Isotopes are atoms of a certain element that have the same number of protons but a different number of neutrons, resulting in different masses. Isotopic analysis is the practice in which isotopes are separated and studied on the basis of their differences in mass. This study is conducted through the use of mass spectrometry (Bronk, McCarthy 2008). Because unstable isotopes tend to degrade over time, stable isotopes are favored in isotope analysis. This is valuable to archaeologists because they can use it to study the movement of populations, diets, and past environments through ancient human remains (Blakemore 2019). 

Image 1. How Strontium enters the human body through specific diets. From the article “Isotope Analysis” published by PBS. 

Strontium is a popular subject for isotopic analysis in archaeology because it can determine “residential origins and migration patterns of ancestral humans” and is incorporated into the human body through diets (Dvoracek). Strontium isotopes can be obtained through tooth enamel and bones. The study of these isotopes is shown to be able to identify “more subtle shifts in prehistoric human mobility” (Giblin 2008). The analysis of strontium isotopes was employed on the Great Hungarian Plain, Alföld, to study the time period from the end of the Neolithic to the Copper Age. For this, Sr-86 and Sr-87 were analyzed. Before the application of strontium isotope analysis, archaeologists had reason to believe that there was a change in interaction between the people and the environment. For example, there is evidence that societies became increasingly more mobile, which could have been due to a transition to becoming an agro-pastoral economy, one in which “social organization [is] based on the growing of crops and the raising on livestock as the primary means of economic activity” (Giblin 2008; Hakansson, 1998).

The results of the strontium-isotope study in Hungary show that there was a big change in how societies interacted with the environment between the Neolithic Age and the Copper Age. The individuals from the late Neolithic population were proven to have less variability in their strontium isotopes compared to the Copper Age population, who had more variation (Giblin 2008). Archaeologists believe that this dramatic change in strontium presence can be attributed to a transformation in ways of life. In the late Neolithic period, settlements were large and  concentrated; contrastingly, Copper Age settlements were smaller and spread out over a greater distance. The change in social structures is consequently believed to have changed the mobility of societies, which further changed methods of agriculture and obtaining sustenance (Giblin 2008). 

Image 2. Results from the isotope analysis of Sr-86 and Sr-87 of people from the Late Neolithic period to the Copper Age. Circles = Late Neolithic; upward triangle = Early Copper Age; squares = Middle Copper Age. From the article “Strontium isotope analysis of Neolithic and Copper Age populations on the Great Hungarian Plain” (Giblin 2008). 

In the late Neolithic period, there was a dramatic increase in large game hunting and the consumption of cattle. In the Copper Age, hunting became less popular as there was a shift to a more systematic way of raising stock such as pigs, sheep, and goats. After the analysis of pig strontium isotopes, it has been determined that they have a wider range of values. The increased consumption of pigs in the Copper Age population’s diet would contribute to their higher level of strontium-isotope variability (Giblin 2008).

References:

“Isotope Analysis.” PBS. Public Broadcasting Service. Accessed November 13, 2022. http://timeteam.lunchbox.pbs.org/time-team/experience-archaeology/isotope-analysis/.