For our purposes we are interested in the ratio of heavy (oxygen 18) to light (oxygen 16) isotopes.Drinking water in warm climates has more heavy isotopes (higher ratio) and in cold climates has more light isotopes (lower ratio).Isotopic analysis is used in a variety of fields across the sciences, such as Geology, Biology, Organic Chemistry, and Ecology.Archaeology, which is situated between the hard natural sciences and social sciences, has adapted the techniques developed in these fields to answer both archaeological and anthropological questions that span the globe over both time and space.Isotopic indicators of environment are most often investigated through the study of oxygen isotopes.Different oxygen isotope values are representative of hotter and drier climates, versus those that were colder and wetter.Isotopes and the Study of Environment Many scientific fields utilize isotopic analysis to study past climate and environment. It is important to determine the environmental setting of a particular time and place in order to gain a better understanding of the factors that could have influenced the way a community developed.
Once the collagen is extracted this is prepared and weighed for analysis in the mass spectrometer.
We can compare the oxygen isotopes ratio in teeth with that of drinking water from different regions and determine where a person might have lived, at the time their teeth formed.
Oxygen isotope analysis of dental enamel from the two burials at Amesbury indicate that the “Archer” came from a colder climate region than we find in Britain today, possibly from some where in central Europe - the dark blue-green area in the oxygen isotope map.
When archaeological bone material is poorly preserved there may not be enough surviving biological material left for the analysis to be reliable.
However, in cases where the bones are well preserved, the isotopic signatures are considered to be representative of the individual specimen (either human or animal) that is being studied.