Bones of Roman Britons provide new clues to dietary deprivation

Researchers at the University of Bradford have shown a link between the diet of Roman Britons and their mortality rates for the first time, overturning a previously-held belief about the quality of the Roman diet.

Bones of Roman Britons provide new clues to dietary deprivation
A soldier’s tombstone from Roman-era London
[Credit: Museum of London]

Using a new method of analysis, the researchers examined stable isotope data (the ratios of particular chemicals in human tissue) from the bone collagen of hundreds of Roman Britons, together with the individuals’ age-of-death estimates and an established mortality model.

The data sample included over 650 individuals from various published archaeological sites throughout England.

The researchers — from institutions including the Museum of London, Durham University and the University of South Carolina — found that higher nitrogen isotope ratios in the bones were associated with a higher risk of mortality, while higher carbon isotope ratios were associated with a lower risk of mortality.

Romano-British urban archaeological populations are characterised by higher nitrogen isotope ratios, which have been thought previously to indicate a better, or high-status, diet. But taking carbon isotope ratios, as well as death rates, into account showed that the nitrogen could also be recording long-term nutritional stress, such as deprivation or starvation.

Differences in sex were also identified by the researchers, with the data showing that men typically had higher ratios of both isotopes, indicating a generally higher status diet compared to women.

Dr Julia Beaumont of the University of Bradford said: «Normally nitrogen and carbon stable isotopes change in the same direction, with higher ratios of both indicating a better diet such as the consumption of more meat or marine foods. But if the isotope ratios go in opposite directions it can indicate that the individual was under long-term nutritional stress. This was corroborated in our study by the carbon isotope ratios which went down, rather than up, where higher mortality was seen.»

During nutritional stress, if there is insufficient intake of protein and calories, nitrogen within the body is recycled to make new proteins, with a resulting rise in the ratio of nitrogen isotopes in the body’s tissues.

Dr Beaumont added: «Not all people in Roman Britain were high-status; there was considerable enslavement too and we know slaves were fed a restricted diet. Our research shows that combining the carbon and nitrogen isotope data with other information such as mortality risk is crucial to an accurate understanding of archaeological dietary studies, and it may be useful to look at existing research with fresh eyes.»

The paper is published in Annals of Human Biology.

Source: University of Bradford [September 10, 2019]

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Researchers find earliest evidence of milk consumption

Researchers have found the earliest direct evidence of milk consumption anywhere in the world in the teeth of prehistoric British farmers.

Researchers find earliest evidence of milk consumption
A jaw bone used in the study — from the collections of the Dorset County Museum
[Credit: Dr Sophy Charlton, University of York]

The research team, led by archaeologists at the University of York, identified a milk protein called beta lactoglobulin (BLG) entombed in the mineralised dental plaque of seven individuals who lived in the Neolithic period around 6,000 years-ago.

The human dental plaque samples in the study are the oldest to be analysed for ancient proteins to date globally and the study represents the earliest identification of the milk whey protein BLG so far.

The Neolithic period in Britain ran from 4,000 to 2,400 cal. BC and saw the emergence of farming, with the use of domesticated animals such as cows, sheep, pig and goats, alongside crops such as wheat and barley. Archaeologists have also discovered evidence of complex cultural practices, with Neolithic communities building large monumental and burial sites.

The ancient human remains tested in the study come from three different Neolithic sites — Hambledon Hill and Hazleton North in the south of England, and Banbury Lane in the East Midlands. Individuals from all three sites showed the presence of milk proteins from cows, sheep or goats, suggesting people were exploiting multiple species for dairy products.

Dental plaque can offer unique insights into the diets of ancient people because dietary proteins are entrapped within it when it is mineralised by components of saliva to form tartar or ‘dental calculus’.

Lead author of the study, Dr Sophy Charlton, from the Department of Archaeology at the University of York, said: «The fact that we found this protein in the dental calculus of individuals from three different Neolithic sites may suggest that dairy consumption was a widespread dietary practice in the past.

«It would be a fascinating avenue for further research to look at more individuals and see if we can determine whether there are any patterns as to who was consuming milk in the archaeological past — perhaps the amount of dairy products consumed or the animals utilised varied along the lines of sex, gender, age or social standing.»

The discovery of milk proteins is particularly interesting as recent genetic studies suggest that people who lived at this time did not yet have the ability to digest the lactose in milk. To get around this, the ancient farmers may have been drinking just small amounts of milk or processing it into other foodstuffs such as cheese (which removes most of the lactose), the researchers say.

‘Lactase persistence’, which allows for the continued consumption of milk into adulthood, is the result of a genetic mutation in a section of DNA that controls the activity of the lactase gene. However, the mechanisms behind how and when we evolved this ability remain a mystery.

Dr Charlton added: «Because drinking any more than very small amounts of milk would have made people from this period really quite ill, these early farmers may have been processing milk, perhaps into foodstuffs such as cheese, to reduce its lactose content.»

«Identifying more ancient individuals with evidence of BLG in the future may provide further insights into milk consumption and processing in the past, and increase our understanding of how genetics and culture have interacted to produce lactase persistence.»

The findings are published in the journal Archaeological and Anthropological Sciences.

Source: University of York [September 10, 2019]

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HiPOD 10 September 2019: Scandia Cavi Dunes   There are active…

HiPOD 10 September 2019: Scandia Cavi Dunes

   There are active dunes and potentially active formations called “transverse aeolian ridges” in this area. By tracking dune movement it would be possible to limit the migration rates of these ridges.

ID: ESP_055073_2570
date: 26 April 2018
altitude: 316 km

NASA/JPL/University of Arizona