Paleomobiliteit van mens en dier. Isotopenonderzoek in de Nederlandse archeologie.

Al meer dan dertig jaar worden methoden en tech-nieken uit de aardwetenschappen en de biologie met veel succes in de archeologie toegepast. Ook in Nederland gebeurt dat de afgelopen jaren op steeds grotere schaal. Naast het succesvolle dna-onderzoek aan archeologische resten wordt met name het isotopenonderzoek steeds vaker ingezet. Dit type onderzoek is veelbelovend gebleken bij het oplossen van vraagstukken met betrekking tot paleodieet en paleomobiliteit. Vooral de verhouding tussen de strontiumisotopen 87Sr en 86Sr geeft meer inzicht in de herkomst van (pre)historische individuen en de rol die paleomobiliteit in onze geschiedenis heeft gespeeld. Dit artikel gaat in op de werking van deze laatstgenoemde methodiek, die aan de hand van een voorbeeld uit de praktijk zal worden belicht

Sr–Pb isotope differences in pre- and post-burial human bone, teeth, and hair keratin: implications for isotope forensics

The isotopic signatures of human tissues can provide valuable information on geographic origin for medicolegal investigations involving unidentified persons. It is important to understand the impact of diagenetic processes on isotopic signatures, as alterations could result in incorrect estimation of geographic origin. This study examines alterations in isotope signatures of different tissues of five human body donors studied throughout decomposition at the Forensic Anthropology Research Facility (FARF), San Marcos, TX. Two body donors were buried, two were placed in open pits, and one was first allowed to naturally mummify and then buried. Remains were recovered after a period of 7–34 months. The preplacement and post-recovery Sr–Pb isotope data of scalp hair, bone (iliac and tibia), and tooth enamel and dentine were compared. The hair samples record significant shifts in Sr-Pb isotope compositions, with hair keratin Pb isotope composition shifting towards the Pb signature of local soil samples. Hair keratin Sr isotope compositions were altered by the burial environment and possibly also by the lab sample cleaning method. The spongy iliac bone samples show inconsistencies in the recoverability of the preplacement Sr–Pb isotope signatures. The post-placement signatures of the buried donors show slight elevation over preplacement signatures. The post-placement signatures of donors placed in open pits are significantly elevated. The tibia and dental samples record the most consistent isotopic data with the least alteration. These more densely mineralised elements show good recoverability of the preplacement isotope signatures in burials and open pits and are thus deemed better targets for forensic investigative purposes

Diet and urbanisation in medieval Holland.: Studying dietary change through carious lesions and stable isotope analysis

In the late medieval period, Holland experienced substantial socio-economic change. While the region was largely undeveloped prior to 1200 CE, the period after was characterised by extensive urbanisation and flourishing international trade, changes that would have impacted many aspects of life. This paper investigates the effect of these changes on diet by comparing skeletal collections from the early/central medieval rural village of Blokhuizen (800–1200 CE) to the late medieval urban town of Alkmaar (1448–1572 CE) using a combination of the prevalence and location of carious lesions (nteeth = 3475) and stable carbon and nitrogen isotope data (n = 50). Results show that the urban Alkmaar population had a significantly higher caries frequency (7.4% vs. 16.1%), starting at a younger age. Moreover, Alkmaar had significantly more approximal caries. These results point to increased consumption of cariogenic products, such as sugars and starches, by the urban citizens. Dietary differences are also demonstrated by the stable isotope data. Alkmaar individuals have significantly enriched δ15N ratios and more variable δ13C ratios compared with rural Blokhuizen. The elevated δ15N values may be due to increased consumption of fish or animals such as omnivorous pigs and chickens. The combination of caries and isotopic data points to clear changes in diet suggesting that urban individuals in the late medieval period had a substantially different diet compared with early rural inhabitants from the same area. Specifically, an increase in market dependence, availability of international trade products, and the growth of commercial fishing in the late medieval period may have contributed to this dietary shift. Future research should include a late medieval rural population to better understand the effects of late medieval socio-economic developments outside of the urban environment. This study demonstrates that the integration of palaeopathology and stable isotopic research provides a more complete understanding of dietary changes in medieval Holland.Stichting Nederlands Museum voor Anthropologie en PraehistorieBioarchaeolog

Tanden als tijdscapsules: isotopenonderzoek

Tanden en kiezen zijn voor de archeologie en de forensische wetenschap van buitengewoon veel waarde. Het zijn kleine tijdcapsules die door de toepassing van isotopenonderzoek geheimen prijsgeven over waar mensen vandaan komen, welke route ze in hun kinderjaren hebben afgelegd en wat voor voedsel zij gegeten hebben. Omdat gebitselementen zo resistent zijn tegen fysische degradatie en chemische veranderingen (diagenese) kunnen zelfs duizenden jaren oude gebitselementen nog informatie geven over menselijke populaties. Ook in de forensische wetenschappen wordt het isotopenonderzoek toegepast om informatie te krijgen over de herkomst van niet-geïdentificeerde individuen om zo het recherchewerk in een (nieuwe) richting te duwen. Het isotopenonderzoek is gebaseerd op de aanname ‘je bent wat je eet’. De isotopenratio’s van het geconsumeerde voedsel worden namelijk in het tandglazuur gereflecteerd. Een vergelijking van de isotopensamenstelling van het tandglazuur met de verwachte samenstelling van de geologische ondergrond kan inzicht geven in de herkomst van een individu