodies retain intricate details like tattoos and fingerprints. Fingerprint expert C.H. Vogelius Andersen was astonished to find that Grauballe Man's hand prints were clearer than his own. The stubble and facial features of Tollund Man are particularly well preserved.

Bog chemistry

There are a limited number of bogs which have the correct conditions for preservation of mammalian tissue. Most of these are located in the colder climes of northern Europe near bodies of salt water., For example, in the area of Denmark where the Haraldskær Woman was recovered, salt 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, conserve the 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 conservation also required the body be placed in the bog during the winter or early spring when the water temperature is cold -- i.e., less than 4 °C (40 °F). This allows the bog acids to saturate the tissues before decay can begin. Bacteria are unable to grow rapidly enough for decomposition at temperatures under 4 °C.

The bog chemistry environment involves a completely saturated acidic environment, where considerable concentrations of organic acids and aldehydes are present. Layers of sphagnum and peat assist in preserving the cadavers by enveloping the tissue in a cool immobilizing matrix, impeding water circulation and any oxygenation. An additional feature of anaerobic preservation by acidic bogs is the ability to conserve hair, clothing and leather items. The Bronze Age Egtved Girl, also discovered in Jutland, Denmark is a good example. Modern experimenters have been able to mimic bog conditions in the laboratory and successfully demonstrate the preservation process, albeit over shorter time frames than the 2,500 years the Haraldskær Woman's body has survived. Most of the bog bodies discovered had some aspects of decay or else were not properly conserved. When such specimens are exposed to the normal atmosphere they may rapidly begin to decompose. As a result, many specimens have been effectively destroyed.

Bog bodies found

More than a thousand bog bodies have been found in regions associated with the Celts of the Iron Age. The earliest bog body, that of Koelbjerg Woman, has been radiometrically dated to be about 5500 years old. The newest is of the 16th century AD, a woman in Ireland who may have been buried in unhallowed ground following a suicide. By far the majority of the bog bodies belong to the Celtic Iron Age, some as late as the 4th century BC.

Preserved bodies of humans and animals have been discovered in bogs in Britain, Ireland, northern Germany, the Netherlands, Denmark (both Jutland and Zealand), and southern Sweden. Records of such finds go back as far as the 18th century. The first bog body to be discovered was that of Kibbelgaarn body in the Netherlands, in 1791. It is not readily apparent at the time of discovery whether a body has been buried in a bog for years, decades, or centuries. However, during the 20th century, forensic and medical technologies (such as radiocarbon dating) were developed that allow researchers to more closely determine the age of the burial, the person's age at death, and other details. Scientists have been able to study their skin, reconstruct their appearance and even determine what their last meal was from their stomach contents. Their teeth also indicate their age at death and what type of food they ate throughout their life time.

Causes of death

Many bog bodies show signs of being killed, stabbed, bludgeoned, hanged and strangled, or a combination of these methods. The nipples of Old Croghan Man were sliced almost through. The corpses were sometimes decapitated, then deliberately buried in the bog, staked down with stakes or twisted willow or hazel withies. Interpretations of the forensic examinations vary; it is debated whether they were ritually slain and placed in the bog as an execution for a crime, or as a human sacrifice. Some bog bodies, such as Tollund Man from Denmark, have been found with the rope used to strangle them still around their necks. Some, such as the Yde Girl in the Netherlands and bog bodies in Ireland, had the hair on one side of their heads closely cropped, although this could be due to the one side of their head being exposed to oxygen for a longer period of time than the other. The bog bodies seem consistently to have been members of the upper class: their fingernails are manicured and tests on hair protein routinely record good nutrition. Strabo records that the Celts practiced auguries on the entrails of human victims: on some bog bodies, such as one of the Weerdinge Men found in southern Netherlands, the entrails have been partly drawn out through incisions.

However, in light of a recent National Geographic article, it may be possible that these injuries were not always inflicted by other people as a means of torture, but rather the weight of the bog. This would explain instances of smashed bones and the like.

The unity of the details of violent ritual slaughter over such a wide swathe of Northern Europe is a testament to a broadly unified culture, one which corroborates the breadth of material culture found in Celtic Iron Age archaeological sites of the La Tène type.

Archaeological research

In the case of the "mummies" of Cladh Hallan the burials have been interpreted as a primitive method of embalming important individuals.

X-ray is a very important step in uncovering the bog bodies as it can draw a picture of a body in the peat, which can then be removed without harming it by cutting blindly. Radio carbon dating is also very common as it accurately gives the date of the find, most usually from the Stone Age. In terms of determining the cause of death of the bodies, in a surprising number of cases there are obvious signs of violence and murder. The Tollund Man, for example, had a rope knotted round his neck and Windeby I had been staked down under the water.

Because the peat marsh preserves soft internal tissue, the stomach contents can be analyzed. These give a good picture of the diet of those people. Facial reconstruction is one particularly impressive technique used in studying the bog bodies. Originally designed for identifying modern faces in crimes, this technique is a way of working out the facial features of a person by the shape of their skull. The face of one bog body, Yde Girl, was reconstructed in 1993 by professor Richard Neave of Manchester University using CT scans of her head. Yde Girl and her modern reconstruction are displayed at the Drents Museum in Assen. Such reconstructions have also been made of the heads of Lindow Man (British Museum, London, United Kingdom), and Windeby Girl (Archäologisches Landesmuseum, Schleswig, Germany).

Notable bog bodies

(Dates given are radiocarbon dates.)

• Clonycavan Man
• Grauballe Man, found 1952 in Nebelgård Mose, a bog in Jutland, Denmark.
• Haraldskær Woman, 5th century BC, found 1835 in a peat bog in Jutland, Denmark
• Lindow Man
• Old Croghan Man
• Tollund Man, 3rd – 2nd century BC
• The mummies of Cladh Hallan, Scotland 1600 B.C.-1300 B.C.
• Yde Girl, 170 BC – AD 230.
• Bocksten Man

See also

• Bog butter
• Mummy
• Natural mummification
• Incorruptibility

References

• PBS/ NOVA, "The Perfect Corpse"
• Peter Vilhelm Glob, The Bog People: Iron-Age Man Preserved. (Cornell University Press, 1969; reprinted 2004.
• Archaeological Institute of America, 1997. Archaeology: "Bodies of the Bogs"
• van der Sanden, Wijnand, 1996. Through Nature to Eternity: The Bog People of Northwest Europe (Museum Boymans van Beuningen) Accompaniment to his exhibition at Silkeborg, Denmark.
• Don Brothwell, 1987. The Bog Man and the Archaeology of People (Harvard University Press) Original publisher, British Museums Publications, Ltd., London (1986) ISBN 0-7141-1384-0
• Tim Taylor, 2003. Buried Soul (Fourth Estate Ltd)
• Miranda Aldhouse Green, 2002. Dying for the Gods (Tempus Publishing)
• Wijnand van der Sanden, 1996. Through Nature to Eternity (Batavian Lion Int.)