Read about six trailblazing women in science history…


Caroline Kennard (1827–1907)

American amateur scientist Caroline Kennard was a prominent member of her local women’s movement in Boston, Massachusetts, who pushed to raise the status of women in society. After hearing another woman use naturalist Charles Darwin’s evolutionary theory, laid out in On the Origin of the Species (1859), to support the view that “the inferiority of women: past, present and future was based upon scientific principles”, Kennard wrote to Darwin in December 1881, encouraging him to clarify that this was clearly not the case.

However, an ageing Darwin’s response revealed that he, too, believed that women were biologically inferior, even less evolved than men, writing: “I certainly think that women though generally superior to men [in] moral qualities are inferior intellectually.” For women to overcome this biological inequality, he added, they would have to become breadwinners like men, and this wouldn’t be a good idea, because it might damage young children and the happiness of households.

Kennard’s response to Darwin’s note sent in January 1882 was furious, arguing that women contribute just as much to society as men, and that the difference between men and women wasn’t the amount of work they did but the kind of work they were allowed to do. “Let the ‘environment’ of women be similar to that of men,” she wrote, “and with his opportunities, before she be fairly judged, intellectually his inferior, please.”

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Eliza Burt Gamble (1841–1920)

Growing up, Eliza Burt Gamble from Concord, Michigan, had little choice but to be independent. She lost her father when she was two years old and her mother when she was 16. Left without support, she made a living by teaching at local schools. She later married and had three children, two of whom died before the 19th century was out. She could have been a quiet, submissive housewife – instead, she joined the growing suffrage movement to fight for the equal rights of women, organising the first women’s suffrage conference in her home state of Michigan in 1876.

One of the biggest sticking points in the fight for women’s rights, she recognised, was that society had come to believe that women were born to be lesser than men. Convinced this was a fallacy, she set out to find hard proof for herself – and studied the evolutionary theory of Charles Darwin. Through her studies, Gamble came to believe that Darwin, though correct in concluding that humans evolved like every other living thing on earth, was wrong when it came to the role that women played in human evolution.

English naturalist Charles Darwin
English naturalist Charles Darwin in 1877. (Photo by adoc-photos/Corbis via Getty Images)

Her criticisms were passionately laid out in a book she published in 1894, called The Evolution of Woman: An Inquiry into the Dogma of Her Inferiority to Man, which angrily pointed out the inconsistencies and double standards of history, statistics and science and was a piercing counter-argument to Darwin and other evolutionary biologists. For instance, Darwin argued that gorillas were too big and strong to become higher social creatures like humans; yet at the same time he used the fact that men are, on average, physically bigger than women as evidence of their superiority.

He also failed to notice, Gamble wrote, that the human qualities more commonly associated with women – cooperation, nurture, protectiveness, egalitarianism and altruism – must have played a pivotal role in human progress. In evolutionary terms, she argued, drawing assumptions about women’s abilities from the way they happened to be treated by society at that moment was narrow-minded and dangerous. Women had been systematically suppressed over the course of human history by men and their power structures, Gamble argued. They weren’t naturally inferior; though they just seemed that way because they hadn’t been given the chance to develop their talents.


Helen Hamilton Gardener (1853–1925)

An American teacher and writer, Helen Hamilton Gardener was a passionate advocate for the rights of women, and was incensed by the scientific ‘facts’ that were being used to hold women back in their fight for equality.

Suffragist, writer and reformer Helen Hamilton Gardener. (Photo by Library of Congress/Corbis/VCG via Getty Images)
Suffragist, writer and reformer Helen Hamilton Gardener. (Photo by Library of Congress/Corbis/VCG via Getty Images)

In 1888 she gave a talk titled ‘Sex in Brain’ at the convention of the International Council of Women in Washington DC, in which she argued against American physician William Alexander Hammond’s claim, made in the magazine Popular Science Monthly in April 1887, that because women’s brains were lighter than men’s, by extension, women must also be less intelligent.

However, Gardener realised she didn’t have the education she needed to prove Hammond wrong, writing later in her book Facts and Fictions of Life (1893) that “I finally, with fear and trembling, made up my mind to learn what he knew on this subject or perish in the attempt.”

It took her 14 months to dissect William Hammond’s statistics while corresponding with 20 anatomists and doctors across New York. Gardener’s research demonstrated that not one of her experts could distinguish between a male and female brain at birth. Indeed, as she correctly reasoned, if absolute brain size were an indicator of greater intelligence, then whales would be the smartest species, not humans. It is relative brain size that matters, she concluded.

