Few issues have divided the American public as bitterly as Charles Darwin’s theory of evolution by natural selection. Since On the Origin of Species was published in 1859, it has driven a wedge between those who accept that humans and this planet’s other inhabitants have evolved over time, and those who believe that our species was created in its current form with no alterations. While the majority of people in Europe and in many other parts of the world accept evolution, the United States lags behind. Today, 4 in 10 adults in America believe that humans have existed in our present form since the beginning of time, and in many religious groups, that number is even higher. This is woeful.

Now, at long last, there seems to be hope: National polls show that creationism is beginning to falter, and Americans are finally starting to move in favor of evolution. After decades of legal battles, resistance to science education, and a deeply rooted cultural divide, evolution may be poised to win out once and for all.

The people responsible for this shift are the young. According to a recent Pew Research Center report, 73 percent of American adults younger than 30 expressed some sort of belief in evolution, a jump from 61 percent in 2009, the first year in which the question was asked. The number who believed in purely secular evolution (that is, not directed by any divine power) jumped from 40 percent to a majority of 51 percent. In other words, if you ask a younger American how humans arose, you’re likely to get an answer that has nothing to do with God.

The increase in younger people embracing evolution is “quite striking,” says Kenneth R. Miller, a biologist at Brown University and an expert witness the landmark court case Kitzmiller v. Dover, which kicked “intelligent design” out of public school classrooms in 2005. “We’re moving in the right direction.”

It’s not just the young who are moving in favor of secular evolution. The overall proportion of Americans who believe in secular evolution has doubled since 1999, from 9 percent to 19 percent, according to a 2014 Gallup poll. But it’s important to note that the jump in secular evolution does not necessarily correspond to an increase in the total number who believe in evolution. Instead, most of that increase has been drawn from the pool of Americans who previously reported that they believed in evolution guided by God, which simultaneously dropped from 40 percent to 31 percent.

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Could these numbers be merely a blip—a stray mutation that will soon be weeded out of the population? Fortunately, there are several signs that these numbers do reflect a shifting cultural tide.

First, America is getting less religious. Today’s younger Americans no longer have the strong ties to organized religion that their parents did. About 56 million people now call themselves “nones” —meaning that they identify as atheist, agnostic, or nothing in particular on national surveys—a jump of 19 million since 2007, according to the 2014 Pew Research Center survey. Again, it’s the younger generation who are driving this shift: Fully 36 percent of young adults between 18 and 24 identify as nones, and the number of millennial adults who are religiously unaffiliated is growing fast.

That is not to say that religion doesn’t still exert a powerful hold on American identity; it does. However, the fact that fewer people are identifying with an organized religion is good news for science education, because many of those religions have historically opposed evolution.

Who are the people still perpetuating the view that evolution is a myth and that humans have existed basically as-is for the entirety of existence, which has lasted only about 10,000 years? By and large, they’re older Americans. About 34 percent of Americans 50 to 64 years old believe in creationism. For Americans older than 65, it’s 37 percent. From the perspective of people who endorse evolution, that’s a good thing—because, not to be insensitive, but old people die. When these elderly creationists shed their mortal coil, they will be replaced by that younger generation consisting increasingly of nones. The result: a steady phasing out of those who oppose evolution.

The gay rights movement had a word for this: generational momentum. “Which is a polite word for death,” says Evan Wolfson, the president and main architect behind Freedom to Marry. “That was our secret weapon: Old people die.”

Of course, old people dying wasn’t the only reason America finally made the historic decision this year to legalize same-sex marriage, Wolfson adds. To turn that cultural tide in such a short period of time, the supporters of gay marriage had to do something far more difficult: change deeply rooted attitudes and beliefs. Similarly, for the movement behind evolution to triumph, younger Americans who have been raised to believe in creationism need to be open to changing their minds. Fortunately, today’s generation is growing up in a time of greater open-mindedness and willingness to listen to evidence-based thinking, Wolfson says. Rather than being blinded by ideology, today’s young adults are open to evidence, facts, and reason. They want “information, not ideology.”

“Young people are growing up with a less ideological closed mind,” Wolfson told me. “Which is what a lot of the anti-evolution, anti–climate evolution, anti–climate change thinking is: It’s an ideology. It’s a refusal to engage with reality. Hopefully what we’re seeing here is that younger people are less prone to that. They’re allowing themselves to see the reality in front of them, as opposed to shutting their eyes on the basis of ideological denial. … They’re growing up in the midst of the conversation, growing up in the midst of reality, being open to reality, and not simply refusing to see what’s in front of you.”

