At the time of her death in 1912, Nettie Maria Stevens was a biologist of enough repute to be eulogized in the journal Science by future Nobelist Thomas Hunt Morgan and for her passing to be noted in The New York Times. In 1910 she had been listed among 1,000 leading American “men of science.”
Yet in 1916, when Calvin Bridges published his proof that genes lie on chromosomes (the first paper in the first issue of GENETICS), Bridges cited the pioneering observations of a “Miss Stevens.” He also offered sincere thanks to “Dr. T.H. Morgan” and to his lab mates “Dr. A.H. Sturtevant and Dr. H.J. Muller.”
But “Miss Stevens” had in fact earned her PhD under Morgan’s supervision, just like Alfred Sturtevant, Hermann Muller, and Bridges himself. Why then did Bridges address the men as “Dr”, but granted Stevens only a “Miss”? The reason was likely convention. It seems to have been common in academic journals, including GENETICS, to refer to a woman with a PhD as “Miss” or “Mrs.” Indeed, Morgan’s obituary in Science is titled “The Scientific Work of Miss N.M. Stevens.”
In honor of Women’s History Month and the Centennial celebrations of GENETICS, Genes to Genomes takes a closer look at the “Miss Stevens” cited in the journal’s very first article.
Becoming a biologist
Before becoming a biologist, Stevens had been a teacher and occasional librarian for more than a decade. Her first career allowed her to save up for college; at the age of 35, she resigned from a high school teaching job in Massachusetts and traveled across the country to enroll at Stanford University in California.
At the time, Stanford was a five-year-old institution that was attracting many women interested in science majors. Stevens earned a baccalaureate degree, followed by a Master’s degree with research on the life cycle and microanatomy of ciliates. In 1900, the same year Mendel’s “laws of inheritance” were rediscovered, Stevens traveled back East to commence her PhD research at Bryn Mawr, a women’s college in Pennsylvania.
Stevens continued her ciliate work under embryologist and biology department head Morgan, who was impressed by her talent and independence (he was five years her junior). In 1901 Stevens was awarded a fellowship to study in Europe, where she worked with German zoologist Theodor Boveri. Around the time of Stevens’ visit, Boveri was conducting exciting experiments linking heredity to mysterious dark-staining entities in the cell nucleus known as chromosomes. Boveri’s work revealed that a complete set of chromosomes was needed for development to proceed normally, revealing that each chromosome maintained its own distinct identity.
Sex determination
After her European adventure, Stevens was eager to apply her impeccable histology skills to the hot topic of chromosomes and Mendelian inheritance. Once she graduated with her PhD in 1903, she and Morgan planned a collaboration on the controversial and unresolved question of how sex is determined in the developing egg. Did external factors, like food and temperature, set the sex of an egg? Or was it something inherent to the egg itself? Or was sex inherited as a Mendelian trait?
But by this time, Stevens was running out of savings. Without other means of support, she worried that her dreams of devoting herself to research would be buried in teaching duties. Morgan encouraged her to apply for a Carnegie Institution research fellowship and gave her an enthusiastic reference. Stevens was eventually awarded the fellowship and “freedom from anxiety over the money question.”
Part of the money was used for Stevens’ and Morgan’s collaborative work, in which they investigated the relation between sex determination and food source in aphids. But Stevens also pursued a side project on some alluring hints that sex was determined by inheritance of specific sets of chromosomes. In 1901, Clarence Erwin McClung had proposed that a peculiar chromosome in the insect Pyrrhocoris was responsible for determining its sex. At meiosis, this “accessory chromosome” was sorted into only one of the two sperm precursor cells.
Stevens examined a range of insect species in a hunt for other accessory chromosomes. When Stevens examined the meal worm Tenebrio melitor, she made a striking observation. This species produced two classes of sperm: a type that carried ten large chromosomes, and a type that carried nine large and one small chromosome. Body cells in the females contained 20 large chromosomes while males carried 19 large and one small chromosome. She reasoned that when an egg is fertilized by a sperm that carries the small chromosome, the result is a male offspring. The presence of the small chromosome might be what decided the individual’s “maleness.”
As is so often the case in science, one of Stevens’ colleagues discovered something similar at almost the same time. Prominent cell biologist Edmund Beecher Wilson made related observations of the behavior of an extra, unpaired chromosome in two hemipteran (bug) species.
