
For many people around the world, physical work takes up a lot of time and energy every day. But what determines whether men or women do more household work?
In most hunter-gatherer societies, the men are the hunters and the women the gatherers – the men seem to go the furthest. But what about the distribution of labor in other societies?
We conducted a study of farming and herding groups on the Tibetan border in rural China, an area of great cultural diversity, to find out what factors really determine who works the hardest at home and why. Our results, published in Current Biologyreveals the gendered division of labor in various societies.
Most adults around the world are married. Marriage is a contract, so the union can be expected to have roughly equal costs and benefits for both parties.
However, unequal bargaining power in the household—for example, one person threatening divorce—may result in unequal contributions to the partnership.

When leaving home
We decided to test the hypothesis that after heterosexual marriages, leaving the area of birth to live with the spouse’s family may increase workload. In such marriages, the new person is usually not related to anyone in the new household and does not share a history.
If they don’t have blood relatives nearby, they can be at a disadvantage when it comes to bargaining power.
The most common form of marriage around the world is for women to be “dispersants” who leave their homes of origin, while men stay with their families in their homelands. This is known as patrilocality.
Neolocality – where both sexes separate at the time of marriage and the couple live in a new location away from both families – is another common practice in many parts of the world. Matrilocality – where women remain in the natal family while men move in with their wives and their families – is relatively rare.
And duolocality – when neither sex leaves the house, and husband and wife live separately – is seen very rarely.
Fortunately, in the various border areas of Tibet, all four of these different distribution patterns can be found in a variety of different ethnic groups.
Our study focused on rural villages from six different ethnic cultures. With our collaborators at Lanzhou University in China, we surveyed more than 500 people about their post-marital dispersion and had them wear an activity tracker (such as a Fitbit) to measure their workload.

Women work harder
Our first conclusion was that women worked much harder than men and contributed most of the fruits of this work to their families. This is evidenced by their own reports of how much they worked and their activity trackers.
Women averaged just over 12,000 steps per day, while men averaged just over 9,000. So men also worked hard, but less than women. They spent more time on leisure or social activities, or simply resting.
This may be partly because women are, on average, physically weaker than men, so their bargaining power may be lower. However, we also found that individuals (male or female) who separate in marriage to live away from their relatives have a higher workload than those who remain with their birth families.
So if you are a woman and you leave home (as most women around the world do), you suffer not only from missing your family, but also from the workload.
When both sexes split up and no one lives with their birth families, both sexes work hard (as there is little help from relatives) – but women still work harder. According to our research, perfect gender equality in workload occurs only in cases where men split and women do not.
These results help explain why women spread out around the world while men usually don’t. The distribution is particularly bad for men, adding about 2,000 more steps per day to their step count, while women only add about 1,000 steps per day.
Time and energy devoted to farming, herding, and homemaking compete with leisure. Thus, the high labor input of households in these rural areas may result in less leisure time.
From an evolutionary point of view, forgoing rest is not favorable unless it contributes to better fitness, such as improved offspring survival.
We don’t really know if it’s favorable in this case because it hasn’t been studied much. This may be true in poor and rural areas around the world, but less so in wealthy areas.

For example, in most urban areas, an inactive lifestyle is becoming more prevalent. And studies have shown that sedentary lifestyles are becoming a major public health problem among white-collar workers in such areas. They are linked to many chronic health conditions such as obesity, infertility and several mental health disorders.
Gender inequality in workload persists both inside and outside the home. Now, our study has provided an evolutionary perspective on why women are more likely than men to have high workloads.
But things are slowly changing. As women increasingly start families away from their partners and their families, their bargaining power increases. This is further reinforced by their increasing level of self-made wealth, education and independence.
Ultimately, these changes in many urban, industrial or post-industrial societies lead to men taking on an increasing workload.
Yuan Chen, PhD in Evolutionary Anthropology, UCL and Ruth Mace, Professor of Anthropology, UCL
This article is republished from The Conversation under a Creative Commons license. Read the original article.