In the past, female researchers were often dismissed as the 'brawn behind the brains' in teams of scientists, leaving men to take the credit, yet a few women managed to beat the odds to make their mark and achieve Nobel success.
Only ten women - compared with almost 500 men - have won Nobel prizes in science. The fact that Nobels are given almost exclusively to academic researchers means universities share responsibility for this remarkable disparity. In the early days of the Nobel, laws and parental opposition prevented many European women from entering universities. Marie Curie left Poland in 1891 to study in Paris because the Russian Empire prohibited women from Eastern Europe to the Pacific from studying at universities. Emmy Noether, whose mathematics laid the foundation for quantum theory, lectured under someone else's name in Germany until after the first world war.
As late as the 1920s, German education for women consisted primarily of finishing schools without the mathematics, science, Greek or Latin required for university entry. Physicist Lise Meitner, who explained fission in 1938, referred to the nine years she spent in finishing and normal schools in Austria as her "lost years": she believed they handicapped her for life.
Nobel prizewinning biologist Rita Levi-Montalcini was 21 years old in 1930 before she convinced her father to hire a tutor so she could begin academic studies in Italy. In England, near-winner Rosalind Franklin's father at first refused to pay her university expenses and ordered her home to do volunteer work during the second world war; Franklin persevered and eventually took the X-ray photographs of DNA that helped reveal its helical structure.
In the United States, women could get a university education - but no job. Until the 1970s, many leading research universities and technological institutes were only for men. To teach in women's colleges or in coeducational universities, American women were expected to stay single. Barbara McClintock, the Nobel prizewinning geneticist, was a few years from membership of the National Academy of Sciences when her boss at the University of Missouri threatened in 1936: "If you ever marry, you'll be fired." McClintock stomped out, planning to become a weather forecaster, until she found a job funded by the private Carnegie Institution of Washington at Cold Spring Harbor Laboratory.
So-called anti-nepotism rules - whether state laws or university regulations - were devastating for married female scientists well into the 1970s. Anti-nepotism provisions banned universities from hiring relatives of their employees. Universities made many exceptions for sons and brothers but few for wives, many of whom were married to other scientists.
Even today, almost 70 per cent of the married female physicists in the US have spouses who are scientists, and almost half are married to other physicists. Many American women solved the anti-nepotism problem by marrying a scientist and working in his laboratory or by forming a long-term "professional marriage" with a male researcher. Gerty Cori, a Czech-American, was her husband Carl's research associate for 13 years at one-fifth of his pay. She did not become a professor at Washington University in St Louis until 1947, the year she and her husband won the Nobel prize for explaining carbohydrate metabolism. Until recently, the academic landscape of America was dotted with such couples, especially in biology.
Because her husband was a chemistry professor, the 1963 Nobel physics winner Maria Goeppert-Mayer worked for more than 30 years at Johns Hopkins University, Columbia University and the University of Chicago as a "voluntary researcher" or "voluntary professor". Although the federal government paid for Mayer's government research, she was not paid for university teaching, research and committee work until ten years after she discovered the nuclear shell model. Worried that she was harming her husband's career, she behaved "very carefully" and let competitors publish their work first, a practice that almost cost her the Nobel prize. These anti-nepotism rules were not reformed until Congress passed the Equal Employment Opportunity Act of 1972 and extended its provisions to federally funded universities.
Collaborating with men has had advantages and disadvantages. On the positive side, it means that women are more used to the kind of teamwork now common in science. But in the past, men were generally regarded as the brains of the team and women as the brawn. Gertrude Elion shared the 1988 Nobel prize in medicine or physiology with her long-time collaborator George Hitchings for developing a scientific approach to drug discovery. At first, the Nobel committee doubted that Elion deserved the prize. Then university colleagues emphasised that she was first author on her early papers and that, after Hitchings retired, she discovered the first anti-viral drug on her own.
Today, many scientists believe that physicists Lise Meitner and Chien-Shiung Wu and astronomer Jocelyn Bell Burnell should have won Nobel prizes. Meitner's German research partner won for an experiment that Meitner started, led and explained; it demonstrated that atomic nuclei can break apart, releasing enormous amounts of energy. A Swedish physicist who clashed with Meitner, apparently blocked her prize. Wu's experiment showed that the law of parity can sometimes be violated, but those who proposed the theory, which her experiment proved, won the prize. Bell Burnell discovered pulsars, while her thesis adviser won the prize. However, the most famous non-winner - Rosalind Franklin - failed to get a Nobel because she died at the age of 37; Nobels are not given posthumously. Had she lived, she would surely have shared the 1962 prize for medicine or physiology for the discovery of the double helix. In the event, it was awarded to James Watson, Francis Crick and Maurice Wilkins.
Nevertheless, despite their problems, female scientists have actually won more Nobel prizes in proportion to their numbers than female writers. Only nine women have won a Nobel for literature, and no female economist has won a Nobel.
Although the condition of women in science has improved vastly, numerous studies have shown that female scientists still get fewer professorships, lower salaries and less grant money and work space than male peers. Subtle but widespread discrimination has been documented in studies ranging from the Massachusetts Institute of Technology to the Swedish Medical Research Council. In addition, the problem of scientists married to scientists - the "two-body problem", as physicists call it - remains a major impediment. The American Physical Society's Committee on the Status of Women in Physics has set up a website detailing some of the problems that face women scientists in the US as a result ( www.physics.wm.edu/dualcareer.html ).
Effective action is essential because universities are largely funded by taxpayers, half of whom are women. In addition, US universities are soon expected to replace large numbers of professors who were hired in the 1960s boom years and who now face retirement.
Past studies documenting discrimination show that positive action has had mixed results. For example, the number of tenured women at the University of Pennsylvania has barely changed since the 1980s, despite a class action suit in 1971. And when Harvard promoted several female scientists to full professor after a 1991 report, it did not replenish its pool of tenure-track women.
It is a cliché to note that scientific research in higher education puts pressure on women during their child-bearing and raising years. The fact remains, however, that institutionally there has been little real change to overcome this problem, which in the US is the result of a tenure system designed for young men married to housewives. Today, few professionals of either sex have housewives. The lack of quality day care is another pressing problem for many young academic couples, particularly in the US, Britain and Germany.
In France and Italy, where research scientists achieve tenure by the age of 30, many women are able to combine research and families. In Northern Europe and the US, however, career pressures placed on women during their 20s and 30s will probably not be moderated until enough women - and their partners - achieve positions of academic power.
Sharon Bertsch McGrayne
Sharon Bertsch McGrayne is the author of Nobel Prize Women in Science: Their Lives, Struggles, and Momentous Discoveries , published by Joseph Henry Press, £14.95, and Prometheans in the Lab: Chemistry and the Making of the Modern World , published by Schaum, £18.99.