The invention of the plough allowed humanity to plant crops on hard and stony soil. But it has also helped enslave generations of women, a group of US economists has claimed. The roots of inequality have taken hold in soil of our own preparing, they argue.

In their research, the economists found a major difference between women's roles in societies that were descended from farming communities that used ploughs and those whose ancestors used hoes. These two different tilling techniques, although introduced long ago, have produced major divisions in modern society, say Alberto Alesina and Nathan Nunn of Harvard University, and Paola Giuliano of UCLA. Crucially, these divisions have survived immigration and persist even in cities and towns.

In those societies that relied on ploughs to prepare the ground, women are today less likely work outside the home, be elected to parliament or run businesses, the groups states. "The descendants of societies that traditionally practised plough agriculture, today have lower rates of female participation in the workplace, in politics, and in entrepreneurial activities, as well as a greater prevalence of attitudes favouring gender inequality," they state in a paper published by the US National Bureau of Economic Research.

Ploughs are used to prepare the ground when large tracts of land are needed for growing crops such as wheat, barley and rye. By contrast, hoes are used in communities that rely on sorghum, millet, root and tree crops. These require less land and can be cultivated – using hoes – on thin, sloped or rocky soils, state the authors.

Women often played a significant role in tending the land in the distant past. But when ploughs were introduced in various regions, men were placed at an advantage. Working with ploughs and the animals used to pull them required considerable strength. Women were sidelined and kept housebound. Typical plough-using societies include those found in Pakistan, India and Egypt.

By contrast, societies in which hoeing is common are found in African countries such as Burundi, Rwanda, and Kenya. Women here continue to have significant roles in working on the land because hoeing does not require the use of heavy force. In Burundi, women make up 90% of the country's agricultural workforce, for example. By contrast the figure in Pakistan is 16%.

Basing their analysis on studies of more than 1,200 different language groups from round the world, the authors found that societies and ethnic groups descended from plough-using peoples were significantly more likely to agree with statements that men should have first choice of jobs and that men make better political leaders. These attitudes persist even when the people have emigrated to western nations.

However, these beliefs are not necessarily fixed for ever. Many countries in the west were once populated by plough-using communities but do not insist on such divisions between the roles of the sexes, add the authors. Nevertheless, their message is clear: attitudes to the roles of women in the workplace have deep roots.