As seen in "Nature"
Sir:
I was alarmed to learn in your Opinion article that President
Clinton's National Science and Technology Council was "toothless" in its
failure to address the shortage of women and minorities in science,
technology and engineering, and that this situation could have
"devastating" consequences by 2050 for the US economy and scientific
leadership.
An analysis of death notices and obituaries in Nature every 10 years from 1949 to 1999, and in Science every 10 years from 1949 to 1969 (after which it stopped regularly publishing these) suggests a way of increasing the number of women scientists dramatically. As I show here, women scientists rarely die. Once word of this acquired immortality gets out, women should flock to scientific careers.
Of 1,184 obituaries in a three-year period coded for year of publication, sex, age at death, cause of death (if known) and field, women accounted for 49 of 917 (5.3%) in Science and 13 of 267 (4.9%) in Nature; of the 44 commemorated in both journals, two were women. Science carried 3.43 times more obituaries than Nature; but the proportion of women remained constant at about 5% in each journal.
The dramatic increase in the number of women entering science, technology and engineering during the past 40 years (in which the number of female doctorates has grown at more than twice the rate of that for men, averaging 7.5% per year) coincided with acquisition of immortality in increasing numbers of these women.
Although women in the physical sciences were represented by 4.8% of the death notices in Science and 8.3% of the obituaries in Nature in 1969, by 1979 there were none - they had become immortal (see Fig. 1). Since women received only 2.2% of US doctorates in engineering by 1978, more time is needed to assess the degree, if any, to which women in this field have acquired immortality. Women in the life sciences started to become immortal in 1979, but immortality is not yet fixed in this group, since one obituary appeared in 1999 a year after women received 45.4% of the doctorates in that field (see Fig. 1). This trend is also found in other scientific and science-related fields of endeavour.
The fact that women were featured in some obituaries between 1949 and 1969 for all fields except engineering demonstrates that noteworthy women were contributing to scientific and scholarly endeavours half a century ago. As more females received doctorates over subsequent years, however, the numbers of obituaries for women decreased to zero in the physical sciences, social sciences, education, humanities and other categories. One may therefore conclude that women in these fields no longer die.
The big question, of course, is what are the factors that led to their immortality? Is there a gene that predisposes women scientists to live for ever? If so, I propose the name foy (fountain of youth), and suggest that the researchers at DREADCO look into this.
Dean Falk
Department of Anthropology, University at Albany, Albany, New York 12222, USA
Barbara McClintock was born in 1902 just before Mendel's work on genetics was rediscovered. She studied as an undergraduate in the College of Agriculture at Cornell University and when on at Cornell to study both cytology and genetics as a graduate. McClintock received her doctorate in 1927. McClintock's first major contribution was made as a graduate student. She learned to identify each of the 10 maize chromosomes. McClintock was exclusively or partially responsible for many of the contributions made to cytology and genetics by the talented Cornell maize genetics group, including the cytological proof of genetic crossing over. On fellowships, she spent time as an instructor at Cornell, the California Institute of Technology and the University of Missouri. As an assistant professor at the University of Missouri, McClintock began to study chromosomes that had been broken by X radiation. Later, she devised a method for using these chromosomes to generate new mutations. She continued her work at Carnegie Institution and in 1944, she was elected to the National Academy of sciences and in 1945, to the presidency of the Genetics Society of America. In 1983, she received an unshared Nobel Prize for her discovery of transposable elements thirty-five years earlier.
Marie Curie is the most famous woman of physics. She has been recognized for her work with Nobel Prize awards in both physics (1903) and chemistry (1911). She got a late start with her education obtaining her license in physics in 1893 and the corresponding degree in mathematics in 1894. In 1903, she finally received her doctorate. Choosing raioactivity as a thesis topic, Madame Curie examined a number of substances and found that thorium and its compounds behaved the same way as uranium. While examining pitchblende, a uranium ore, she discovered radium and polonium. In 1910 she succeeded in isolating pure radium metal. Marie Curie was also instrumental in setting up the Curie laboratory in Paris. She died in 1934 of leukemia, thought to have been brought on by her extensive exposure to the high levels of radiation involved in her studies.
Rosalind Franklin was a physical chemist who is best remembered for her contributions to the studies of coal, DNA, and plant viruses. She was born in London on July 25, 1920, the daughter of well-to-do Jewish parents. She received an excellent background in physics and chemistry at St. Paul's Girls' School and entered Cambridge University in 1938. At the age of 22, she gave up her fellowship to take her first position as a physical chemist at the British Coal Utilization Research Association. Between 1947 and 1950 she worked in a lab in Paris. It was there that she learned X-ray diffraction techniques, working closely with crystallographer Jacques Mering. In 1951, she left France for a three year research fellowship at King's College. Working with poor equipment, Franklin rigged a system for taking high-resoloution photographs of single fibers of DNA. In the autumn of 1956, Rosalind Franklin learned she had cancer, and on April 16, 1958 she died at the age of 37. Rosalind Franklin's crystallographic work gave experimental backing for the double helix model of DNA presented by Watson, Crick, and Wilkins. After her death, the three were awarded the Nobel Prize, giving no credit to Franklin for her invaluable work.
