Emma Hallberg’s Instagram is filled with pictures of her glowing brown skin, thick ebony curls and noticeably glossy pout. It was a shock, then, for one follower to discover that Hallberg is actually white.

It’s one case of what Twitter users call “blackfishing” — the phenomena of white female influencers pretending to be black through a combination of makeup and traditionally black hairstyles and fashion.

“On social media, they’re curating a performance of themselves that’s reliant on appropriating parts of black culture,” said Alisha Gaines, an associate professor of English at Florida State University and author of “Black for a Day: Fantasies of Race and Empathy.”

The term “blackfishing” became popular after a Twitter thread by the write Wanna Thompson went viral last year after she called out “all of the white girls cosplaying as black women on Instagram.”

“Let’s air them out because this is ALARMING,” Thompson said.

Photos of influencers poured in, many of them juxtaposing older photos with more recent ones showing women with visibly darker skin.

Long before Thompson’s post, racial impersonation had been normalized by the Kardashians, noted Jessamyn Stanley, a black Instagram influencer. Their signature look is constructed of phenotypically black beauty — accentuated lips and prominent curves. They also sport traditionally black hairstyles like box braids, cornrows or laid edges.

“How popular the Kardashians are speaks volumes and can’t be overlooked,” said Ericka Hart, a black Instagram influencer and sexuality educator. “They have been able to capitalize off black bodies, and people will want to emulate that.”

Kim and Khloe Kardashian have a net worth of $350 million, and the youngest of the Kardashian-Jenner family, Kylie, has been named the world’s youngest billionaire by Forbes.

The women featured in Thompson’s seemingly endless Twitter thread might not be as well-known as the Kardashians, but they also profit from brand endorsements and collaborations, Gaines said.

“They put themselves out there and have all of these followers thinking they’re someone that they’re not,” Gaines said. “It’s so deeply rooted in white privilege because they can take up a space that an actual black woman could have had.”

The products and promotions women like Hallberg receive from social media should be going to actual black women, Hart laments.

“They use black aesthetic like it’s a costume,” said Hart, who is also an adjunct professor at Colombia School of Social Work. “If you’re not black, you shouldn’t be doing that.”

Hart told NBC News that this trend is anything but new. From blackface minstrel shows to the freak-show attraction in 19th century London of Sarah Baartman, a South African woman, “there’s always been an inclination to take from black bodies,” Hart said.

While the indelible history of blackface in America has contributed to the modern phenomena of blackfishing, Gaines said there is a distinctive difference between the two. Blackface was intended to degrade and humiliate. These influencers instead practice racial impersonation and cultural appropriation, according to Gaines.

“People were able to contort their body landscapes into the way that black women look, and take what they think are the most beautiful parts and not respect the full black woman,” Gaines said.

The “beauty aesthetic” seen with blackfishing is what Stanley calls the Barbie version of black identity. It doesn’t include dark skin, kinky hair or full waistlines, she commented.

NBC News requested interviews with seven influencers accused of blackfishing; none responded.

Hallberg did, and she disputed accusations of blackfishing by posting photos on Instagram comparing her tan to other family members and from childhood showing her with natural curls.

“I do not get sponsorships, work opportunities and collaborations because of the color of my skin,” one of the posts reads. “I get it because of the way I style my clothes and create my makeup looks.”

Gaines called that a cop-out. “It’s a really flimsy excuse to me,” she said.

“You gain a lot of followers from people who think you’re somebody who you’re not,” Hart said. “People look up to you in a myriad of ways you might not even realize, and you’ve just been lying to them.”