But even combined with Wilson’s observations, it was not clear whether the pattern Stevens saw was just a quirk of an obscure species. The next important step, she concluded, was to examine a wider range of insects.
Stevens embarked on a painstaking survey that eventually covered 50 species of beetle and nine species of fly (including Drosophila melanogaster). Every species she examined had accessory chromosomes that either resembled Tenebrio (now known as an XY system) or they had an unpaired chromosome like Wilson’s bugs (now known as an X0 system). Clearly Tenebrio was no anomaly.
Sadly, Stevens never got to see final confirmation of her hypothesis. Though she continued pursuing evidence for several years, she died from breast cancer in 1912, at the age of 50.
Plate IV from Stevens (1905) showing hand-drawn micrographs from Tenebrio molitor samples.
American women of science
Morgan’s obituary for Stevens was ambivalent. He praised her “single-mindedness and devotion, combined with keen powers of observation; her thoughtfulness and patience, united to a well-balanced judgment.” Scientists had been slow to recognize the significance of her discovery, he said, because of their scientific conservatism. In almost the same breath, however, Morgan diminished Stevens by characterizing her as over-cautious and “at times wanting in that sort of inspiration that utilizes the plain fact of discovery for wider vision”. He portrayed her as a great technician but not a great theoretician.
Ironically, Morgan had been considerably more cautious than Stevens on the question of sex chromosomes. Indeed, his reference to “conservatism” in Stevens’ obituary may have been a subtle joke at his own expense, since he had only started to accept the evidence for sex chromosomes two years earlier. Some have also argued that Wilson was less willing than Stevens to embrace the Mendelian implications of the evidence. Either way, it would not be fair to characterize Stevens as over-cautious in her interpretations of sex chromosomes. The truth was, even though her observations were suggestive, she was right in concluding they fell short of proving that chromosomes determine sex. In 1908, she suggested the only hope of testing whether sex is indeed a Mendelian character must come from breeding experiments. Though she did not live to see it, she was correct. The matter was settled with Morgan’s own results mapping a Mendelian factor (the white eye mutation) to a sex chromosome in Drosophila.
In 1910, Stevens earned a coveted “star” next to her entry in “American Men of Science”, which meant she had been ranked among the top 1,000 scientists in the country. In a statistical analysis of this science elite, the directory’s publisher (who was also the editor of Science), noted that only 18 women ranked in the list, down from 19 women seven years earlier. He saw this as evidence that women were not as fit for the job as men:
“There are now nearly as many women as men who receive a college degree; they have on the average more leisure; there are four times as many women as men engaged in teaching. There does not appear to be any social prejudice against women engaging in scientific work, and it is difficult to avoid the conclusion that there is an innate sexual disqualification. Women seem not to have done appreciably better in this country than in other countries and periods in which their failure might be attributed to lack of opportunity. But it is possible that the lack of encouragement and sympathy is greater than appears on the surface, and that in the future women may be able to do their share for the advancement of science”
Today, the idea that women scientists in 1910 faced no social prejudice seems absurd. Nettie Stevens succeeded within a system that devalued her work. For example, the year she graduated from Stanford, the university’s co-founder Jane Stanford capped enrollment of women at 500 students, fearing her university was turning into a girls’ college. As a woman, Stevens could not have enrolled in graduate school at some of the most respected institutions in the country. Women were severely restricted in the types of academic jobs open to them. Women who did gain jobs in academia were expected (in some places legally compelled) to give up paid employment upon marriage.
Stevens lived in a world that assumed her inferiority and repeatedly emphasized that she was different from her male colleagues. Even in the dry pages of academic journals, her gender was appended, like an asterisk, to her name and accomplishments until long after her death.
Thanks to Casey Bergman for a Twitter conversation that prompted me to wonder about the use of “Miss Stevens” in Bridges’ 1916 paper.
Nettie Stevens’ microscope at Bryn Mawr College. This instrument was reserved for the use of advanced graduate students after Stevens’ death and was “much valued and treasured and affectionately known as the ‘Nettie Maria’.” (Ogilvie and Choquette 1981) Photo: Bryn Mawr College [CC BY-SA 3.0], via Wikimedia Commons
Cristy Gelling is a science writer, lapsed yeast geneticist, and former Communications Director at the GSA.
View all posts by Cristy Gelling »Read more in
-
Where are they now? Rosalind Franklin Young Investigator Award recipients share updates on their research
Rosalind Franklin Young Investigator Award applications are open–make sure you submit your application or nomination of a colleague by September 30, 2024.
