Pretty much any animal medical researchers test is male. So too are the tissues they use to conduct tests. Despite the loads of research demonstrating important biological differences between how men and women react to various drugs or diseases, the default study subject is male.

That trend’s about to change, as the world’s largest medical funding agency — the US National Institutes of Health — announced today that it would grant a total of $10 million to 80 researchers who will study the effects of gender in their work.

To "overcome historical gaps in our knowledge of female biology"

"These awards are investments in science, helping us go deeper, and enabling a transformative shift that can overcome historical gaps in our knowledge of female biology," said Janine Clayton, NIH’s associate director for research on women’s health. They’re also the first step in a funding policy change that will soon force researchers to consider sex differences at the non-human, preclinical research stage if they wish to obtain federal grants.

One such instance is traumatic brain injury — women tend to recover faster than men. For some reason, women’s brains seem to have a protective benefit that researchers don’t understand. So "imagine if we knew more," Clayton said, "and could take lessons learned from the female brain to help men and boys recover faster." Another example is heart attacks. Women show different symptoms than men, and these are often dismissed by physicians. If we could study this more closely, Clayton says, then perhaps we could develop "clinical decision support software [for] emergency rooms that took sex into account."

There are many reasons for the current gap in our knowledge of female biology. Historically, scientists have been men, who have largely studied themselves. That, combined with the (incorrect) idea that hormonal changes in female animals could destroy statistically significant results, made for extremely male-centered research. And even though many researchers today acknowledge that sex differences are worth investigating, paltry funding has slowed efforts to understand them.

Historically, scientists have been men, who have largely studied themselves

"The larger the variability with each group, the greater the sample size needed to detect differences," said Brian Stauffer, a vascular biologist at the University of Colorado and one of the grantees, in an email to The Verge. So "the bottom line is large group size means more expense."

Stauffer himself had fallen victim to this kind of budgetary constraint. His study, which began in 2013, is aimed at investigating the differences between heart failure in children and adults. Because of initial budgetary constraints, though, his research team was unable to include enough tissue samples to properly examine sex differences. Now, with the NIH’s grant, the researchers will increase the number of children in the study, which Stauffer says will allow them to "understand some of the unique aspect of heart failure in boys versus girls."

Changes among scientists will be gradual. But today’s announcement is meant to alert medical researchers that these changes are, indeed, coming. Details about the policy and implementation plans will roll out gradually over the course of the next year, and the NIH will take the time to consider scientists’ concerns. But "in the long term," Clayton said, "we want scientists to consider sex from the start."