̽��ֱ�� of Cambridge - Alison Macintosh

Prehistoric women’s manual work was tougher than rowing in today’s elite boat crews

fpjl2 — Wed, 29 Nov 2017 19:01:03 +0000

A new study comparing the bones of Central European women that lived during the first 6,000 years of farming with those of modern athletes has shown that the average prehistoric agricultural woman had stronger upper arms than living female rowing champions.

Researchers from the ̽��ֱ�� of Cambridge’s Department of Archaeology say this physical prowess was likely obtained through tilling soil and harvesting crops by hand, as well as the grinding of grain for as much as five hours a day to make flour.

Until now, bioarchaeological investigations of past behaviour have interpreted women’s bones solely through direct comparison to those of men. However, male bones respond to strain in a more visibly dramatic way than female bones.

̽��ֱ��Cambridge scientists say this has resulted in the systematic underestimation of the nature and scale of the physical demands borne by women in prehistory.

“This is the first study to actually compare prehistoric female bones to those of living women,” said Dr Alison Macintosh, lead author of the study published today in the journal Science Advances.

“By interpreting women’s bones in a female-specific context we can start to see how intensive, variable and laborious their behaviours were, hinting at a hidden history of women’s work over thousands of years.”

̽��ֱ��study, part of the European Research Council-funded ADaPt (Adaption, Dispersals and Phenotype) Project, used a small CT scanner in Cambridge’s PAVE laboratory to analyse the arm (humerus) and leg (tibia) bones of living women who engage in a range of physical activity: from runners, rowers and footballers to those with more sedentary lifestyles.

̽��ֱ��bones strengths of modern women were compared to those of women from early Neolithic agricultural eras through to farming communities of the Middle Ages.

“It can be easy to forget that bone is a living tissue, one that responds to the rigours we put our bodies through. Physical impact and muscle activity both put strain on bone, called loading. ̽��ֱ��bone reacts by changing in shape, curvature, thickness and density over time to accommodate repeated strain,” said Macintosh.

“By analysing the bone characteristics of living people whose regular physical exertion is known, and comparing them to the characteristics of ancient bones, we can start to interpret the kinds of labour our ancestors were performing in prehistory.”

Over three weeks during trial season, Macintosh scanned the limb bones of the Open- and Lightweight squads of the Cambridge ̽��ֱ�� Women’s Boat Club, who ended up winning this year’s Boat Race and breaking the course record. These women, most in their early twenties, were training twice a day and rowing an average of 120km a week at the time.

̽��ֱ��Neolithic women analysed in the study (from 7400-7000 years ago) had similar leg bone strength to modern rowers, but their arm bones were 11-16% stronger for their size than the rowers, and almost 30% stronger than typical Cambridge students.

̽��ֱ��loading of the upper limbs was even more dominant in the study’s Bronze Age women (from 4300-3500 years ago), who had 9-13% stronger arm bones than the rowers but 12% weaker leg bones.

A possible explanation for this fierce arm strength is the grinding of grain. “We can’t say specifically what behaviours were causing the bone loading we found. However, a major activity in early agriculture was converting grain into flour, and this was likely performed by women,” said Macintosh.

“For millennia, grain would have been ground by hand between two large stones called a saddle quern. In the few remaining societies that still use saddle querns, women grind grain for up to five hours a day.

“ ̽��ֱ��repetitive arm action of grinding these stones together for hours may have loaded women's arm bones in a similar way to the laborious back-and-forth motion of rowing.”

However, Macintosh suspects that women’s labour was hardly likely to have been limited to this one behaviour.

“Prior to the invention of the plough, subsistence farming involved manually planting, tilling and harvesting all crops,” said Macintosh. “Women were also likely to have been fetching food and water for domestic livestock, processing milk and meat, and converting hides and wool into textiles.

“ ̽��ֱ��variation in bone loading found in prehistoric women suggests that a wide range of behaviours were occurring during early agriculture. In fact, we believe it may be the wide variety of women’s work that in part makes it so difficult to identify signatures of any one specific behaviour from their bones.”

Dr Jay Stock, senior study author and head of the ADaPt Project, added: “Our findings suggest that for thousands of years, the rigorous manual labour of women was a crucial driver of early farming economies. ̽��ֱ��research demonstrates what we can learn about the human past through better understanding of human variation today.”

