|Click for photo credit.|
When I was working on my Ph.D. on human alterations of soils, my advisor, Dr. Robert Eidt, told me that I needed to take archaeology courses so that I would have a deeper understanding of the significance of humans in environmental change throughout time. He always made the point that humans have been altering the planet for millennia and that this change could be mapped and quantified chemically and physically in soils. I took as many archaeology
courses as I could. My experiences led me to work on a number of archaeological sites in Yemen, the Midwest, Florida, California, Arkansas, and Tennessee. Yet nothing demonstrated the direct impact of humans on soils as did work I completed with Dr. Lynne Goldstein on a cemetery excavation in California.
|The impact of humans on the environment is evident almost everywhere.|
Here you can see the classic elevated "tel" or pile of debris present
in ancient cities of the Old World. This is the ancient city of Marib
in Yemen near where I worked for two field seasons in the 1980's.
Click for photo credit.
Here, we found that the soils impacted preservation of graves and human remains and that the graves impacted soil development. The soils in the cemetery were so incredibly variable that in some cases full coffins were preserved while in other cases we would find only coffin nails. In some cases bone fragments would be present and in other cases only teeth could be found. The high variability of the natural soils due to the complex geological setting of coastal California led to variability in preservation. At the same time,
we saw significant soil changes as a result of the decomposition of the coffins and their contents. Hard metallo-organic soil pans formed in some places that were too dense for standard archaeological excavation techniques.
|The dietary choices we make are imprinted in our bones. What|
will archaeologists learn about our modern diet if they ever
did you up? Click for photo credit.
This specific example is but one way that the dead tell us about the environment.
Over the past few decades, scientists have been examining the remains of the ancient dead to find out what we can learn from them about past environments. We can tell, for instance, whether or not their diet consisted of certain types of foods. These foods tell us about the relationship of our ancestors with their environment. It has been found, for example, that Neanderthals ate mainly a meat diet based on the ratios of nitrogen-15 to nitrogen-14. Their bones tell us that their diet is more akin to that of wolves than almost any other creature.
|What we choose to bury with the dead|
can also tell us about the environment. What
common thing do you own that could tell us
about the our times? Click for photo credit.
Advances in skeletal bone chemistry allows researchers to reconstruct not only diet, but also environmental risks, such as proto-industrial lead exposure. By studying the chemistry of human remains we can also reconstruct environmental conditions such as climate, presence of particular ecosystems, and natural hazards.
The way graves are preserved also tells us about the environment from the time of burial to the present. Perhaps the most obvious example of this comes from our understanding of the ancient bog burials of Great Britain. Here, peat cutters have found the nearly intact remains of bodies that were sacrificed hundreds of years ago. We know that the environment in these situations remained relatively stable their since the deaths otherwise they would not be preserved. This is in stark contrast to the recent findings of bodies released by a glaciers in Europe. In Italy, the bodies of soldiers from World War I have been found not that far from a body dating from over 5000 years ago. It is clear from their release that the environment that preserves glaciers and their entombed dead is changing.
But it is not just the skeletal remains that tell us about past environments. Did the ancient Norse treat their dead to a funeral on a burning boat because they couldn't dig into the frozen ground? Did some burial traditions evolve to prevent public health problems? Even the new rules put out by the Vatican last week about handling the dead are responding to current environmental conditions. We have less room
for cemeteries and we are finding more compact ways to manage the ever increasing dead around us as our population continues to expand. How we handle the dead is a reflection, in part, of our current environmental condition.
|What might your grave contents tell us about the present|
environment? Click for photo credit.
Think about how the environment impacts the choices you make about your remains and how the environment will be impacted by your choices. What will archaeologists and other scientists find out about our times based on the choices that you make?