The debate around sex differences in the brain was not resolved during her lifetime, but she promised to leave her brain to science after she died. Today it is well established that brain size is related to body size – and not a direct indicator of intelligence. But that hasn’t stopped scientists, even today, combing brains for evidence that women think differently to men.


Nettie Maria Stevens (1861–1912)

American biologist Nettie Maria Stevens played a crucial role in identifying the chromosomes that determine sex, and yet her contributions remain largely ignored by history.

American biologist Nettie Marie Stevens. (© By The Incubator, courtesy of Carnegie Institution of Washington. Public domain, via Wikimedia Commons)
American biologist Nettie Marie Stevens. (© By The Incubator, courtesy of Carnegie Institution of Washington. Public domain, via Wikimedia Commons)

During her early adult life, Stevens had worked at Lebanon High School and Minot’s Corner School, teaching a range of subjects, including zoology, physiology, maths, English and Latin. Aged 35, she moved to California to study at Stanford University for a bachelor’s degree, majoring in physiology. She graduated at the top of her class and went on to study for a master’s and a PhD, and focused particularly on the science of sex determination.

Though Stevens was one of the first scientists to discover that sex is determined by the X chromosomes in sperm cells, credit for discovering the chromosomal basis for sex determination was given to fellow geneticist Edmund Beecher Wilson. Wilson had been conducting similar research independently at Columbia University.

Stevens is widely regarded as having expanded the field of embryology and genetics and earned her earned her PhD from Bryn Mawr College, Pennsylvania in 1903. She died of breast cancer on 4 May 1912.


Lise Meitner (1878–1968)

At the time Lise Meitner was growing up in Austria, girls weren’t typically educated beyond the age of 14. Born into a middle-class family, Meitner was privately educated so she could pursue her passion for physics. Her father, recognising her talent, employed private tutors to aid her academic development, and he also paid for private tutoring to help Lise prepare for the University of Vienna entrance exam, which she passed, choosing to major in physics for her undergraduate degree.

When she finally secured a research position at the University of Berlin in 1926, she was given a small basement room, with no salary, and wasn’t permitted to climb the stairs to the levels where the male scientists worked.

Austrian physicist Lise Meitner
Austrian physicist Lise Meitner (right), photographed c1953. Meitner was the first scientist to realise that an experiment had demonstrated the possibility of the nuclear fission of uranium. (Photo by ullstein bild via Getty Images)

After being forced to leave Berlin in 1938 due to her Jewish ancestry, as anti-Semitism rose in Nazi Germany, Meitner took a position in Stockholm at the Nobel Institute for Physics. From there, she continued to advise and correspond with her research team. When her colleague Otto Hahn relayed that his experiment had thrown up some unexpected results, it was Meitner who realised that his experiment was not ‘wrong’, but had demonstrated the possibility of the nuclear fission of uranium when it absorbed an extra neutron. Despite being a crucial member of this research team, Meitner failed to win the Nobel Prize in 1944 – it went to her former research partner Hahn.


Sarah Blaffer Hrdy (born 1946)

Sarah Blaffer Hrdy, a primatologist, anthropologist and emeritus professor at the University of California, is widely respected for her work into what primate behaviour can tell us about human evolution.

When Hrdy embarked on her career in the 1970s, it was accepted that human evolution had been shaped largely by male behaviour. Males were believed to be the ones under pressure to attract as many mates as possible in order to improve their odds of having more offspring. They were aggressive and competitive in their quest for dominance, and needed to be creative and intelligent when they hunted for meat. In contrast, females were believed to be passive, sexually coy and generally at the mercy of the stronger, larger males.

Things changed for Hrdy when she went out into the field for herself and saw how this account of females might be wrong. While studying the Hanuman langur monkey [a species of monkey widespread throughout south Asia], she witnessed male monkeys killing their own infants. She also witnessed how the female Hanuman langurs banded together and attempted to fight them off. This observation challenged long-standing ideas about natural primate behaviour, as it showed that females weren’t only fiercely protective of their children, but that they could also be aggressive and cooperative.

As a result of Hrdy’s research, it became impossible for primatologists to continue to ignore females. For her ground-breaking ideas on women, Hrdy has been described as the original Darwinian feminist.

Angela Saini is the author of Inferior: The True Power of Women and the Science that Shows it, published by 4th Estate and out in paperback on 8 March 2018.

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This article was first published by History Extra in March 2018