The Dolan Twins, who have nearly 30 million combined followers on social media, are two of the most famous twin YouTubers.Frazer Harrison / Getty Images

You’re not imagining it: Influencers really are multiplying.

There are the Dolan Twins, a pair of square-jawed 19-year-olds who have amassed more than 10 million subscribers on YouTube and millions more on Instagram. They are joined by the Merrell Twins, the Rybka Twins, Niki and Gabi DeMartino, and Brooklyn and Bailey McKnight—massive YouTube stars, all. At this point, every up-and-coming YouTube star seems to have a body double, and every category of influencer has its own set of famous twins: twins who show off makeup techniques, twins who create exercise videos, twins who review toys. The popular YouTuber Jake Paul just welcomed a new set of twins, the Caci Twins, into Team 10, his YouTuber collective; they replaced the Martinez Twins and the Dobre Twins, who both left in 2017. Twin content is inescapable.

Last month, at the annual online-video convention Vidcon, an entire panel was devoted to teaching attendees how to create twin-related content; in the audience, rows and rows of young twins sat like Noah’s animals, all hoping to learn how to get their names in the spotlight. “We started a year or two ago. When we started it wasn’t as much of a thing,” says Jayda Johnston, a 15-year-old who attended the event with her twin sister, Jayna. Together they form the Johnston Twins and have more than 635,000 subscribers on YouTube.

Twins—and our fascination with them—are, of course, not new. Certain religions worship twins. Scientists study them. The actors Tia and Tamera Mowry and Mary-Kate and Ashley Olsen co-starred in various TV and film projects in the ’90s and early 2000s, and more recently, Dylan and Cole Sprouse anchored Disney’s The Suite Life of Zack & Cody. But nowhere do twins dominate more than on the contemporary internet.

Part of this is sheer numbers: There are more twins today than at any other time in history. According to a report by the National Center for Health Statistics, the rate of twin births rose by 76 percent from 1980 to 2009, when about one in 30 babies born in the U.S. was a twin. Since then the rate has only risen. The products of America’s twin boom are now old enough to be posting to Instagram and YouTube, where they are met with open arms.

“Twins play into something the YouTube algorithm is favoring at the moment,” says Dan Weinstein, the co-founder and president of Studio71, an influencer-management company. “So they’re surfacing more than they used to.” Teenage twin-content enthusiasts told me they liked to dream about what they would do if they had grown up with a twin—a fantasy identical twinfluencers play into happily, tricking their teachers and playing pranks on parents. “Much of twin content plays on this idea of challenges,” Weinstein says, “which frankly have been on YouTube for a long time as a general trend, but it’s very, very easy to play into that subgenre as a twin.”

Twins also have built-in chemistry. “It’s the same reason why couples channels do well,” Alan Stokes, a 22-year-old influencer with 4.3 million followers on Instagram, told me. “Twins are the closest you can get to someone without it being a couple thing.” Alan’s twin, Alex (3.4 million followers), chimed in: “I’ve noticed on YouTube especially, pairs just work better. It makes the video more interesting.”

Having a twin also lowers the barrier to entry to becoming a creator. For influencers to grow online, collaboration is key. Being a twinfluencer means having someone around you to act as a sounding board, brainstorm with, or simply hold the camera. It also means splitting editing and promotion time between two people: While one twin responds to fans via Instagram DM, the other can cut together the day’s YouTube video. This allows each twin to play to their strengths, together acting as one super-influencer. “My sister, Olivia, is more organized than me,” says Ashley Mescia, a 19-year-old influencer. “I’m better when it comes to socializing.”

Meet and greets and brand events, too, are easier with a partner. “Whenever we meet new people, we’re not too shy because we feed off each other. We can fill in the spaces where the other one lacks,” says 18-year-old Myka Montoya, who is one half of the Montoya Twins.

Splitting everything isn’t always painless, however. Some twins said they were more likely to fight with a sibling than a friend. Others mentioned that when you’re a twinfluencer, you can’t have autonomy over your own channel or Instagram account. Maintaining a twin brand, especially as both parties develop their own unique personalities and interests, can be hard. While the Stokes twins maintain a shared YouTube channel, each has an individual Instagram account. “I didn’t want people to only see us as one person,” Alex says. On Instagram, they often match their outfits, though in real life they maintain different looks. But one twin won’t make a change in appearance without the other doing it too.

Everyday Mood 😜😈 #twingang

A post shared by Jake & Pete (@randalltwins) on

“A drawback being a twin is there’s two people. You have to share, you have to make sure you’re on the same page all the time, and you have to share attention,” says Jake Randall, a 23-year-old influencer. “People think we get along all the time, but when you live with someone 24/7 for 23 years, it doesn’t always go like that.”

Jake said that when conflict does arise, he and his brother, Pete, are quick to resolve it since they love each other. For instance, last year they were approached about an opportunity to be on a Facebook Watch show, but there was only one spot, so they had a basketball trick-shot contest. Jake won but ultimately gave the spot to Pete because he knew how badly he wanted it. Had they simply been collaborators and not brothers, things might have turned out differently.

Meredith Levine, a research consultant, told me that the twinfluencers of today are paving the way for even more twin content in the future. Hundreds of twin-related YouTube channels and Instagram accounts have sprung up in recent years. And smaller twinfluencers like the Herbert Twins, who have 165,000 subscribers, or the Mescia Twins, with 253,000 subscribers, are gaining traction. “You see an established model of [content] formats that twins can make that other sets of twins who arrive on the scene can replicate,” she said. “When you see other twins being able to do this, you have a generation of people growing up saying, ‘Oh, I can work with my twin, we can do this together instead of having separate 9-to-5 jobs.’”

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