In the twentieth century, the big-brained female — femina sapiens — found herself living in an utterly reshaped habitat, Kay S. Hymowitz reminds us:
“Consider a typical woman born around 1900,” [Stefania Albanesi and Claudia Olivetti] write. “She married at 21 and gave birth to more than three live children between age 23 and 33. The high fetal mortality rate implied an even greater number of pregnancies, so that she would be pregnant for 36 percent of this time. Health risks in connection to pregnancy and childbirth were severe. Septicemia, toxaemia, hemorrhages and obstructed labor could lead to prolonged physical disability and, in the extreme, death.” It wasn’t just the Pill, then; antibiotics, blood banks, improvements in prenatal and obstetric care, and the mass production of safe baby formula fundamentally altered the human environment in ways that laid the foundation for contemporary women’s achievement.Machinery invented by the brainy Homo sapiens also revolutionized the female lot. Until 1900, the vast majority of people in the Western world lived in conditions much like those in sub-Saharan Africa and parts of the Middle East today. Few had access to electricity; only about a quarter of all American households had running water. In this environment, American women did what women tied to their domiciles with three-plus children have always done: cooking, making and cleaning clothes, hauling water, and the like. But by the mid-twentieth century, human innovation had considerably lightened those essential household tasks. Using U.S. Census data, University of Montreal economist Emanuela Cardia has shown how home technology, including appliances and bathroom plumbing, played a significant role in moving women into the labor force.