Not since a chorus of children began admonishing radio listeners to dial 1-877-Kars-4-Kids has a song burrowed into the public consciousness quite like “Baby Shark” (doo doo do doo doo do!). The tot-friendly tune about congenial sharks searching for a meal has racked up over 2 billion YouTube views to become one of the site's top-viewed videos of all time. It also shows no signs of abating anytime soon: Netflix plans on streaming a series of shorts that will flesh out the carnivorous adventures of the title character. In December, Baby Shark toys sold out on Amazon in two days. There can be no escape.

For more on this earwig, check out what we’ve learned about its origins, its legal struggles, and why children can’t seem to get enough of it.

1. No one knows who wrote "Baby Shark."

The person or persons responsible for “Baby Shark” will never be brought to any kind of justice, since no one is sure who they are. The song is believed to have originated as a chant at summer camps—the kind of silly recitation that’s easy to remember and follow along with in groups. Because it didn’t need instrumental accompaniment, virtually any kid could join in.

2. "Baby Shark" is the subject of copyright controversy.

Although the lyrics to “Baby Shark” are in the public domain, the song has still produced warring factions of performers who are looking for a piece of the profits. In 2011, musician Johnny Only recorded a version of the song and uploaded it to YouTube. In 2016, South Korea-based educational content producer Pinkfong created the most well-known version to date. Only thought their rendition bore striking similarities to his, including the same key, tempo change, and rhythm. Only alleges that a political party in South Korea contacted him for permission to use the song. When he responded it was free for anyone to use, the party did, and SmartStudy—which owns Pinkfong—threatened the candidates with legal action. That motivated Only to find out if he had any claim under the idea that a freely-available song can be copyrighted if it has a unique arrangement; SmartStudy asserts that they’re the rightful owner. Only is asking a Korean court to decide who’s right.

3. Pinkfong's version of "Baby Shark" cracked the Billboard Hot 100.

According to Billboard, the song debuted on the Kid Digital Song Sales chart in July 2018 before cracking the Hot 100 the week of January 12. It debuted at No. 32 thanks to its "continued streaming growth as well as the freefall of 23 seasonal titles off the Hot 100 this week post-holidays."

4. There’s a reason "Baby Shark" is so catchy.

Like many songs targeted at children, “Baby Shark” relies on simple repetition to make sure it stays in the ears—and on the lips—of listeners. Because kids have a limited vocabulary, it’s easier for them to follow along to upbeat music with a predictable melody. They also appear to respond to the familiar domestic dynamic—there’s a baby shark, a daddy shark, a grandma shark, and so on. But there’s also a little neurological tickling at work. Valorie Salimpoor, a neuroscientific consultant, told the Daily Beast that kids bopping along to catchy music have increased activity in their dopaminergic system, eliciting feelings of pleasure. (The same goes for adults!) Essentially, your kids listening to it over and over again reinforces them to listen to it even more—like some hellish feedback loop.

5. "Baby Shark" was originally much more disturbing.

Leon Neal, Getty Images

The protagonists of “Baby Shark” are fairly reserved by shark standards. But some of the original lyrics detailed a much more violent premise, with human prey losing limbs in a blood orgy that ended in death. While that amused campers, Only realized it wouldn’t fly with toddlers. He removed the shark attack element, homogenizing the song for tiny ears.

6. "Baby Shark" was a dance hit in Germany.

Germans got a sneak preview of “Baby Shark” hysteria as far back as 2007, when the song was rendered a cappella by Alexandra Müller. “Kleiner Hai” was a little more ferocious in nature than Only’s version—the track included a screaming swimmer—and became a dance hit. EMI bought the rights and infused it with music reminiscent of the theme from 1975’s Jaws. While EMI brought it to a wider international audience, its popularity faded after a year or so.

7. There's a "Baby Shark" challenge ...

It started with people getting out of their cars and doing the "Baby Shark" dance moves (sometimes dressed as a shark) but has since expanded to people practicing CPR to the song and incorporating the moves into Zumba routines.

8. ... and a "Baby Shark" live show.

Do not be surprised if your child comes to you one day with a request to take a family vacation to South Korea. Pinkfong is promoting a Baby Shark touring live show that features the titular sea monster going missing and being tracked down by his family. It runs 65 minutes, or 63 more than the “Baby Shark” video. You've been warned.