“By far,” he wrote, “the main difference that I have noticed is that people who don’t know I am transgendered treat me with much more respect: I can even complete a whole sentence without being interrupted by a man.”
Dr. Barres (pronounced BARE-ess) was born on Sept. 13, 1954, in West Orange, N.J., with the given name Barbara.
“I knew from a very young age — 5 or 6 — that I wanted to be a scientist, that there was something fun about it and I would enjoy doing it,” he told The New York Times in 2006. “I decided I would go to M.I.T. when I was 12 or 13.”
Barbara did indeed go to the Massachusetts Institute of Technology on a scholarship, graduating in 1976 with a degree in life science, then moving on to Dartmouth Medical School and receiving an M.D. there in 1979.
Dr. Barres became interested in the degeneration of brain function during an internship and residency at Cornell and returned to school to study it, this time at Harvard Medical School, receiving a Ph.D in neurobiology there in 1990.
A postdoctoral fellowship took Dr. Barres to University College London and the lab of Dr. Martin Raff, who was studying glia, the cells in the human brain that are not nerve cells. Dr. Barres went to Stanford in 1993, taking his interest in glia with him. In 2008 he became chairman of the neurobiology department.
“Ben pioneered the idea that glia play a central role in sculpting the wiring diagram of our brain and are integral for maintaining circuit function throughout our lives,” said Thomas Clandinin, a professor of neurobiology at Stanford who assumed the chairmanship in April 2016 when Dr. Barres’s cancer was diagnosed. “People had thought glia were mere passive participants in maintaining neural function. Ben’s own work and that of his trainees transformed this view entirely.”
Dr. Barres and researchers working with him studied the three types of glial cells and their role in proper neonatal brain development, as well as the possibility that inflamed glia are a cause of neurodegenerative disorders. Stanford said Dr. Barres published 167 peer-reviewed papers in his career.
To many, though, just as important as his research was his willingness to speak out on sexism and related issues. He called for more day-care support for women in the sciences who also wanted families. He criticized tenure systems that seemed weighted against women. He was furious at male colleagues who bragged about having sex with their female students.
But he also faulted women for being part of some of these problems — particularly women who succeeded despite the obstacles and then acted to protect their hard-won turf.
“Accomplished women who manage to make it to the top may ‘pull up the ladder behind them,’ ” he wrote in the Nature article, “perversely believing that if other women are less successful, then one’s own success seems even greater.”
His objections to the innate-differences arguments brought him criticism, with some arguing that he was trying to stifle unfashionable ideas in a way contrary to the academic tradition of open discussion. He disagreed sharply.
“When faculty tell their students that they are innately inferior based on race, religion, gender or sexual orientation,” he wrote, “they are crossing a line that should not be crossed — the line that divides free speech from verbal violence.”
He did not disagree that there are differences between male and female brains, but did object to the interpretation.
“People are still arguing over whether there are cognitive differences between men and women,” he told The Times. “If they exist, it’s not clear they are innate, and if they are innate, it’s not clear they are relevant.”
Or, as he put it in a 2015 letter to The Times prompted by an article about Caitlyn Jenner, “The question is not whether male or female brains are different, but why society insists on labeling male brains as better.”
Stanford did not have information on Dr. Barres’s survivors.
To convey that the playing field is often not level for women pursuing careers in math and science, Dr. Barres would sometimes recount an incident from his college days, when he was still Barbara.
“An M.I.T. professor accused me of cheating on this test,” he told The Times. “I was the only one in the class who solved a particular problem, and he said my boyfriend must have solved it for me. One, I did not have a boyfriend. And two, I solved it myself, goddamn it!”