When it’s hard to feel hopeful about the future of our country, we often fall back on hope about future generations. In the days after Donald Trump was elected, a map circulated on Twitter with the caption, “This is how the future voted,” purporting to show how millennials had cast their support on polling day. Forty-two of fifty states were blue. Among those sharing the image were feminists relieved that, for young people at least, there’s no question that a woman could be president—that in a new crop of hearts and minds, today’s lost battles had actually been won. But the map turned out to be merely a projection, published by a SurveyMonkey in late October. (The majority of young voters went for Hillary Clinton, but not in the numbers the map suggests.) And the expectation that each successive generation will be more gender egalitarian than the one before it might be an equally flawed presumption, according to new research published Friday by the Council on Contemporary Families at the University of Texas-Austin.

Since the mid-1970s, the University of Michigan has collected data about the attitudes of American teenagers and young adults. Over the years, respondents have increasingly shown support for equality between women and men. The 76 percent of high school seniors who believed that “a woman should have exactly the same job opportunities as a man” in 1976 became 89 percent by 1994, for example; the 75 percent who concurred that “a preschool child is likely to suffer if the mother works” fell to roughly half of respondents in the same period of time. But sociologists Joanna R. Pepin and David A. Cotter found “a surprising twist” when they revisited the data recently: Though on some questions “the answers have indeed continued to become more egalitarian,” they write, “on others, what had been a trend toward equality stopped or even reversed in the mid-1990s.”

High school seniors, the age group Pepin and Cotter chose to study, have continued to distance themselves from traditional attitudes in many respects—growing increasingly comfortable with working moms, for example, and with women executives and politicians. But in answer to one important set of questions, the respondents from 2014 were less egalitarian than their mid-90s counterparts: They were more likely to believe that, in a heterosexual marriage, the husband, not the wife, should be the ultimate authority and primary breadwinner.

In 1976, less than 30 percent of high school seniors disagreed with the statement that “it is usually better for everyone involved if the man is the achiever outside the home and the woman takes care of the home and family.” The map of teen attitudes and flipped almost completely by 1994, when 58 percent of high school seniors rejected the same assertion. As Pepin and Cotter write, “By 2014, however, it had fallen back to 42 percent—a decline of 16 percentage points since its peak in 1994.” Millennial teens are also split over whether “the husband should make all the important decisions in the family,” with 63 percent disagreeing, as opposed to 71 percent in 1994 and 59 percent in 1976.

When Stephanie Coontz, director of research at CCF and a professor at the Evergreen State College, saw Pepin and Cotter’s research, she was surprised, she told me—and she sent the findings to a number of experts to see how they might explain the shift. In one of the resulting papers, CCF research intern Nika Fate-Dixon broadens Pepin and Cotter’s inquiry from high school seniors to all 18- to 25-year-olds and finds a similar slippage in attitudes, suggesting that “the high school seniors… don’t simply represent a blip on the historical radar.”

In general, women give more egalitarian answers than men, and black respondents have more egalitarian leanings than white ones. Pepin and Cotter observed that, in their sample, all of these groups seemed to have grown more conservative to a parallel degree. Fate-Dixon’s research, however, found that the retrenchment of traditional ideas about gender was much starker among young men than it was among women. In response to survey questions about the ideal division of roles and power within a family, she writes, young men “went from 83 percent disagreeing in 1994 to only 55 percent disagreeing in 2014, a drop of 28 points in over the past 20 years.” Young women started in almost the same place (85 percent disagreeing) but changed by less—in 2014, 72 percent disagreed with the idea that men should be the primary breadwinners and women the primary homemakers.

“In fact, as of 2014, men aged 18 to 25 were more likely than their older counterparts to agree with the ‘old-fashioned’ notion that it is better for women to take care of the home and for men to be the achievers in the outside world,” Fate-Dixon points out. “In the 2014 survey, 67 percent of American men older than age 25 rejected the claim that the male breadwinner marriage is the ideal family form. But only 55 percent of men aged to 18-25 did so.”

Why would young Americans aspire to a model of marriage that many of their parents sought to remake? Coontz’s colleagues propose a range of possible answers. University of Utah professor Dan Carlson blames the lack of supportive policy in the U.S.—which, he suggests, may have caused many experiments in egalitarian family structure to fail. “Some youths who saw their parents experiencing disagreements and stresses as they tried to integrate work and family without supportive policies may have concluded that a male-breadwinner arrangement would have made family life easier,” he posits. Political scientist Dan Cassino suggests that some men are anxious to protect what’s left of the social capital masculinity once conferred. (In a previous study, for example, he found that men who earned less money than their wives did less housework than men whose earnings were on par to or greater.) According to his research, this impulse isn’t uniform: Conservative men who lose large amounts of income relative to their high-earning wives tend to grow more traditional in their views, while liberal men, placed in the same situation, grow polarized in the other direction, embracing egalitarian views.

It’s too early to explain how some millennials could support feminist policies in the workplace and a “father knows best” policy in their own homes. But it’s not hard to imagine how these personal feelings could leak into the political sphere—or, quite likely, how they already have. In the run-up to November’s election, Cassino ran a survey in which he asked men how their incomes stacked up against their spouses’, to see if thinking about “potential threats to their gender roles” had the power to affect their vote. As far as he could tell, the answer was yes. Most men who hadn’t been “primed” with that question told the researchers that they preferred Clinton. Most men who had said they were inclined to vote for Trump.