Dr. Evan
Peacock, sorting land snails under a high power microscope
in the Environmental Archaeology Laboratory, Mississippi
State University.
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Environmental archaeologists study how humans
relate to the environment over the long term: over decades, centuries,
or even millennia. Understanding past cultures depends upon understanding
what sort of physical settings people inhabited in the past. For
example, large parts of what is now the Sahara desert in north
Africa were once lush grasslands teeming with animal life. Obviously,
the prehistoric groups living there at the time had a much different
lifestyle than later nomadic groups who contended with dry desert
conditions. Environmental archaeologists also study the impacts
that pre-industrial peoples had upon the landscape. Those impacts
could be profound. Ancient Polynesians, for example, knowingly
or unknowingly caused the extinction of numerous species of birds
as the Pacific islands were colonized in prehistoric times. The
vast, treeless expanse of Dartmoor, in southern England, boasted
a dense forest before Neolithic sheepherders cleared the land
for grazing thousands of years ago.
In order to reconstruct past environments, the
remains of plants and animals are retrieved from the soil and
analyzed in the Environmental Archaeology Laboratory at the Cobb
Institute of Archaeology, Mississippi State University. The habitat
requirements of the species thus identified are used to assess
what environmental conditions were like at the site where the
remains were found. The types of remains currently being analyzed
at MSU include freshwater mussels, land snails, pollen, charred
plant remains, and insects.
One current project* funded by the National Science
Foundation involves analyzing thousands of land snails from Native
American sites around Starkville, Mississippi. Beginning about
1000 years ago, groups in the area adopted an agricultural lifestyle,
growing maize and other crops on the thin, upland soils. Today,
those soils are covered with a cedar-dominated woodland, but evidence
suggests that in the past the hill tops were covered with stands
of oak and hickory. As the landscape changes, so too do the snail
species occupying the landscape. Dr.
Evan Peacock, with the aid of student workers, is studying
the snails to determine when this dramatic change in environmental
conditions occurred, and whether it was initiated by prehistoric
Native American farming practices. Research over the next few
years should shed light on how the fragile prairie ecosystem of
the Starkville area was altered by human activities in the past.
Another NSF-funded project** is allowing the investigation
of environmental conditions during the hypsithermal period in
the Southeast. The hypsithermal was a time when the climate was
warmer and drier than at present. The effects of this environmental
change on Native cultures are poorly understood. With the help
of a graduate student assistant, Dr. Peacock is looking a mussel
shells from a site on the Tombigbee River that was occupied during
the hypsithermal and subsequent periods. If the river was markedly
different in terms of depth and current flow during the hypsithermal,
then the mussels taken from the river during that time should
be different in size and shape that mussels taken later in time.
If successful, this method should have broad application throughout
eastern North America, where shell midden sites are common.
Dr. Peacock also is using mussel shell as a way
of sourcing prehistoric ceramics. Beginning about one thousand
years ago, Native Americans in the Southeast began adding crushed
mussel shell to their pottery as a tempering agent. Because mussels
from different rivers are chemically distinct, it should be possible
to see where pottery was made by analyzing the shell temper particles
for their elemental content. Dr. Peacock is working with other
scientists to develop a method of analyzing shell temper using
what is essentially a non-destructive, laser-based system.
*This material is based upon work supported by the
National Science Foundation under Grant No. 0003833. Any opinions, findings,
and conclusions or recommendations expressed in this material are those of the
author(s) and do not necessarily reflect the views of the National Science Foundation.
**This material is based upon work supported by the National Science Foundation
under Grant No. 0233837. Any opinions, findings, and conclusions or recommendations
expressed in this material are those of the author(s) and do not necessarily reflect
the views of the National Science Foundation.
