BioMed
Angela Saini examines how bias shaped science about women, from brain-size claims to unequal verdicts on identical résumés, alongside newer research.
When scientists rated résumés that were identical except for the applicant's name, those carrying a female name were judged less competent and less hireable. Trained, evidence-minded experts still let a name stand in for ability.
The sexes differ in health in a pattern no simple ranking captures: women suffer more illness, but men die younger. Having only one X chromosome leaves men more exposed to certain disorders, such as haemophilia and colour blindness.
The maternal instinct is assumed to be immediate and universal, but no biological rule makes women natural homemakers. What looks innate is often trained early, as when children are steered toward trucks or dolls and adults then delight in the 'natural' preference.
A measured average difference gets read as proof of who is superior, even when it says nothing about ability. Women's brains weighing a few ounces less than men's on average was once taken as evidence of men's greater intelligence.
In living foraging societies women often hunt, and the division of labour by sex is far less strict than the hunter-gatherer story claims. In many of these groups women bring back more food than men.
Male control may not be a fixed feature of human nature but a later social arrangement. One view holds that when people settled into farming, men formed social ties that shut women out.
Female promiscuity can be a strategy, not an anomaly. Some female monkeys mate with several males so that no male can be sure he is not the father, which makes males less likely to kill infants.
Scientists are not neutral judges; the method can carry the biases of the people who run it. When an institution excludes women for centuries, its conclusions about women tend to confirm the exclusion that produced them.
Our picture of the past is built from what survives, so work done with perishable tools drops out of the story. Stone spearheads last while baskets, baby slings and digging sticks rot, which makes 'man the hunter' look like the whole of early life.
Discredited gender stereotypes keep coming back dressed as new science. Claims that women are naturally choosy and monogamous while men are promiscuous, or that girls are born empathisers and boys born systemisers, echo older beliefs more than they follow from firm evidence.