-
University of Minnesota researchers map genome of the last living wild horse species
The study, published in G3: Genes|Genomes|Genetics, is part of larger conservation efforts to save Przewalski’s horse.
-
Congratulations to the Spring 2024 DeLill Nasser Awardees!
GSA is pleased to announce the recipients of the DeLill Nasser Award for Professional Development in Genetics for Spring 2024! Given twice a year to graduate students and postdoctoral researchers, DeLill Nasser Awards support attendance at meetings and laboratory courses. The award is named in honor of DeLill Nasser, a long-time GSA supporter and National Science Foundation…
-
Carolyn Damilola: an NFS Rising Scientist on a lifelong quest to learn more
Carolyn Damilola is an NFS Rising Scientist from Nigeria doing respiratory system research and paving the way for scientists from underrepresented communities through mentorship.
-
What does a good microgrant proposal look like?
Members of the Microgrant Review Committee share their tips for a successful proposal.
-
The first piece of the facial recognition puzzle
New research in GENETICS gives a first peek at the molecular pathway involved in recognizing faces.
-
New Senior Editor Amy MacQueen joins GENETICS
A new senior editor is joining GENETICS in the Genome Integrity and Transmission section. We’re excited to welcome Amy MacQueen to the editorial team.
-
Block party on the zebrafish sex chromosome
Research in G3 identifies a gene regulatory block of the zebrafish genome responsible for overseeing the maternal-to-zygotic-transition.
-
Unraveling the mysteries of duckweed: epigenetic insights from Spirodela polyrhiza
Research published in G3 offers insight into the impact of DNA methylation on clonal propagation in asexually reproducing plants.
-
A microbiologist’s quest to understand CRISPR in bacterial self-defense
2024 Genetics Society of America Medal recipient Luciano Marraffini determined how CRISPR-Cas systems destroy genetic targets with precision, paving the way for gene editing technology development.
-
Unlocking mysteries of trait and disease heritability in dogs
2024 Edward Novitski Prize recipient Elaine Ostrander, a pioneer of the domestic dog model, discovered numerous genes affecting dog size, morphology, behavior, and disease susceptibility—many of which have relevance in humans.
-
GSA and collaborators Personal Genetics Education & Dialogue and Reclaiming STEM Institute launch NSF-funded BIO-LEAPS project to support culture change in genetics
We are thrilled to announce that the Genetics Society of America (GSA) is collaborating with the Personal Genetics Education & Dialogue (PGED) based in the Department of Genetics at Harvard Medical School, and the Reclaiming STEM Institute (RSI) on a Leading Culture Change Through Professional Societies of Biology (BIO-LEAPS) grant from the U.S. National Science…
-
Daman Saluja: Navigating Science and Policy in India
In the Paths to Science Policy series, we talk to individuals who have a passion for science policy and are active in advocacy through their various roles and careers. The series aims to inform and guide early career scientists interested in science policy. This series is brought to you by the GSA Early Career Scientist…
-
A fly geneticist’s journey into discovering rules of organ development
2024 George W. Beadle Award recipient Deborah Andrew discovered new genes and pathways in Drosophila salivary gland organogenesis. Now, her work can help optimize cell secretion in therapeutic applications and fight malaria.
-
Małgorzata Gazda: How receiving the DeLill Nasser Award helped her land her dream job
Have you ever experienced an event that changes the course of your life, or in this case, your career? Małgorzata (Gosia) Gazda is Assistant Professor at the University of Montreal and in 2022, she received the DeLill Nasser Award for Professional Development in Genetics, which she used to attend and present at the 2022 Population,…
-
Hongyu Zhao joins GENETICS as new Senior Editor
A new senior editor is joining GENETICS in the Statistical Genetics and Genomics section. We’re excited to welcome Hongyu Zhao to the editorial team.
