When Caltech announced its fall 2024 incoming undergraduate class, the numbers told a story 133 years in the making: 113 women, 109 men. For the first time in the California Institute of Technology's history, women outnumbered men among new undergraduates. At an institution that didn't admit women as undergraduates until 1970 — and where women still represent a fraction of STEM graduates nationally — that shift is more than symbolic. It's a signal of how profoundly elite scientific education is changing, and why Caltech finds itself at the center of two converging conversations: one about who gets to do science, and one about whether the institutions that built modern science deserve to be celebrated without scrutiny of the people who built them.
A Historic Milestone 50 Years in the Making
The numbers are striking in context. Caltech's incoming class of fall 2024 became the first majority-female class in the school's 133-year history — arriving exactly half a century after the first women who enrolled as undergraduates graduated. Women were first admitted to Caltech as undergraduates in 1970, meaning that for more than a century, one of the world's premier scientific research institutions trained an almost entirely male student body.
That 50-year gap between first admission and majority representation is itself instructive. Admission and meaningful inclusion are not the same thing. Caltech's path from opening its doors to women in 1970 to achieving a majority-female class in 2024 reflects a broader truth about institutional change in STEM: it is incremental, uneven, and rarely as fast as the people inside these institutions would prefer to believe.
The milestone also comes against a national backdrop where gender parity in STEM remains elusive and highly dependent on the specific field. Women hold approximately 60% of degrees in biological sciences, according to the American Association of University Women — a field that has largely achieved parity or exceeded it. But women earn only about 18% of computer science degrees and roughly 20% of engineering degrees. Caltech, whose undergraduate curriculum is rooted in physics, engineering, and computer science, has historically reflected that disparity. Making the incoming class majority-female at a school with Caltech's specific disciplinary identity is a different kind of achievement than doing so at a liberal arts college or even a large public university.
What Caltech Actually Is — and Why That Matters
Caltech is not a typical research university. With roughly 1,000 undergraduates total, it is one of the smallest elite institutions in the United States — and one of the most research-intensive. The school has produced 47 Nobel laureates affiliated as alumni, faculty, or researchers. Its Jet Propulsion Laboratory operates as a federally funded research and development center managed by Caltech on behalf of NASA. When Caltech shifts its demographic composition, the ripple effects extend into the highest levels of scientific research.
The case of Katie Bouman illustrates what that means concretely. Bouman, an associate professor at Caltech, co-led a team of more than 300 researchers from 80 institutions to capture the first image of the supermassive black hole at the center of the Milky Way galaxy in 2022 — one of the most significant astronomical achievements in decades. Bouman's role became widely recognized after her earlier work on the first image of a black hole, in the galaxy M87, went viral in 2019. That a Caltech faculty member is among the most prominent scientists in the world speaks to the institution's influence. That Bouman is a woman in a field that remains heavily male-dominated makes her presence at Caltech — and Caltech's current trajectory — particularly meaningful.
The broader STEM ecosystem is beginning to invest more deliberately in this direction. ASML's recent $1.65M STEM grant reflects growing corporate and institutional recognition that the pipeline for scientific talent needs to be actively diversified to meet the demands of the next generation of research and technology.
Caltech in the Larger STEM Gender Parity Conversation
Caltech is not the first elite STEM institution to cross the majority-female threshold in its undergraduate class. Harvey Mudd College, another small, highly selective engineering and science school in Claremont, California, enrolled more women than men in 2010 and graduated more women than men in engineering in 2014. Harvey Mudd's transformation under then-president Maria Klawe became something of a case study in intentional institutional change: reforming how computer science is taught, emphasizing collaborative and creative applications over competitive gatekeeping, and actively recruiting women. The school demonstrated that the underrepresentation of women in STEM is not fixed by nature — it is shaped by how institutions recruit, teach, and signal belonging.
Caltech's path to majority-female enrollment has not been as publicly documented or credited to a single reform effort, which raises genuine questions. Was this the result of deliberate recruitment and curricular changes? Broader demographic shifts in who applies to elite STEM programs? A combination of both? The honest answer is probably that Caltech, like many institutions, benefited from decades of slow normalization alongside some targeted efforts — without a clear, auditable reform agenda driving it.
Nationally, the picture remains mixed. The AAUW data on computer science and engineering degrees shows that headline-level milestones at selective institutions don't automatically translate into sector-wide change. A majority-female incoming class at a 1,000-student school is meaningful as a signal, but the leaky pipeline problem — where women enter STEM fields at higher rates than they remain in them — persists well beyond undergraduate enrollment. Graduate programs, faculty hiring, and industry culture all contribute to attrition that enrollment figures alone cannot address.
The Shadow of Eugenics: Caltech's Uncomfortable History
The same year Caltech was celebrating its gender milestone, it was also grappling with a much more uncomfortable institutional history. Caltech's effort to confront its racist past centers on Robert A. Millikan, a Nobel Prize-winning physicist and the school's first president, whose name adorns one of Caltech's main libraries and multiple campus landmarks.
Millikan served as an officer of the Human Betterment Foundation, an organization that promoted forced sterilization and racial segregation — core tenets of the American eugenics movement. A petition signed by 1,083 Caltech community members called for removing Millikan's name from campus buildings, citing his active role in an organization that advocated for policies that caused direct, documented harm to thousands of people, disproportionately targeting people of color, immigrants, and disabled individuals.
The eugenics movement was not a fringe phenomenon in early 20th-century American academia — it was embraced by prominent scientists and university administrators who gave it institutional credibility and scientific-sounding cover. Millikan was not a passive bystander; he was an officer of an organization with an explicit ideological agenda. That distinction matters when evaluating whether his legacy on campus should be treated as neutral scientific history or as something that requires explicit moral reckoning.
