Stable isotopes as a fingerprint of human behaviour : analysis of human archaeological cremains : problems and perspectives

One of the basic methods used in investigating migration processes is the analysis of stable oxygen and strontium isotopes. This method was introduced to archaeo- -anthropological studies from zoological research, who first applied it to tracing animal migrations. Stable isotope analyses in origin and migration studies are based on the premise that the isotope ratios in osteological material almost precisely reflect the isotope composition of the environment (water and soil) inhabited by the group. If the bone material of a given individual reveals any departure from oxygen and strontium isotope ratio relative to the local level, it is possible to speak of its allochthonic origin. In addition, the discrepancy between the isotope ratio in bone tissue and tooth enamel allows us to isolate from the group individuals who had spent childhood in a place different from where the remains were found. Isotope studies using cremated remains are still a largely unexplored field. The fact that high temperature causes changes in the isotopic composition of the bone tissue unconditionally excludes incinerated bone material from such analyses. This problem has only recently been addressed once again and more and more works, usually model studies, attempt to explain how heat and duration of the incineration affect final concentrations of stable isotopes in bones, which may result in designing a standardised method for analysing stable isotopes in cremated material, e.g. from the Bronze Age cemeteries, in the future

Strontium isotopes as an indicator of human migration : easy questions, difficult answers

Isotope analyses of bones and teeth allow us to study phenomena which occurred in the history of human species and which are difficult to capture by traditional anthropological methods. Measuring oxygen, nitrogen and carbon isotope levels in the skeleton makes it possible to reconstruct climatic changes, diet and/or the weaning process. Among isotopes used in such analyses are strontium isotopes, helpful in analysing migration and studying the mobility of historical and prehistoric human populations. In this respect, the proportion of two isotopes, the heavier 87Sr and the lighter 86Sr, is measured, following their extraction from the bioapatite of the bone mineral. Released from rocks in the weathering process, strontium permeates individual components of inanimate and animate environments, and then finds its way, together with food, to the human body. Thanks to comprehensive environmental studies and the measurement of the strontium ratio 87Sr/86Sr in various animal tissues it is possible to determine the local isotope background for the environment. Values obtained by analysing human skeletons referenced against the range of environmental isotope variability enable researchers to trace back the location inhabited by the individual or group

The human bone oxygen isotope ratio changes with aging

The oxygen isotope ratio (\delta^{18}O) in tissues is the outcome of both climatic and geographical factors in a given individual’s place of abode, as well as the physiology and metabolism of his organism. During an individual’s life, various rates and intensities of physiological and metabolic processes are observable in the organism, also within the bone tissue. The aim of this study is to verify whether involutional changes occurring as a result of the organism’s ageing have a significant impact on \delta^{18}O determined in the bone tissue. The material used for analysis was fragments of the long bones taken from 65 people, (11 children and 54 adults), whose remains had been uncovered at the early mediaeval (X-XI century) cemetery located at the Main Market Square in Kraków (Poland). The correlation analysis between \delta^{18}O of bone tissue and an individual’s age shows that up to 40 years of age, such a relationship does not exist in both, males and females. However, the conducted correlation analysis prompted the observation that after 40 years of life, \delta^{18}O in bone tissue significantly drops as females increase in age. Results suggest that the\delta^{18}O in bone tissue among older people may be the outcome not only of environmental factors but also involutional changes in bone linked to an organism’s ageing. Therefore, the interpretation of \delta^{18}O results relating to the description of the origin and migrations of older individuals should be treated with caution

Oxygen isotopic fractionation in rat bones as a result of consuming thermally processed water : bioarchaeological applications

Stable isotope analyses of oxygen are used in anthropology for such purposes as determi-nation of origin of individuals, tracking migration routes or dynamics of human community reloca-tion. The methodology related to oxygen isotope analysis has been founded on the relationship between its isotopic composition within phosphate groups of bone tissue (\delta^{18}O_{p}) in individuals being analysed and the water consumed by such individuals (\delta^{18}O_{w}). Such a relationship has been observed in many species of mammals, including humans. However, the influence of culinary practices on the isotopic delta values of apatite phosphates of individuals has not yet been researched. The present study, which was conducted using laboratory rats, is an investigation of the influence of the thermal processing of water drank by such rats on the isotopic composition (\delta^{18}O_{p}) of bone apatite. Increasing the value of the isotopic composition of water by about 6.1 ‰ during boiling resulted in an increase in the oxygen isotopic value \delta^{18}O_{p} of rats drinking the water by about 4 ‰ (29%). It can be expected that regular consumption of heavily isotopic drinks and foods by humans may cause the \delta^{18}O_{p} of individuals to exceed the range of isotopic environmental variability, even by a few per mille

A new perspectives on breastfeeding practice reconstruction in bioarchaeology – an oxygen isotopes study in an animal model

Research using stable isotopes for the reconstruction of breastfeeding strategies are based on assumptions that have not yet been verified by experimental studies. Interpreting the results of isotope analysis is associated with a certain degree of uncertainty, mainly due to the lack of information on how isotopes are distributed in mothers, breast-fed and weaned offspring. Culinary practices also can affect the interpretation of isotope results.Considering positive correlation between oxygen isotope composition of drinking water and bone phosphates, experimental studies were carried out using rats as an animal model. The experiment showed that apatites of breast-fed offspring were enriched 1.6‰ in comparison to the values observed in their mothers. In the boiled water model, the difference was 1.8‰. On the basis of the animal model, it was estimated that the difference in 18O between mother and child in the human species may amount to approximately 2.7‰, and long-term intake of boiled liquid food and beverages will not compensate the difference.The experiment allowed observation of the effect of changes in isotope ratios to a change in trophic levels during breastfeeding and weaning, as well as the additional effect associated with the consumption of isotope enriched water during thermal treatment

Origin of the ornamented bâton percé from the Gołębiewo site 47 as a trigger of discussion on long-distance exchange among Early Mesolithic communities of Central Poland and Northern Europe

This article describes evidence for contact and exchange among Mesolithic communities in Poland and Scandinavia, based on the interdisciplinary analysis of an ornamented bâton percé from Gołębiewo site 47 (Central Poland). Typological and chronological-cultural analyses show the artefact to be most likely produced in the North European Plain, during the Boreal period. Carbon-14 dating confirms the antiquity of the artefact. Ancient DNA analysis shows the artefact to be of Rangifer tarandus antler. Following this species designation, a dispersion analysis of Early-Holocene reindeer remains in Europe was conducted, showing this species to exist only in northern Scandinavia and north-western Russia in this period. Therefore, the bâton from Gołębiewo constitutes the youngest reindeer remains in the European Plain and south-western Scandinavia known to date. An attempt was made to determine the biogeographic region from which the antler used to produce the artefact originates from. To this end, comprehensive δ18O, δ13C and δ15N isotope analyses were performed. North Karelia and South Lapland were determined as the most probable regions in terms of isotopic data, results which correspond to the known distribution range of Rangifer tarandus at this time. In light of these finds, the likelihood of contact between Scandinavia and Central Europe in Early Holocene is evaluated. The bâton percé from Gołębiewo is likely key evidence for long-distance exchange during the Boreal period