Sophie Germain was born in Paris on April1, 1776, the daughter of a well-to-do merchant. Having a library at home, she managed to find books and was able to teach herself Latin, Greek, and mathematics. Her education was limited by the male dominance of the period. Not allowed to attend school, she was forced to study the notes of other students and turn in reports under a male pseudonym. Lagrange read her reports, amazed by their quality, and upon discovering the author was a woman, sponsored her thereafter. She went on to do important work on Fermat's last theorem. She proved it for any prime number under 100 where specific conditions are met. She also mathematically modeled the vibrations of a flat plate. After having impressed Gauss, he arranged to have her awarded an honorary doctorate from Gottingen, but she died before it had been awarded. She died on September 17, 1851.
Obituary - Reprinted from Physics Today, May, 1995
Dorothy Crowfoot Hodgkin, sole winner of the 1964 Nobel Prize in Chemistry, died at her home in Ilmington, England, on 29 July 1994. She won the Nobel Prize "for her determination by x-ray techniques of the structures of biologically important molecules." The molecular structures that she determined include those of cholesteryl iodide, penicillin, vitamin Bl2, vitamin B12 coenzyme and the protein hormone insulin. Her achievements included not only these structure determinations and the scientific insight they provided but also the development of methods that made such structure determinations possible.
Dorothy Crowfoot, born on 12 May 1910 in Cairo, Egypt, obtained her first degree in chemistry at Somerville College, Oxford. Her x-ray crystallographic career started with her studies of thallium dialkyl halides with Herbert M. (Tiny) Powell in the department of mineralogy and crystallography at Oxford. She obtained a PhD at Cambridge University in 1937, working from 1932 to 1936 with John Desmond Bernal, who reinforced her lifelong interest in structural biochemistry.
In 1934 Bernal and Crowfoot first reported on the diffraction pattern of a protein crystal, pepsin, pointing out that protein crystals should not be dried but should be studied surrounded by their mother liquor (the standard method used since that time). The air-dried crystals gave very poor, if any, diffraction patterns, while those surrounded by mother liquor diffracted well.
Dorothy became interested in steroids while she was in Bernal's laboratory, and with Bernal and Isidor Fankuchen she studied crystals of over one hundred steroids and reported their unit-cell dimensions and the refractive indices with respect to these crystallographic axes. This monumental study of crystalline steroids showed, in the days before three-dimensional structure determinations, their probable crystal packing and hydrogen-bonding schemes.
Dorothy became a tutor and fellow of Somerville College in 1936. In 1937 she married Thomas Hodgkin, a tutor in adult education and a historian of Africa. She was made university lecturer and demonstrator in 1946, university reader in 1955 and Wolfson Research Professor of the Royal Society in 1960. One of her students was Margaret Roberts, later Margaret Thatcher, the only British prime minister with a degree in science.
With her student Harry Carlisle, she initiated a crystallographic study of cholesteryl iodide. Always on the lookout for new and better ways to solve structures, she pioneered the use of Patterson maps, using them to find the iodine positions; electron density maps using relative phases for the Bragg reflections based on these positions were then calculated. Dorothy had a particular ability to pick out a molecule from an electron density map with symmetry-related artifacts, such as were present in maps of the crystal structures of cholesteryl iodide and, later, penicillin. Cholesteryl iodide was one of the first analyses based on three-dimensional calculations, and it established the relative stereochemistry at each carbon atom of the steroids.
Dorothy's next big venture was the determination of the chemical formula of penicillin, which had been discovered in 1929. In 1944 Dorothy had some crystals of penicillin derivatives. The determination of the molecular structure of this compound was vital. A world war was in progress, and the best methods of production of penicillin to prevent wound infection were required. With Barbara Rogers-Low, Dorothy determined the structures of the sodium, potassium and rubidium derivatives of benzylpenicillin, using isomorphous replacement, optical analogs and difference maps. The molecule contained a four-membered ring of three carbon atoms and one nitrogen atom - this was the 13-lactam structure that had been assumed to be too unstable to exist independently. The chemical formula so determined served as the starting point for many chemical modifications that have been successfully used as antibiotics, such as the cephalosporins and thiosterpton, for which Dorothy also determined crystal structures.
