When former Harvard president Lawrence Summers caused a firestorm last year by suggesting that women are less innately talented in science than men, Barres called it verbal violence and felt he had to speak up.
"If people treat women as if they are less good, that treatment in itself causes them to be less confident, to choose to leave science," Barres said, adding, "I am always amazed when Larry Summers and others make this comment, because it so flies in the face of the data. A little bit less arrogance would go a long way."
In an impassioned response just published in the journal Nature, Barres references a slew of academic studies that found that women who applied for grants had to do more than twice as much work as men did, and that women at MIT were not getting equal resources, such as lab space.
His point: The gender gap in science has less to do with subtle differences in brain power and much more to do with bias.
Last week, a panel convened by the National Academy of Sciences said women in science and engineering are hindered not by lack of ability but by bias and "outmoded institutional structures."
The report recommends altering procedures for hiring and evaluating scientists, changing typical timetables for tenure and promotion, and providing more support for working parents.
Barres helps to fight bias by lending his hand to the respected Pioneer Award program, the National Institutes of Health's most prestigious prize. As a judge, he worked to make the application process more open, which led to important results.
Barres said the number of women and minority winners shot up from zero percent to nearly 40 percent. "The very best part was that we only discussed who was the best scientist and what was the best science."
And in Barres' perfect world, that's all that should matter.