̽��ֱ��first study to compare ancient and living female bones shows that women from early agricultural eras had stronger arms than the rowers of Cambridge ̽��ֱ��’s famously competitive boat club. Researchers say the findings suggest a “hidden history” of gruelling manual labour performed by women that stretched across millennia.

By interpreting women’s bones in a female-specific context we can start to see how intensive, variable and laborious their behaviours were

Alison Macintosh

Prehistoric women’s manual work was tougher than rowing in today’s elite boat crews

Alastair Fyfe for the ̽��ֱ�� of Cambridge

Cambridge ̽��ֱ�� Women’s Boat Club Openweight crew rowing during the 2017 Boat Race on the river Thames in London. ̽��ֱ��Cambridge women’s crew beat Oxford in the race. ̽��ֱ��members of this crew were among those analysed in the study.

̽��ֱ��text in this work is licensed under a Creative Commons Attribution 4.0 International License. For image use please see separate credits above.

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From athletes to couch potatoes: humans through 6,000 years of farming

amb206 — Tue, 08 Apr 2014 09:00:10 +0000

Human bones are remarkably plastic and respond surprisingly quickly to change. Put under stress through physical exertion – such as long-distance walking or running – bones gain in strength as the fibres are added or redistributed according to where strains are highest. ̽��ֱ��ability of bone to adapt to loading is shown by analysis of the skeletons of modern athletes, whose bones show remarkably rapid adaptation to both the intensity and direction of strains.

Because the structure of human bones can inform us about the lifestyles of the individuals they belong to, they can provide valuable clues for biological anthropologists looking at past cultures. Research by Alison Macintosh, a PhD candidate in Cambridge ̽��ֱ��’s Department of Archaeology and Anthropology, shows that after the emergence of agriculture in Central Europe from around 5300 BC, the bones of those living in the fertile soils of the Danube river valley became progressively less strong, pointing to a decline in mobility and loading.

Macintosh will present some of her results at the Annual Meeting of the American Association of Physical Anthropologists in Calgary, Alberta on 8-12 April, 2014. She will show that mobility and lower limb loading in male agriculturalists declined progressively and consistently through time and were more significantly affected by culture change in Central Europe than they were in females.

Work published by biological anthropologist Dr Colin Shaw (also Cambridge ̽��ֱ��) has enabled Macintosh to interpret this male decline in relation to Cambridge ̽��ֱ�� students. Using Shaw’s study of bone rigidity among modern Cambridge ̽��ֱ�� undergraduates, Macintosh suggests that male mobility among earliest farmers (around 7,300 years ago) was, on average, at a level near that of today’s student cross-country runners. Within just over 3,000 years, average mobility had dropped to the level of those students rated as sedentary, after which the decline slowed.

“Long-term biomechanical analyses of bones following the transition to farming in Central Europe haven’t been carried out. But elsewhere in the world they show regional variability in trends. Sometimes mobility increases, sometimes it declines, depending on culture and environmental context. After the transition to farming, cultural change was prolonged and its pace was rapid. My research in Central Europe explores whether – and how – this long term pressure continued to drive adaptation in bones,” said Macintosh.

Archaeological evidence has shown that the gradual intensification of agriculture was accompanied by rising production and complexity of metal goods, technological innovation and the extension of trade and exchange networks. “These developments are likely to have brought about changes in divisions of labour by sex and socioeconomic organisation as men and women began to specialise in certain tasks and activities – such as metalworking, pottery, crop production, tending and rearing livestock,” said Macintosh.

“I’m interested in how the skeleton adapted to people's specific behaviours during life, and how this adaptation can be used to reconstruct long-term changes in behaviour and mobility patterns with cultural diversification, technological innovation, and increasingly more complex and stratified societies since the advent of farming.”

As a means of tracking changes in the structure of bones over time, Macintosh laser-scanned skeletons found in cemeteries across Central Europe, concentrating in particular on an analysis of engineering-based cross-sectional geometric properties as measures of the loading imposed on the lower limb bones during life. Her research took her to Germany, Hungary, Austria, the Czech Republic and Serbia. ̽��ֱ��earliest skeletons she examined date from around 5300 BC and the most recent from around 850 AD – a time span of 6,150 years.