In 1926 the fatal disease pernicious anemia had been found to be treatable by liver extracts, and in 1948 the active principal ingredient was isolated from liver in crystalline form as beautiful deep-red cobalt-containing crystals. E. Lester Smith brought them from Glaxo laboratories to Oxford so that Mary Porter and Reginald C. Spiller could determine if they were the same as those isolated by Karl Folkers at Merck Laboratories. Dorothy was excited at their appearance and immediately measured their unit-cell dimensions and molecular weight. She and her coworkers determined the structure and found that it was like that of a porphyrin ring with one bridging carbon atom missing so that two pyrrole rings were directly linked, and the B positions of these rings were each fully saturated. Dorothy used the cobalt atom to phase the hexacarboxylic acid derivative of vitamin Bl2, even though everyone advised her that it would not work because the scattering power of the cobalt atom was too weak with respect to the rest of the molecule. Later Galen Lenhert showed in her laboratory that the B12 coenzyme contains a cobalt-carbon bond, making this the first known naturally occurring organometallic compound. W. Lawrence Bragg, in Fifty Years of X-Ray Diffraction (Oosthoek's Uitgeversmaatschappij, Utrecht, The Netherlands, 1962), described the Bl2 study as "breaking the sound barrier," leading to new horizons in the field, namely the possibility of using heavy atoms to determine the structures of biological macromolecules, as had been suggested by J. Monteath Robertson in 1939. Since Dorothy's method worked for B12, people were encouraged to tackle the crystal structures of proteins.
Dorothy took the first x-ray diffraction photographs of insulin in 1935, and from then until the crystal structure was solved 34 years later, she was confident that the molecular structure could be determined from the x-ray diffraction pattern. The structure of 2Zn insulin was reported by Dorothy and her coworkers in August 1969. Chinese crystallographers, led by Tang You Chi, also worked on the crystal structure of insulin, and Dorothy traveled to China to compare the electron density maps of the two structure determinations. The diffraction patterns for insulin extended to very high resolution. After her retirement Dorothy, with Guy Dodson and his colleagues, published a definitive monograph on insulin.
Dorothy's influence on our understanding of biological structures has been unique, both through her firm belief that x-ray diffraction of crystals would give highly significant structural results and through her encouragement of young scientists who have gone on to expand the field themselves.
Obituary written by Jenny P. Glusker and Margaret J. Adams, Oriel College and Somerville College, Oxford, England
Sonya Kovalevksy was born in Moscow, the daughter of a Russian general. Being the daughter of an aristocrat, Sonya's intellectual growth was limited, as it was for many of the women throughout the 1800's. As a device to get away from parental supervision, Sonya married at eighteen and left for Germany. Under strict discrimination in Germany, she could not attend university lectures but her talent did not go unnoticed. She was taken in by Weierstrass to be tutored privately. In her work on differential equations she improved on the Cauchy. On the mathematical consideration of Saturn's rings, she improved on Laplace and Maxwell. She received a Ph.D. in absentia from Gottingen and was awarded prizes for here work of unusual merit. She was later elected to both the Swedish and Russian Academy of Sciences. She died of pneumonia, still in the height of her ability.
Maude Menten was one of the most versatile, innovative investigators in chemistry in the early part of the century. Born in 1879, she received her B.A. in 1904 and her M.D. in 1911 from the University of Toronto. She was a demonstrator of physiology in MacCallum's laboratory at the University of Toronto, a research fellow at the Rockefeller Institute, and a research fellow at Western Reserve University. While she was studying in Berlin with Michaelis, the Michaelis-Menten equation was developed. This equation gives an expression for the rate of an enzyme reaction and became fundamental to the interpretation of how an enzyme reacts on its substrate. Ultimately, Menten earned a Ph.D. in biochemistry at the University of Chicago. She later became a professor on the faculty of the University of Pittsburgh School of Medicine. In histochemistry, her publication in 1944 of a new technique for the demonstration of the enzyme alkaline phosphatase ushered in the new azo-dye method.
Ellen Henrietta Swallow was born in Massachusetts on December 3, 1842. At age 26, she entered Vassar College, having only four years of prior formal education, finishing the four year program in two years. She was admitted to study at the Massachusetts Institute of Technology "as an experiment" in January of 1871. By making her work indispensable, she avoided dismissal, working in a small basement laboratory. She became the first woman to be earn a bachelor of chemistry degree in America. After the isolation of a new metal, vanadium, Vassar awarded her an arts master degree. She was denied a request to study for a doctorate at MIT, which then promptly voted not to admit women. She remained an assistant to the men at MIT and began teaching science to female schoolteachers at night. In a renovated MIT garage, she opened the Science Laboratory for Women, the first of its kind in the world. It was here that she began her study of ecology which caused great controversy due to newly exposed environmental problems. In 1884, Richards became the nation's first female industrial chemist after the women's lab was closed at MIT. She lobbied the science hierarchy for a discipline which she called "Human Ecology." When this effort failed, she attempted to create a multidisciplinary profession by the same name. Melvill Dewey denied ecology a place in his classification system and the name was changed to "home economics." After having written her keynote address to the First World Congress on Technology, Ellen Swallow Richards died of heart disease on March 30, 1911.