Tag: isotope

Animals, People, and Power in Ancient Sardinia

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Dr Emily Holt, Marie Curie Fellow
Cardiff University

When you think of archaeology, what do you imagine? Pyramids? Temples? Researchers in broad-brimmed hats scraping the ground with their trowels? What about animal bones – do animal bones come to mind when you picture archaeologists at work? 

Animal bones may not be the first thing you think of, but zooarchaeology – the study of animal remains in archaeological contexts – is a vibrant and informative part of archaeological research. Animal bones tell us all kinds of things about ancient people – not just what they ate, but also about their economies, political structures, home lives, and patterns of travel.  

I’m a zooarchaeologist studying the Nuragic Culture of Ancient Sardinia. The Nuragic Culture flourished during the Sardinian Bronze Age (c. 1700-900 BCE), when the Nuragic people built thousands of monumental stone towers called nuraghi all over their island. They built just a few hundred at first, expanding over the centuries to build thousands more, many of which were also larger and more architecturally complex than the early towers. These patterns of settlement expansion suggest that interesting processes of political consolidation were taking place, probably supported by changes in how Nuragic people used their natural resources. 

Studying the towers themselves can only tell us so much, however. Resources like animal bones excavated from inside and around the towers provide helpful additional evidence. My project ZANBA is using animal remains excavated from an early and a later Nuragic tower to look at changes in how much territory Nuragic leaders controlled. I’m going to do this by analyzing the strontium isotopes in the teeth of the domestic animals the Nuragic leaders ate and comparing them against the strontium isotopes in the regions around the two sites. 

Strontium isotopes come from the particular geology of a region and get into animal teeth through the food chain: plants take up strontium from groundwater and soil, herbivores absorb strontium through the plants they eat, and carnivores absorb strontium through the animals they consume. Fortunately, the strontium isotopes aren’t really changed by going through the food chain, so the isotopes in animal teeth at the end of the chain are closely related to the isotopes of the plants at the beginning. 

Sardinia has a highly varied geology, so the first part of my study is to map the strontium isotopes around my study area. I’ll do this by collecting plants from across the different geologies and testing their strontium isotopes. This will allow me to establish a base map of how strontium isotopes vary across my study area. Once I’ve completed the base map, I’ll test the strontium isotopes in the teeth of animals from my two sites and compare them with the base map.

This will allow me to identify where the animals that were eaten at the sites originally came from, which will give me an idea of how far the political power of these Nuragic leaders stretched. I expect to see an expansion of power between the early site and the later site, showing that Nuragic leaders were able to bring more territory under their control over time. 

Right now I’m in the early stages of my project, planning the best locations to collect plants to produce the most accurate and representative base map. The next step will be to travel to Sardinia and collect both the plant and animal specimens and bring them back to the lab to analyze with the help of my colleagues. If you’re interested in learning more about my research, you can check out my personal blog errant.live or follow @ZANBA_Project1 on Twitter and zanba_project on Instagram. 

Feasting and Mobility at Stonehenge

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Dr Richard Madgwick, Senior Lecturer
Cardiff University

Monumental complexes such as Stonehenge and Avebury represent some of the most famous prehistoric archaeological sites in the world. They often comprise sites of different character and function, with the Stonehenge complex having the stone circle of Stonehenge, a focus for funerary ritual, the wooden circle of Woodhenge and the henge enclosure of Durrington Walls, a centre for feasting and settlement.  

These monumental complexes have been a focus for archaeological and antiquarian research for centuries. The origins of the people who engaged in ceremonies at (and very likely built) Stonehenge and other great Late Neolithic (c. 2800-2400BC) monumental complexes represents a long-standing enigma in research on British prehistory. Isotope analysis provides a suite of methods for identifying non-local individuals and exploring origins through sampling bone and teeth. However, human remains at these sites are almost all cremated and therefore unsuitable for some forms of isotope analysis. Consequently, other proxies for human movement must be utilised. 

Sample of pig mandible from Durrington Walls

This study uses the bones and teeth of pigs, the prime feasting animal at these complexes. Tens of thousands have been recovered from Durrington Walls, providing a vital resource for reconstructing prehistoric lifeways. These are domestic pigs and therefore must have been brought by humans, thus potentially providing a good proxy for human movement. However, pigs are not considered well-suited to movement over distance and are commonplace in Late Neolithic Britain. Therefore, even if people came from far and wide, they might procure a pig in the vicinity of the henges to contribute to the feast, rather than going to the effort of bringing one that they themselves had raised. Pigs may therefore provide a weak proxy for human movement.    

The research analyses the largest five-isotope system faunal dataset yet published in archaeology. A total of 131 animals were analysed from four Late Neolithic complexes in Wessex: Durrington Walls, West Kennet Palisade Enclosures, Mount Pleasant and Marden. Each isotope system provides different information about the origins of the animals. Strontium (87Sr/86Sr) provides a geological signal, oxygen (d18O) a climatic signal and sulphur (d34S) an indication of coastal proximity. Carbon (d13C) and nitrogen (d15N) isotope analysis provides dietary information and represents an important baseline from which to interpret the other proxies. The combination of these isotope systems means that non-local animals can be identified with greater confidence and likely origins can in some instances be posited.  

Results were exceptionally wide-ranging in all of the provenancing isotope proxies. They are considered in the context of British origins, as there is no evidence for contact with continental Europe at this time. The strontium values encompassed the vast majority of biosphere variation that can be found in Britain from the youngest to oldest lithological zones. Oxygen values were suggestive of origins from the coastal west to the highland east and sulphur results indicated many animals were raised near the coast, with others having inland origins. No other British site of any period provides data as wide-ranging as for these Late Neolithic sites. On the basis of current mapping data, it is not possible to define origins with confidence, even when using multi-isotope proxies. Equifinality remains a hurdle to interpretation, as some areas may not be distinguishable. However, the scale of variation in all provenancing proxies provides convincing evidence for wide-ranging origins, and origins as far afield as Scotland cannot be discounted. It is not only the famous megalithic centres like Stonehenge that were major foci. All four sites show long-distance connectivity, and there is no indication that they served different networks; all drew people and animals from across Britain for this feasting events. 

These findings have major ramifications for how we understand Late Neolithic Britain. The monumental complexes of Wessex were not just power bases in the heartland of regional groups, at which feasting events acted to unify a disparate, yet broadly local populace, nor were they sites of reciprocal feasting, where alliances between neighbouring groups were forged and consolidated. These centres were lynchpins for a much greater scale of connectivity, involving disparate groups from across Britain. Results also suggest that prescribed contributions were required and that rules dictated that offered pigs must be raised by the feasting participants, accompanying them on their journey, rather than being acquired locally. The volume and scale of movement has not previously evidenced and it can be argued that the Late Neolithic was the first phase of pan-British connectivity. These long-distance networks were not only sustained by the movement of people but also of livestock. These results provide clear evidence for a great volume and scale of intercommunity mobility in Late Neolithic Britain, demonstrating a level of interaction and social complexity not previously appreciated. 

Original article: 

Madgwick R, Lamb A, Sloane H, Nederbragt A, Viner S, Albarella U, Parker Pearson M, Evans J.  2019. Multi-isotope analysis demonstrates long distance movement of people and animals for feasts in the Stonehenge landscape. Science Advances 5, eaau6078.