The Naming Task Force and Its Fractures
Caltech's response to the pressure over Millikan's legacy was to establish a Naming Task Force tasked with examining policies around how campus buildings are named and renamed. It was a reasonable institutional response — deliberate, process-driven, aimed at broad community input. But the effort hit a significant obstacle in October 2020, when Sarah Sam, a doctoral student in neurobiology and the president of Caltech's Black Scientists and Engineers organization, resigned from the task force.
Sam's resignation was not quiet. She stated publicly that the Naming Task Force membership "neither has the background nor is willing to address institutional racism at Caltech." That is a pointed critique, and it cuts to a recurring problem with how institutions handle these conversations: assembling a committee becomes a substitute for action rather than a mechanism for it. When the people with the most at stake — in this case, Black students and scientists who bear the daily weight of studying in buildings named after eugenics advocates — conclude that the process isn't serious, that is not a procedural complaint. It is an indictment of institutional will.
The tension Sam identified is not unique to Caltech. Institutions that have built naming task forces, diversity committees, and equity offices in recent years have frequently faced the same critique: that these structures are designed to demonstrate responsiveness rather than produce accountability. Whether Caltech's task force ultimately recommended substantive changes to Millikan's campus legacy remains an unresolved question — one that the institution has not resolved with the same publicity it gave to its gender milestone announcement.
What This Means: Two Stories About the Same Institution
The juxtaposition of Caltech's headlines is instructive. On one hand, a genuine milestone: the first majority-female undergraduate class at one of the world's most selective scientific institutions, fifty years after women were first admitted. On the other hand, an unresolved reckoning with a founding figure who actively promoted the sterilization of people deemed racially or genetically unfit, and a task force that fractured under the weight of that reckoning.
These are not separate stories. They are both about who gets to belong to, and be honored by, one of the most powerful scientific institutions in the world. Gender parity in enrollment is a meaningful step toward broader inclusion. But inclusion that doesn't grapple with the institution's history of explicitly exclusionary ideology — including eugenics, which was never just an academic exercise but a system of state violence — is incomplete.
The practical implication for Caltech is that its reputation for scientific excellence increasingly depends on its ability to recruit and retain talent from the full spectrum of human diversity. That means not just counting women in the incoming class but ensuring that the culture, mentorship structures, and institutional symbols communicate that all scientists are genuinely welcome. Naming buildings after eugenics advocates is an institutional communication — and one that speaks louder than admissions statistics to the researchers who have to walk past those names every day.
For broader STEM education, Caltech's dual narrative is a useful corrective to the tendency to treat gender and race as separate equity conversations. Women in STEM are not a monolith; Black women in STEM face compounding barriers that enrollment milestones at predominantly white institutions don't automatically address. Progress on one axis of exclusion, while leaving others unaddressed, is progress — but it should be named accurately.
Frequently Asked Questions
When did Caltech first admit women as undergraduates?
Caltech admitted its first undergraduate women in 1970, more than 75 years after the institution was founded in 1891. The fall 2024 incoming class became the first majority-female class in the school's 133-year history, arriving 50 years after the first women who enrolled as undergraduates graduated.
Who is Katie Bouman and what is her connection to Caltech?
Katie Bouman is an associate professor at Caltech who co-led a team of more than 300 researchers from 80 institutions to capture the first image of the supermassive black hole at the center of the Milky Way galaxy in 2022. She became widely known after her earlier work contributed to the first-ever image of a black hole, in galaxy M87, released in 2019.
Why is Robert Millikan's legacy at Caltech controversial?
Robert Millikan, Caltech's first president and a Nobel Prize-winning physicist, served as an officer of the Human Betterment Foundation — an organization that actively promoted forced sterilization and racial segregation as part of the American eugenics movement. A petition signed by over 1,000 Caltech community members called for removing his name from campus buildings. Caltech formed a Naming Task Force to address the issue, but it was disrupted when a key member resigned, citing the task force's unwillingness to meaningfully address institutional racism.
How does Caltech's gender milestone compare to other STEM schools?
Harvey Mudd College, a similarly selective STEM institution, enrolled more women than men in 2010 and graduated more women than men in engineering in 2014 — making it an earlier benchmark for gender parity at elite STEM schools. Nationally, women earn about 60% of biological science degrees but only around 18% of computer science degrees and 20% of engineering degrees, according to the American Association of University Women, making parity at engineering-focused schools like Caltech particularly significant.
What happened to Caltech's Naming Task Force?
The Naming Task Force was established to examine Caltech's policies on naming campus buildings in response to community concerns about Robert Millikan's ties to the eugenics movement. In October 2020, doctoral student and Black Scientists and Engineers president Sarah Sam resigned from the task force, stating that its membership "neither has the background nor is willing to address institutional racism at Caltech." Her resignation raised significant questions about the seriousness and efficacy of the task force's mandate.
Looking Forward
Caltech's position in 2025 is that of an institution in genuine transition — one that is producing real milestones in scientific inclusion while still grappling with the weight of its own history. The majority-female incoming class is not a finish line; it is a data point in a longer story about whether elite scientific institutions can become genuinely representative of the society they claim to serve.
The test is not in the admissions numbers. It is in what happens to the women, the Black scientists, and the other historically underrepresented researchers who walk through Caltech's doors — whether they find mentorship, opportunity, and an institution that has reckoned honestly with who it was, as well as who it is trying to become. On both counts, Caltech still has work to do. The fact that it is increasingly visible on both fronts — celebrated for its milestones, scrutinized for its shortcomings — is itself a sign that the conversation has matured beyond what press releases can contain.
