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"Who controls the past controls the future. Who controls the present controls the past." --George Orwell, 1949

Human bones. They just lie there in the ground, slowly degrading to the atoms from which they were originally created, often the only lonely reminder of a past life. A part of a person who thought, lived, possibly procreated, and performed many other actions that we do in our daily lives. The bones, however, are silent. Is there any information that can be garnered from bone? Even some archaeologists question the value of disturbing human remains. This rebellious group of archaeologists is slowly becoming a minority. With advances in molecular biology, statistics, and skeletal biology, the information that can be found on a fleshless human bone can indeed tell great tales.

How does one go about finding human remains? One could start with the local municipal cemetery, but this more than likely will attract the attention of the local constabulary. Archaeologists often seek bones in areas that really leave no tell-tale sign on the surface, at least to the untrained eye. Bones are frequently found near human habitations. There is a simple explanation for this; what makes a site attractive to modern society probably had a similar attraction to past societies as well.

Sometimes, the human remains are found by accident. During a construction project or the plowing of a farmer's field, artifacts are turned up. When this happens, a trained archaeologist should be, and in some jurisdictions, must be consulted to survey the site prior to the work continuing.

Infrared photography, aerial photography, and even some electrical detection methods can determine the location of past human populations. Though the electrical methods are unreliable, these methods were used, ironically, to find one of the oldest human skeletons ever found.

Preparing To Dig

Prior to the beginning of a dig for human remains, the archaeologist must seek permission of different individuals and agencies. This will save the researcher a lot of legal grief in the long run. Many cultures do not sanction the destruction of their burial grounds and destruction of a site is exactly what an archaeological excavation will do. Cooperation with landowners is essential.

Once cooperation is attained, the dig still should not begin. An excavation is a lot like a construction project. Almost half of the work is done before even a single shovel is put in the ground. Local historical data should be looked at to help determine the layout of the excavation. Some cultures buried their dead in circles, and others buried them according to age; the list of options available are as plentiful as the human cultures past and present. If previous history is available for a site, it can be used to plan the excavation and how it should proceed.

It is also important to determine the extent of the site. This is done by digging test trenches. Once the size of the site is determined, the site is recorded. Archaeologists begin by either superimposing a grid on the site and locating the burials on the grid or by using a transit to map each feature of a site exactly. The choice of methodologies used varies with the size of the site. A large site is usually better served by a transit.

The Dig Itself

Now the archaeologist is ready to start getting his or her hands dirty; most of the work is done by cheap labor (often provided by grad students). The soil is first removed around each bone. If the skeleton is complete and not a jumble of bones, it is called a primary burial. A secondary burial is a collection of non-articulated human bones. This, in itself, can be very revealing as it can show a complex treatment of the body. The location and relationships amongst the jumble of bones may reveal the manner and sequence of deposition, and may even provide insight into the mortuary practise of the culture.

Once the bone is exposed from the soil, a black and white photograph and color photograph are taken to provide a visual record of the overall position and arrangement of the bone(s). Field notes are not always complete and a photograph can often make up for this shortfall. The old saying, "A picture is worth a thousand words," has a great deal of meaning for an archaeological dig.

Field notes should include the location of the body within the pit. This 'location' refers to the position of the three anatomies (legs, arms, and head) within the pit and is not in relation to other points. The notes also include the orientation of the body, if there is a bone articulation. Is the body buried on its back, side, front or even in a seated posture? The depth of the bone in the pit is also recorded as the distance between the surface and the highest and lowest part of the bone. Measurements of the distance between the edge of the pit and other artifacts within the excavation pit are also recorded.

These exhaustive measurements are taken for an exhaustive description. Every time that an archaeological site is dug up, it is effectively destroyed for future archaeologists to study. In fact, in many archaeological digs, a random selection of sites is taken so that the entire site does not necessarily have to be dug up; future researchers will still have an opportunity to put their shovel to the soil. Therefore, the exhaustive description allows future researchers -- armed with new archaeological techniques -- to draw further conclusions based on those earlier descriptions. It also allows present archaeologists to perform a peer assessment of the conclusions (essential in today's scientific endeavours) of the archaeologist.

The pathological condition of the bones is extremely important to record, since the removal of bones from the soil can often destroy the subtle bone changes caused by disease; those data would then be lost forever. If there is perishable material in a excavation pit such as clothing, hair, leather or any other materials, information on this material is also recorded.

Soil samples of the excavation pit are also taken. These give the archaeologist information on why the bones were preserved and why they are discolored. They can also offer clues as to why a bone may be deformed (without the soil sample, a deformation may be treated as a pathology). Soil samples can also reveal pollen grains and insect parts which can give clues as to when in the calendar year the body was buried and even if the body was buried where it died.

As today, past cultures did cremate bodies. Unfortunately, many of the remains will be small and unworthy of preservation; however, the site can still be recorded. It is also important to remember that burning can alter the shapes of bones, making interpretations of the site difficult. However, a careful survey can always overcome this potential problem.

Contrary to what might be expected, preservatives are not usually used on bones. Rather, they are removed from the soil as quickly as possible after exposure. The elements are not very kind to bone, and preservatives can alter potential microbiological information in a bone. If a skeleton is to be removed intact, as may be done for a museum display, the body is enclosed in a jacket made up of wet cloth covered by plaster. A trench is dug around the cast and the skeleton is removed intact from the pit.

