The most likely reason for their powerful biceps was the long, grueling hours they spent grinding grain, tilling soil and fetching food and water for livestock, say the study’s authors.
In other words, the women’s days were full of highly physically demanding work.
“Our findings suggest that for thousands of years, the rigorous manual labour of women was a crucial driver of early farming economies,” said Jay Stock, the study’s senior author and an archeologist at the University of Cambridge in Great Britain, in a released statement (with British spellings).
As background information in the paper points out, scientists know little about the nature and scale of the physical demands placed on women during the early days of farming — from about 7,500 years ago until about 2,500 years ago — because past research has tended to focus on men. Indeed, Stock and his colleagues say this is the first study to compare the bones of prehistoric women to those of living women.
Why is such a study important? Because “by interpreting women’s bones in a female-specific context we can start to see how intensive, variable and laborious their behaviors were, hinting at a hidden history of women’s work over thousands of years,” explained Alison Macintosh, the study’s lead author and an archeologist at Cambridge University, in the released statement.
Centuries of bones
For the study, the Cambridge University researchers analyzed the bones of women’s skeletons found in European cemeteries that date from the dawn of farming during the Neolithic era (as early as 5,300 B.C.) through the Middle Ages (as late as A.D. 850). The analysis included 78 upper arm (humerus) bones and 89 lower leg (tibia) bones.
Those bones were then compared with 81 arm bones and 78 leg bones of living young adult women, including runners, soccer players, rowers and a group who was not particularly athletic — all students at Cambridge University. These bones were analyzed with a small computed tomography (CT) scanner.
Much can be learned about an individual’s physical life from studying bones, the researchers stress. “It can be easy to forget that bone is a living tissue, one that responds to the rigours we put our bodies through,” said Macintosh. “Physical impact and muscle activity both put strain on bone, called loading. The bone reacts by changing in shape, curvature, thickness and density over time to accommodate repeated strain.”
The analysis revealed that women from the Neolithic period had similar leg bone strength as modern women, but their arm bones were significantly stronger — 30 percent stronger than the non-athletic Cambridge students and up to 16 percent stronger than those of the modern-day rowers.
That latter finding was striking, for rowing is a sport that requires repetitive upper arm movement. At the time of the study, the 17 student rowers whose arm bones were analyzed were training twice a day for an average of 74 miles a week, and they went on later that year to break a longstanding race record.
The Bronze Age women also had stronger arm bones than the modern rowers — up to 13 percent stronger, but their leg bones were 12 percent weaker, a finding that suggests women had become less mobile during this era, the researchers say.
The bones of the women from the Middle Ages, however, looked more like those of the modern rowers and other recreationally active women in the study. By that time, technological advances in farming tools would have required less arm strength, the Cambridge researchers explain.
The daily grind
The study’s authors can’t say with certainty why prehistoric women’s arms were so brawny, but they point to the grinding of grain into flour, which was a major activity in early agriculture and one probably performed by women, as a probably major cause.
“For millennia, grain would have been ground by hand between two large stones called a saddle quern,” explained Macintosh. “In the few remaining societies that still use saddle querns, women grind grain for up to five hours a day. The 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.”
But prehistoric women did plenty of other tasks that required strong arms.
“Prior to the invention of the plough, subsistence farming involved manually planting, tilling and harvesting all crops,” Macintosh said. “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.”
In other words, they were shouldering (literally) much of the hard physical labor that sustained their families and communities.
FMI: You can read the study on Science Advances’ website.