There are many reasons for this shift. One is improving science education (more on that later). But another is that, in some ways, they don’t have a choice, argues Daniel Dennett, co-director of the Center for Cognitive Studies at Tufts University and co-author of Caught in the Pulpit: Leaving Belief Behind. He credits the rise of the Internet and the fact that today’s young people are more interconnected than ever before. “What is particularly corrosive to religion isn’t just the newly available information that can be unearthed by the curious,” Dennett wrote in April, in an op-ed entitled “Why the Future of Religion is Bleak” in the Wall Street Journal, “but the ambient knowledge that is shared by the general populace.”

For many Americans, evolution is in the cultural air we breathe. This year’s blockbuster Jurassic World takes as its premise the idea that birds evolved from dinosaurs. Or consider the television show The Big Bang Theory—which elevates science, including evolution, far above religion. In one memorable episode, Sheldon, a string theorist, flees back to his home and his religious mother in Texas after reaching a low point in his career. “This is my home now,” Sheldon tell his friends, who have followed him in an attempt to convince him to return. “Thanks to you, my career is over, and I’ll spend the rest of my life here in Texas—trying to teach evolution to creationists.”

His mother comes into the room. “You watch your mouth, Shelly,” she snaps. “Everyone’s entitled to their opinion.”

Sheldon: “Evolution isn’t an opinion, it’s fact.”

Mother: “And that is your opinion.”

Sheldon’s mother is laughed out of the room.

The message is clear: The fact-ness of evolution, at least to viewers of the show, is indisputable, and creationism is little more than a joke. Realizing the kind of nonsense he will have to deal with if he stays, Sheldon decides to return to his scientific career.

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Of course, evolution hasn’t won yet—not even close. Even today, plenty of powerful people are still promoting creationist nonsense, notably Louisiana Gov. Bobby Jindal, as Miller and Zack Kopplin have pointed out in Slate. Moreover, we can’t forget that a large bloc of young-Earth creationists still isn’t budging. Remember that 4 in 10 number? For those who attend church or synagogue at least weekly, that number is closer to 50 percent. For white evangelicals, it’s 60 percent. Those percentages haven’t budged in more than 30 years.

One of the greatest challenges to science literacy is the patchwork nature of the American educational system, says Josh Rosenau, programs and policy director at the National Center for Science Education. Despite the fact that the case law has been on the side of evolution and against creationism for decades, it’s impossible to know exactly what is going on inside the individual classroom. “That’s what makes our work so hard and so slow,” says Rosenau. “Even if a teacher isn’t teaching creationism, that doesn’t mean she’s adequately teaching evolution.”

“The biggest problem we’ve had is teachers who self-censor,” adds Eugenie Scott, co-founder of the NCSE and a former science teacher who has been part of the evolution versus creationism debate for more than two decades. “They’re responding to this very pervasive ‘There’s something wrong with evolution’ mentality. There are too many teachers around the country who anticipate that they’re going to get pushback if they teach the e-word, so they skip that section of the textbook. ‘Sorry kids, we don’t have time to cover everything—let’s go on to photosynthesis.’ ”

Scott is optimistic, but she’s also realistic. “We won’t have won until evolution gets taught as casually as we teach photosynthesis,” she says. “And we’re a long way from that.”

Wolfson agrees. Just because the trends show evolution’s supporters have the momentum doesn’t mean we can stop fighting, teaching, or speaking out. “This isn’t just some given that will drift along on its own,” says Wolfson. “It’s something to be nurtured and defended. We didn’t win the freedom to marry only because we had the momentum; we built that momentum. And we worked hard to harness it to the work of winning. The same goes for educating young people, promoting a scientific outlook and rational policy decision-making. None of it happens by itself. We still need to do the work.”

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The fight matters because we’re talking about the most fundamental tenet of modern biology. Origin of Species was just voted the most influential academic book of all time. As biologist Theodosius Dobzhansky wrote in 1973: “Nothing in biology makes sense except in the light of evolution.” Shared ancestry and adaptation by natural selection are what tie the biological sciences together, give them shape and meaning, and explain why life on Earth became the way it is. Trying to teach biology without evolution would be like trying to teach chemistry without the periodic table of elements: It just doesn’t work.

Moreover, evolutionary theory doesn’t exist in a vacuum. Beyond biology, evolution is supported by and makes sense of findings in geology, paleontology, isotope chemistry, biomedicine, and other fields. If we want to be a nation of politically and scientifically literate and informed people, then we have to teach good science—and that starts with evolution. “What makes the United States a world leader is our technology,” as Bill Nye (the Science Guy) said in a 2014 public debate with creationist Ken Ham. “If we continue to eschew science … we are not going to move forward, we will not embrace natural laws, we will not make discoveries, we will not invent.”

The trends reflected in the polls are good news. Let’s hope this means that Americans will embrace evolution regardless of their political and religious beliefs—even if the process of getting there feels as gradual as evolution itself.