What We Can Learn From Bones

Now that the bones are collected, what can they tell us? The simple answer is, "a lot." For example, bones can tell the researcher the sex of the body. Determining the sex of adults is the easiest; it's more difficult with subadults, and with infants it's almost impossible. To determine the sex of subadults, there is a roundabout method: the researcher looks at the calcification of the teeth. Calcification occurs at the same rate in males and females. Then the researcher will independently look at the postcranial skeleton; this part grows more quickly in females. For each parameter, the researcher will determine the age of the body. If the age estimate of teeth is about the same as that of the postcranial skeleton, the body is that of a male. If the estimates do not agree, the body is that of a female.

Determining the sex of adult skeletal material is a lot easier. The best group of bones for this is the pelvic bones. Since the pelvis is the location of the birth canal, there are some very specific differences in this region of the anatomy between males and females. In fact, there is a 90% accuracy in determining the sex of skeletal material based on the pelvic bones. The skull of an adult is somewhat more problematic when it comes to sexing, but in general, the male skull will be more robust than that of a female. The same holds true for the long bones such as the femur or tibia.

Stature can also be determined if long bones are found, either arms or legs. Using data from known skeletal populations, researchers have come up with a number of regression analysis equations that estimate the stature of the living person who was once in possession of a particular long bone. Race can be determined with some success. The face of a person of African descent will usually display little or no protrusion of the cheek bones and have a wide nasal aperture. An Asian will often show more protrusion of the cheekbones and Caucasians usually have withdrawn cheekbones. The femur (thigh bone) is a good tool to classify the race of an individual. The femur of a person of African descent is often straight; that of an Asian is twisted in appearance; and in Caucasians, it falls somewhere in between.

Determining the age of a bone is easier than race classification (and more important if you want to get a good demographic picture of a past society). Each bone has its advantages and its drawbacks. The younger the bone in its development, the easier it is to determine its age, since dental eruption, fusion of bone ends to shafts, fusion of bony plates, and even the development of certain bones all occur within a small range of years. After the age of twenty, the aging is somewhat more problematic. The pubic symphysis, the joint at which the hip bones meet at the front of the body, is rough and furrowed in a younger person and smoothed over in an older person. The skull of a younger person is made up of clearly defined sections divided by lines of attachment called sutures. As the skull ages, the sutures become less defined and smoothed over. The skeleton, as a whole, will also show more degenerative changes, the older it gets.

Microbiological analysis of bone can also reveal a bone's age. It is hard to imagine that the bone that was lying lifeless in the dirt during an excavation was actually living tissue at one time, but bone is living and is constantly being created and destroyed. A healthy bone maintains a good balance between the two processes. When bone is first formed, the long bone cortex is made up of thin parallel layers called circumferential lamellar bone. As the bone ages, microscopic structures called osteoclasts cut longitudinal tunnels in the cortex, thus creating interruptions in the layers. If you cut a cross-section of the bone, the tunnels look like ovoid holes. The holes are filled in gradually by structures called osteoblasts, but a small opening remains in the centre. This opening is the Haversian canal and is essential to allow for the penetration of the bone by blood vessels and nerve fibres. The entire complex of the circle and the Haversian canal is known as the osteon. The outer limit of the canal is a denser layer of bone called a reversal line. It marks the boundary where the tunneling has ended. Osteon formation occurs throughout life and since spacing of the osteon is controlled, we know that the more numerous they become, the greater the amount of overlap. Based on the ages of known bone samples, scientists can use the osteon overlap as a guide to bone age.

Conclusion

There is a lot of information that can be garnered from an archaeological dig and especially from the human skeleton. Mystery fiction has recently come across this new avenue of storytelling. The novels of Aaron Elkins, Patricia Cornwell, and Kathleen Reichs have all consistently been on the bestseller lists. In all cases the hero or heroine is a forensic pathologist and, more specifically in the case of the novels of Reichs and Elkins, a forensic anthropologist (an archaeologist who specializes in skeletal biology).

Speculative fiction, however, has rarely been so kind to archaeology, unlike many of the other sciences. More often than not, a speculative fiction archaeological tale is nothing more than a swashbuckling tale of time travel, almost on par with many movies that depict archaeologists as their heroes. However, all is not lost. Several speculative fiction tales do deal with archaeology in a no-nonsense manner. In Ray Bradbury's The Martian Chronicles, there is an archaeological element in the exploration and the eventual colonization of Mars. Gregory Benford in Artifact describes the discovery of an alien artifact. Fantasy writers also have written successfully of archaeological digs. Anne McCaffery in her Pern series writes of the excavation of a site of the first settlers of Pern in All the Weyrs of Pern. She also collaborated with Mercedes Lackey in The Ship Who Searched, about an extraterrestrial dig in which the daughter of the excavators becomes ill. Robert Silverberg in his Lord Valentine series wrote of the excavation of the ancient city of the shapeshifters in Valentine Pontifax.

Unfortunately, speculative fiction writers do not often incorporate archaeology into their stories. Both fields would benefit if they did. Archaeology would benefit by a realistic profile that speculative fiction and, in particular, science fiction, can provide. Speculative fiction would be able to tap into a whole new territory. Who knows, you may be the first to extrapolate some new archaeological technique that will revolutionize the science. It would not be the first time that speculative fiction has foreseen a scientific revolution. Even if that is not the case, speculative fiction has the power to inspire future archaeologists just as it has some of the greats of physics, astronomy, and biology. A little farfetched? That's what speculative fiction is all about.

 

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Peter Jekel is the Director of Infectious Disease Prevention in one of the largest Health Department Districts in Ontario. He has lived in Bracebridge, Ontario with his family for the past 16 years. His previous publications in Strange Horizons can be found in our Archive.



Peter Jekel runs the Infectious Diseases Program for one of the largest Health Department Districts in Ontario, Canada. He lives with his family, made up of wife, daughter, dog, 3 cats, 20 fish, and a rabbit. His previous publications for Strange Horizons can be found in our Archive.
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