Harvard president Lawrence Summers's recent suggestion that lower innate ability may explain women's conspicuously scant representation in the upper reaches of academic science made headlines around the world. But, according to early-career scientists who shared their views with Next Wave, the two less-publicized possibilities that Summers mentioned, motherhood and discrimination, are more plausible explanations.

"Top-level positions at American universities is still a boy's game," according to Maristela Martins de Campos, formerly a postdoc at Yale and currently an assistant professor and PI at the University of Sao Paulo, Brazil, where, "oddly enough ... the proportion of women PIs and other top-level positions is much higher" than in the U.S. In "very patriarchal" Brazil, she notes, the husband is "expected to be the family provider." Dismal academic incomes drive many men out of graduate training and early research positions, leaving numerous jobs for women who are "not expected to support a household."

When she worked in labs in Bavaria, Germany, on the other hand, there was "only one female PI in five large departments I circulated in," Martins de Campos reported. Women there told her that because the government did not encourage daycare, mothers had few affordable options. "I can't tell whether this was a national phenomenon," Martins de Campos observed, "but . . . women scientists I met there had a difficult time pursuing their careers."

The situation is different in America, where more early career scientists are involved in egalitarian, two-career marriages with professional opportunities for both spouses. The advent of offspring, however, often severely tests that ideal. "I don't think gender has much of an effect until children are involved," observed a postdoc and mother we'll call Stella Noptimist. "This is a fact of basic biology, not gender politics."

The Weight of Motherhood

"I lost so much time during the pregnancy and maternity leave, I felt like I would never catch up," Noptimist continued. Another, better established scientist, whom we'll call Mona Canmanage, says that motherhood will probably push her out of academe. Canmanage had her first child after winning independent grants as a postdoc, then another as a non-tenure-track faculty-level researcher. "No one was mean or rude," she reports, but several male superiors "just matter-of-factly" warned her that six weeks of maternity leave and occasional absences for her baby's routine minor illnesses have "hurt her chances" of grant renewal in today's brutally competitive funding environment. "There is no 40-hour work week" in academic research, Canmanage's superiors explained; 60 hours is the "acceptable minimum." Her scientist husband, who shares childrearing responsibilities and has also taken off time for family illness, has received no such admonitions.

Motherhood takes away something even more crucial to a research career than time at the bench, according to former postdoc Karen Forkids (not her real name). "Before the kids, I pondered molecular biology questions while relaxing in the shower," she recalls. "Now, post-kids, I ponder how to stop the bickering and how to feed and clothe them. Gone are the hours of solitude for thinking." Her changed priorities, plus an unwillingness to use full-time day care, led Forkids to "the slow track" of part-time laboratory work. Canmanage, similarly, is considering a government job with a less demanding and more predictable schedule.

Noptimist, however, resumed full-time lab work despite fearing that her hiatus would end her research career. In conversations with faculty members who had themselves given birth as postdocs, she learned that her doubts are "a perfectly normal phase the mothers go through," she gratefully recalls. "After you get used to your role as a mother, your productivity gets back on track and people in the academy are actually willing to cut you a break for a year of low productivity. But that period of time right around the birth of your first child is really, really hard," she notes, adding that she still hopes for "an academic faculty position once I get some more publications."

Dealing with Discrimination

Whether women like Noptimist can fulfill their ambitions appears to depend in part on how well they can overcome the "implicit bias against women" in academic science, says a male postdoc we'll call Kent Denyit. A believer in "intrinsic differences between men and women in scientific ability," he thinks that "if people would acknowledge that fact [of differences], we could discuss fair ways of dealing with it." But he also readily acknowledges that "many aspects of science departments are male-oriented" and disadvantage women "in a wide variety of ways."

The grossest forms of discrimination may have passed from fashion, but "academia changes slowly and the aftereffects of past discrimination last a long time," Denyit says. Phyllis Unfair--not her real name--sees those effects at the top university where she is currently doing her second postdoc. "There's no 'Men's Dining Room,'" she reports, but rather a "pervasive, low-level sexism that seems minor but has cumulative, disastrous effects on the women here."

Female scientists "were well-respected" and held "important positions of power" on the campus where she formerly worked as a postdoc. At her current university, however, she notices "unintentional and minor" ways in which "many of the male PIs seem to focus largely on the male postdocs. They chat with the men, brainstorm with the men, check in on the men's experiments, suggest their new ideas to the men. And lo and behold! The men's research goes better! It becomes self-fulfilling. A project started by a woman somehow ends up with a man as the first author of her paper. A woman whose research has gone well is still seen as unproductive by the PI who never talks to her. And I think it's simply because the male PIs feel more comfortable chatting with the male postdocs. They don't even recognize they are favoring them. But a couple of years of benign neglect from your PI can really undermine the research you are trying to do--and the confidence to push yourself out there to tell the world you deserve a job."

When such "small things ... produce a measurable, drastically different outcome," agrees the postdoc we'll call Candace B. Happening, "then they cannot be called small any longer." That her office is less comfortable and her computer less snazzy than her male counterparts' doesn't really affect her research, she believes. Far more damaging is her PI's tendency to ignore her, "not deliberately," but so obviously that her male colleagues "had to ask him to make an effort to include me." Even worse is the PI's "implicit assumption" that males do better science than females. When he assigns plum experiments with "a high potential for prestigious, interesting data," he chooses the person he considers "most capable; in his head, this is not a female."

Such bias leaves less-favored postdocs like Happening with the "daunting task" of devising an experiment that PIs "have not thought of, convincing these big shots ... to allow time for this experiment on the ... instrument, and finding funds to do it. Needless to say, the 'obvious' experiments have a much higher chances of success," she believes.

Coping with Competition

Though Unfair has encountered bias, she, like Denyit, recognizes that statistical differences exist "between male and female behavior that have biological" as well as cultural origins. In her opinion, though, they "reflect well on women. It's not really about men versus women. It's about people who are willing to sacrifice their entire personal lives to their career and those who are not." The genders have "broadly overlapping bell curves for 'workaholicness,'" she thinks. "But at the very extreme end," scientists "who work in the lab nonstop and have nothing else in their lives" are generally male. "These single-minded, friendless workaholics tend to succeed in the highly competitive environment of academia."

Women comfortable with the "competition, individualism, and the drive for power and glory" that characterize high-powered labs are "less common than men," agrees Denyit. But, he suggests, labs could be "modified to accommodate more women. Competition is obviously a good thing" in research, but if "the group was competing against other groups, rather than intra-group competition, I think more women would thrive."

"Hiring more women PIs would certainly help," says Unfair. And "women postdocs should learn to be more pushy when they have to be, bragging about their new data to the PI, protecting their territory in the lab like the men do." Beyond that, she thinks that institutions should insist on "better mentoring of postdocs . . . reminding PIs that they owe each postdoc their time and help, especially when things aren't going well."

And certainly institutions could profitably give more attention to the issue of bias because, as Denyit puts it, "changing cultures is difficult and slow." Until that happens, argues Martins de Campos, biological theories explaining differences in scientific achievement will "run on empty if ... conditions for both genders are not the same."

Beryl Lieff Benderly writes from Washington, D.C.