Male and female students in an introductory biology class performed better when there were more women in their study group.

Three female students reading a book circa 1950. (Photo: Keystone View/FPG/Getty Images)

Introductory science classes tend to be tough. They are, after all, where college freshmen find out if they have the aptitude to major in one of the STEM fields. Often, a few low test scores is all they need to decide the answer is no.

This is a particular problem for women, who have already received hints from the culture that they are not inherently cut out for such work. But new research has uncovered a plan of action that can increase both their odds, and those of their male counterparts: They should gravitate toward female-dominated study groups.

"The inclusion of women may accomplish more than simply addressing gender diversity," writes a research team led by Lauren Sullivan of the University of Minnesota. "Female-majority groups had a significant, positive influence on student performance regardless of gender."

In the online journal PLoS One, the researchers describe an experiment featuring nearly 400 University of Minnesota undergraduates taking one of two introductory biology courses for non-biology majors. The class covered such basic principles of biology as evolution and genetics.

Throughout the entirety of the course the students were assigned to sit at a specific table, which sat eight to nine. For the larger class, "We designed each table to have a gender ratio of all women, women majority (75 percent), gender parity, women minority, or all-men," the researchers write. For the smaller one, the students were randomly assigned, but table gender ratios were noted.

Since these were "active learning classrooms," the students "had ample opportunity to interact with one another and develop perceptions of their peers, and their own performance in the group," the researchers write. At times, they were instructed to work together to solve problems.

Grades were determined by a combination of factors, including test scores, laboratory work, and "collaborative group work and in-class participation."

Sullivan and her colleagues found the gender of one's table-mates made a difference.

"As the percent of women in each group increased," they report, "student performance increased relative to the classroom mean, regardless of gender."

The researchers suspect the reasons for this boost may differ for male and female students.

"Women may benefit from being a numeric majority through the reduction of stereotype threat," they write (in this case, the stereotype being that women are less adept at science than men). "Women may require a critical mass of other women before a sufficient sense of belonging will positively influence performance."

As for men? The researchers discuss two hypotheses. "Improved group cohesion in female-dominated groups may have reduced barriers to discussion during the problem-solving sessions, which resulted in better understanding for all," they write.

Alternatively, men in such groups may have felt more comfortable being assertive and asking important questions than they would be in a male-dominated group. With alpha males elsewhere, the beta males could step up and reach their full potential.

These findings are even more interesting when paired with another new study, which asked 250 students in a university biology course to estimate their intelligence. It reports men were 3.2 times more likely than women to say they were smarter than the classmate they work with most closely.

It further found that, on average, a man with a 3.3 grade point average judged himself to be smarter than 66 percent of his classmates, while a woman with that same score estimated she's only smarter than 54 percent.

So, male STEM students, if you want to avoid crashing and burning because of overconfidence, find a group of women classmates, and start collaborating. When it comes to studying biology, it's not so much the frog you are dissecting as who you are dissecting it with.