Susan Hockfield has many goals as MIT's new president, but the first she mentions is this: "I want to provide optimism and aspiration for people whose phenotype doesn't match the dominant phenotype." She's already fulfilled that ambition just by being herself, a distinguished neurobiologist whose last job was provost of Yale University. When her appointment was announced in August, Hockfield, 53, didn't think gender would be a big deal. After all, women run many prestigious universities, including Princeton, Brown and the University of Michigan. But it is still a very big deal when a woman presides over one of the world's most elite scientific institutions. Five years ago, MIT issued a highly publicized study describing bias against its female faculty members. Women are now about 17 percent of the faculty, compared with 11 percent in 1993. And MIT is not unique; at the nation's top research universities, women faculty remain scarce in science and engineering.

Against that background, Hockfield's rise is even more remarkable. The turning point was 1973, her senior year at the University of Rochester. A professor encouraged her idea for an experiment. "I said, 'What? Me? People like me don't do this thing.' And he said, 'No, you do it'." That led to a Ph.D. from Georgetown University and then to the Cold Spring Harbor Laboratory. Moving to Yale in 1985, Hockfield ran a lab researching brain development and became dean of the graduate school. She is married to neuro-oncologist Thomas Byrne; their daughter, Elizabeth, is 13.

Hockfield is not only the first woman but also the first life scientist to run MIT, and that distinction might matter most in the era of burgeoning interdisciplinary research. In 2004, MIT's research funding from the National Institutes of Health inched ahead of the Defense Department. As Hockfield gets ready to tackle the big questions, she's pondering the mundane. On campus a few days before she officially took office in December, Hockfield pointed out portraits of MIT's "first ladies." Will her husband be the first "first spouse"? Hockfield doesn't know... yet. It's another mystery waiting to be unlocked at MIT.