The word “human” has a special resonance for McKernan these days. Although it’s always been a challenge to eke out a living as a visual artist — and the pandemic made it worse — McKernan now sees an existential threat from a medium that’s decidedly not human: artificial intelligence.

It’s been about a year since McKernan, who uses the pronoun they, began noticing online images eerily similar to their own distinctive style that were apparently generated by entering their name into an AI engine.

The Nashville-based McKernan, 37, who creates both fine art and digital illustrations, soon learned that companies were feeding artwork into AI systems used to “train” image generators — something that once sounded like a weird sci-fi movie but now threatens the livelihood of artists worldwide.

“People were tagging me on Twitter, and I would respond, ’Hey, this makes me uncomfortable. I didn’t give my consent for my name or work to be used this way,’” the artist said in a recent interview, their bright blue-green hair mirroring their artwork. “I even reached out to some of these companies to say ‘Hey, little artist here, I know you’re not thinking of me at all, but it would be really cool if you didn’t use my work like this.’ And, crickets, absolutely nothing.”

McKernan is now one of three artists who are seeking to protect their copyrights and careers by suing makers of AI tools that can generate new imagery on command.

The case awaits a decision from a San Francisco federal judge, who has voiced some doubt about whether AI companies are infringing on copyrights when they analyze billions of images and spit out something different.

“We’re David against Goliath here,” McKernan says. “At the end of the day, someone’s profiting from my work. I had rent due yesterday, and I’m $200 short. That’s how desperate things are right now. And it just doesn’t feel right.”

The lawsuit may serve as an early bellwether of how hard it will be for all kinds of creators — Hollywood actors, novelists, musicians and computer programmers — to stop AI developers from profiting off what humans have made.

The case was filed in January by McKernan and fellow artists Karla Ortiz and Sarah Andersen, on behalf of others like them, against Stability AI, the London-based maker of text-to-image generator Stable Diffusion. The complaint also named another popular image-generator, Midjourney, and the online gallery DeviantArt.

The suit alleges that the AI image-generators violate the rights of millions of artists by ingesting huge troves of digital images and then producing derivative works that compete against the originals.

The artists say they are not inherently opposed to AI, but they don’t want to be exploited by it. They are seeking class-action damages and a court order to stop companies from exploiting artistic works without consent.

Stability AI declined to comment. In a court filing, the company said it creates “entirely new and unique images” using simple word prompts, and that its images don’t or rarely resemble the images in the training data.

“Stability AI enables creation; it is not a copyright infringer,” it said.

Midjourney and DeviantArt didn’t return emailed requests for comment.

Much of the sudden proliferation of image-generators can be traced to a single, enormous research database, known as the Large-scale Artificial Intelligence Open Network, or LAION, run by a schoolteacher in Hamburg, Germany.

The teacher, Christoph Schuhmann, said he has no regrets about the nonprofit project, which is not a defendant in the lawsuit and has largely escaped copyright challenges by creating an index of links to publicly accessible images without storing them. But the educator said he understands why artists are concerned.

“In a few years, everyone can generate anything — video, images, text. Anything that you can describe, you can generate it in such a way that no human can tell the difference between AI-generated content and professional human-generated content,” Schuhmann said in an interview.

The idea that such a development is inevitable — that it is, essentially, the future — was at the heart of a U.S. Senate hearing in July in which Ben Brooks, head of public policy for Stability AI, acknowledged that artists are not paid for their images.

“There is no arrangement in place,” Brooks said, at which point Hawaii Democratic Sen. Mazie Hirono asked Ortiz whether she had ever been compensated by AI makers.

“I have never been asked. I have never been credited. I have never been compensated one penny, and that’s for the use of almost the entirety of my work, both personal and commercial, senator,” she replied.

You could hear the fury in the voice of Ortiz, also 37, of San Francisco, a concept artist and illustrator in the entertainment industry. Her work has been used in movies including “Guardians of the Galaxy Vol. 3,” “Loki,” “Rogue One: A Star Wars Story,” “Jurassic World” and “Doctor Strange” She was responsible for the design of Doctor Strange’s costume.

“We’re kind of the blue-collar workers within the art world,” Ortiz said in an interview. “We provide visuals for movies or games. We’re the first people to take a stab at, what does a visual look like? And that provides a blueprint for the rest of the production.”

But it’s easy to see how AI-generated images can compete, Ortiz says. And it’s not merely a hypothetical possibility. She said she has personally been part of several productions that have used AI imagery.

“It’s overnight an almost billion-dollar industry. They just took our work, and suddenly we’re seeing our names being used thousands of times, even hundreds of thousands of times.”

In at least a temporary win for human artists, another federal judge in August upheld a decision by the U.S. Copyright Office to deny someone’s attempt to copyright an AI-generated artwork.

Ortiz fears that artists will soon be deemed too expensive. Why, she asks, would employers pay artists’ salaries if they can buy “a subscription for a month for $30″ and generate anything?

And if the technology is this good now, what will it be like in a few years?

“My fear is that our industry will be diminished to such a point that very few of us can make a living,” Ortiz says, anticipating that artists will be tasked with simply editing AI-generated images, rather than creating. “The fun parts of my job, the things that make artists live and breathe — all of that is outsourced to a machine.”

McKernan, too, fears what is yet to come: “Will I even have work a year from now?”

For now, both artists are throwing themselves into the legal fight — a fight that centers on preserving what makes people human, says McKernan, whose Instagram profile reads: “Advocating for human artists.”

“I mean, that’s what makes me want to be alive,” says the artist, referring to the process of artistic creation. The battle is worth fighting “because that’s what being human is to me.”