Using a portable desktop 3D laser surface scanner to scan femora and tibiae, she found that male tibiae became less rigid and that bones in both males and females became less strengthened to loads in one direction more than another, such as front-to-back in walking. These findings all indicate a drop in mobility. In other words, it is likely that the people to whom the skeletons belonged became, over generations, less intensely active and probably covered less distance, or carried out less physically demanding tasks, than those who had lived before them.

“Both sexes exhibited a decline in anteroposterior, or front-to-back, strengthening of the femur and tibia through time, while the ability of male tibiae to resist bending, twisting, and compression declined as well,” said Macintosh.

“My results suggest that, following the transition to agriculture in Central Europe, males were more affected than females by cultural and technological changes that reduced the need for long-distance travel or heavy physical work. This also means that, as people began to specialise in tasks other than just farming and food production, such as metalworking, fewer people were regularly doing tasks that were very strenuous on their legs."

Although there was some evidence for declining mobility in females as well, trends were inconsistent through time in most properties. Macintosh believes that this variation may indicate that women in these early farming cultures were performing a great variety of tasks – multi-tasking, in fact – or at least undertaking fewer tasks necessitating significant lower limb loading. There is evidence from two of the earliest cemeteries studied that females were using their teeth in processing activities to carry out tasks unlikely to have loaded their lower limbs much.

Interesting comparisons can be made between the archaeological evidence from Central European skeletons dating from around 7,300-1,150 years ago and data from modern farming populations elsewhere in the world.

A study by Panter-Brick in 1996 found that relative workload (as exhibited by time allocation and energy expenditure) between males and females in modern farming populations is much more variable than in foraging groups. As in early Central European farming communities, higher physical activity is recorded among males than females in Indian and Nepalese farming communities, but females have a higher relative workload than males in farming communities in the Upper Volta and the Gambia.

“This variability in the sexual division of labour in living agro-pastoralist groups shows the importance of context, ecology, and various cultural factors on sex differences in physical activity. So it is important when studying long-term trends in behavioural change between the sexes that the geographic region is kept small, to help control for some of this variability,” said Macintosh.

Female skeletons showed a major change in femoral bending and torsional rigidity from the Bronze Age into the Iron Age – between about 1450 BC and 850 BC in the samples studied – when women had the strongest femora of all the females examined in the study. This could be because the Iron Age sample included skeletons of Hungarian Scythians, a group for whom large animal husbandry, horsemanship and archery were particularly important. Scythian females are thought to have performed heavy physical work and were known to participate in at combat.

“However, if this high Iron Age female bone strength in the femur was due to high mobility, it would also probably be visible in the tibia as well, which it was not. In that case, it could be something other than mobility that is driving this Iron Age female bone strength, possibly a difference in body size or genetics,” said Macintosh.

Because the skeleton holds a record of the loading it experiences during life, it can provide important clues as to the behaviour of past people through prolonged cultural change. Overall, in the first 6,150 years of farming in Central Europe, the prosperity generated by intensive agriculture drove socioeconomic change and allowed for people to specialise in tasks other than food production.

Macintosh said: "In Central Europe, adaptations in human leg bones spanning this time frame show that it was initially men who were performing the majority of high-mobility tasks, probably associated with tending crops and livestock. But with task specialisation, as more and more people began doing a wider variety of crafts and behaviours, fewer people needed to be highly mobile, and with technological innovation, physically strenuous tasks were likely made easier. ̽��ֱ��overall result is a reduction in mobility of the population as a whole, accompanied by a reduction in the strength of the lower limb bones."

Inset images: Cambridge ̽��ֱ�� cross-country runners (Cambridge ̽��ֱ�� Hare & Hounds); 3D model of an Early Neolithic femur; Bronze Age infant urn burial from Ostojićevo, National Museum of Kikinda in Serbia; wheatfield in modern day Kikinda, northern Serbia (all Alison Macintosh)

Research into lower limb bones shows that our early farming ancestors in Central Europe became less active as their tasks diversified and technology improved. At a conference today, Cambridge ̽��ֱ�� anthropologist Alison Macintosh will show that this drop in mobility was particularly marked in men.

My results suggest that, following the transition to agriculture in Central Europe, males were more affected than females by cultural and technological changes.

Alison Macintosh

Moravian Museum

Early Neolithic 35-40 year old male from Vedrovice, Czech Republic

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