-
GSA Member Julio Molina Pineda Receives DeLill Nasser Award, Shines at TAGC 2024
“At any career stage, the GSA membership is an amazing investment for any genetics professional!” Julio Molina Pineda is a PhD Candidate in Cell and Molecular Biology and a Research Assistant at the University of Arkansas, and a Doctoral Academy Fellow at the Lewis Lab. In 2023, Julio was awarded the DeLill Nasser Award for…
-
In Memoriam: Ellsworth Herman Grell (1932–2023), a pioneer of Drosophila genome engineering and annotation
Ellsworth (Ed) Grell blessed the Drosophila community through three enduring legacies: as a pioneer of chromosome mechanics, as a primary organizer and synthesizer of genetic knowledge in Drosophila, and as a graceful mentor to those fortunate to have known him personally. Ed grew up in rural Nebraska, completed his undergraduate studies at Iowa State, and…
-
Congratulations to the #Fungal24 Poster Award winners!
We are pleased to announce the recipients of the GSA Poster Awards for posters presented at the 32nd Fungal Genetics Conference! Undergraduate and graduate student members of GSA were eligible for the awards, and a hard-working team of judges made the determinations. Congratulations to all! Felicia Ebot Ojong, The University of Georgia My research is focused…
-
Poster presentation tips for TAGC 2024
You’ve been selected to present a poster at The Allied Genetics Conference 2024 in March—you’ve celebrated, made plans to attend, now what? This is an exciting opportunity to showcase your research and engage with fellow members of the genetics community, so you want to make sure you’re prepared. We wanted to offer you some tips…
-
Maximize your TAGC 2024 experience
A guide to all that National Harbor & DC have to offer Are you joining us for The Allied Genetics Conference 2024 in March? Make the most of your #TAGC24 experience in National Harbor! We know the science will keep you busy, but you deserve to unwind and have some fun, so we’ve curated a…
-
Early Career Leadership Spotlight: Sarah Petrosky
We’re taking time to get to know the members of the GSA’s Early Career Scientist Committees. Join us to learn more about our early career scientist advocates. Sarah PetroskyMultimedia SubcommitteeUniversity of Pittsburgh Research Interest I am interested in understanding adaptation that has been happening recently in populations by dissecting the ways that genes underlying an adaptation…
-
TAGC 2024 Early Career Award Winners
GSA is pleased to announce the winners of the early career awards presented at The Allied Genetics Conference 2024. These awards are specific to particular TAGC communities and recognize early career scientists’ outstanding work on their respective research organisms. The awardees will present their talks in keynote sessions at TAGC 2024. Don’t miss the opportunity…
-
Preeminent geneticists recognized with revamped GSA Awards
In 2022, GSA’s Board of Directors launched an audit to review the five major awards conferred by the Society. Today, we are thrilled to announce the recipients of the reimagined GSA Awards, including the new Genetics Society of America Early Career Medal. The scientists honored this year are recognized by their peers for their outstanding…
-
Fly Board funds outreach programs to spread the word about Drosophila research
In 2020, the Fly Board voted to use part of its reserve fund to support efforts to increase trainee participation as well as equity and diversity in the Drosophila community. An awards committee decides how the money will be spent each year, and from 2020–2022, the committee posted a very broad call for applications from…
-
New members of the GSA Board of Directors: 2024–2026
We are pleased to announce the election of four new leaders to the GSA Board of Directors: 2024 Vice President/2025 President Brenda Andrews Professor, University of Toronto It’s an honor to continue my association with the Society by serving as Vice President of the Board of Directors. I have broad knowledge of the ongoing activities…
-
The Fly Meeting is one-of-a-kind! Dros 2025 organizers share their excitement
The 66th Annual Drosophila Research Conference promises to be a meeting rich with the latest in Drosophila research as well as opportunities to advance your career and connect with a global community of 1,400+ scientists. The organizers Todd Nystul, Michelle Bland, Leila Rieder, Amanda Crocker, and Justin Crocker are hard at work, planning a conference…
-
Early Career Leadership Spotlight: Olufemi Osonowo
We’re taking time to get to know the members of the GSA’s Early Career Scientist Committees. Join us to learn more about our early career scientist advocates. Olufemi Adekunle OsonowoCareer Development SubcommitteeDalhousie University Research Interest Metabolomics and genomics are two distinct but complimentary approaches that offer valuable insights into the underlying mechanisms of complex traits, such…
-
Early Career Leadership Spotlight: Hector Mendoza
We’re taking time to get to know the members of the GSA’s Early Career Scientist Committees. Join us to learn more about our early career scientist advocates. Hector MendozaCommunication and Outreach SubcommitteeUniversity of Michigan Research Interest My research goals converge around the evolution of sexual reproduction. During my doctoral program, I investigated mitochondrial inheritance, a mechanism…