As far as I can tell, the Twitter hashtag #wordsthatleadtotrouble got started at about 11 a.m. Pacific Time on Sunday morning, when a user named Kookeyy posted this short message: “#wordsthatleadtotrouble ‘Don’t Worry I gotchu.” A couple minutes later, Kookeyy posted another take on the same theme: “#wordsthatleadtotrouble - I Love Yuh *kiss teeth*.” On Twitter, people append hashtags to categorize their messages—the tags make it easier to search for posts on a certain topic, and they can sometimes lead to worldwide call-and-response conversations in which people compete to outdo one another with ever more hilarious, bizarre, or profane posts. A woman in South Africa named Tigress_Lee moved the chatter in that direction: “#wordsthatleadtotrouble ‘the condom broke’!”she wrote. From there, the meme took off. “We need to talk #wordsthatleadtotrouble,” declared BigJamaal (11,920 followers), and then he proceeded to post a blizzard of suggestions, including “#wordsthatleadtotrouble I dont know why you got that Magnum in your wallet you clearly live a Durex lifestyle.”

Over the next few hours, thousands of people added to the meme. According to Trendtistic, a site that monitors and archives hot Twitter topics, #wordsthatleadtotrouble was one of Twitter’s top 20 hashtags on Sunday, and it was the top tag that was not based on some real-life event (like the Teen Choice Awards or football). By Monday morning, Twitter was displaying #wordsthatleadtotrouble on its list of “trending topics.” If you’d clicked on the tag, you would have noticed that contributions to the meme ranged from the completely banal (“#wordsthatleadtotrouble we just going out with friends!”) to the slightly less so (“#wordsthatleadtotrouble I didn’t know she was your sister”). If you clicked when the meme was at its peak—that is, before it spread widely beyond the cluster of people who started it—you would have also noticed something else: To judge from their Twitter avatars, nearly everyone participating in #wordsthatleadtotrouble was black.

Call #wordsthatleadtotrouble a “blacktag”—a trending topic initiated by a young African-American woman in Hollywood, pushed to a wider audience by a black woman in South Africa, and then pushed over the top by thousands of contributions from users who appear to be black teenagers all over the United States. This story is not at all out of the ordinary on Twitter. #wordsthatleadtotrouble was one of a few such tags that hit the trending topics list on Monday—others included #ilaugheverytime and #annoyingquestion—and it’s typical of the sort of tag that pops up almost daily. (A new one, #wheniwaslittle, hit Tuesday morning.)

The prevalence of these tags has long puzzled nonblack observers and sparked lots of sometimes uncomfortable questions about “how black people use Twitter.” As the Awl’s Choire Sicha wrote last fall, “At the risk of getting randomly harshed on by the Internet, I cannot keep quiet about my obsession with Late Night Black People Twitter, an obsession I know some of you other white people share, because it is awesome.”

As a nonwhite person, I must concur: It is awesome—although I’m less interested in the content of these tags than in the fact that they keep getting so popular. What explains the rise of tags like #wordsthatleadtotrouble? Are black people participating in these types of conversations more often than nonblacks? Are other identifiable groups starting similar kinds of hashtags, but it’s only those initiated by African-Americans that are hitting the trending topics list? If that’s true, what is it about the way black people use Twitter that makes their conversations so popular? Then there’s the apparent segregation in these tags. While you begin to see some nonblack faces after a trending topic hits Twitter’s home page, the early participants in these tags are almost all black. Does this suggest a break between blacks and nonblacks on Twitter—that real-life segregation is being mirrored online?

After watching several of these hashtags from start to finish and talking to a few researchers who’ve studied trends on Twitter, I’ve got some potential answers to these questions. Black people—specifically, young black people—do seem to use Twitter differently from everyone else on the service. They form tighter clusters on the network—they follow one another more readily, they retweet each other more often, and more of their posts are @-replies—posts directed at other users. It’s this behavior, intentional or not, that gives black people—and in particular, black teenagers—the means to dominate the conversation on Twitter.

There are loads of caveats to this analysis, which I’ll get to in a moment. But first, a digression into one of the leading explanations for these memes—the theory that the hashtags are sparked by something particular to black culture. “There’s a long oral dissing tradition in black communities,” says Baratunde Thurston, the Web editor of the Onion, whose funny presentation at this year’s South by Southwest conference, “How To Be Black Online,” argued that blacktags were a new take on the Dozens. “Twitter works very naturally with that call-and-response tradition—it’s so short, so economical, and you get an instant signal validating the quality of your contribution.” (If people like what you say, they retweet it.)

To me, the Dozens theory is compelling but not airtight. For one thing, a lot of these tags don’t really fit the format of the Dozens—they don’t feature people one-upping one another with witty insults. Instead, the ones that seem to hit big are those that comment on race, love, sex, and stereotypes about black culture. Many read like Jeff Foxworthy’s “You might be a redneck …” routine applied to black people—for instance, last December’s #ifsantawasblack (among the tamer contributions: “#ifsantawasblack he wouldnt say ho ho ho, he would say yo yo yo”) or July’s #ghettobabynames (e.g., “#ghettobabynames Weavequisha.”) The bigger reason why the Dozens theory isn’t a silver bullet is that a lot of people of all races insult one another online generally, and on Twitter specifically. We don’t usually see those trends hit the top spot. Why do only black people’s tweets get popular?

In April, Edison Media Research released a survey which found that nearly one-quarter of people on Twitter are African-American; the firm noted this was “approximately double the percentage of African-Americans in the current U.S. population.” That survey has been widely cited as an explanation for the popularity of blacktags, but as Fred Stutzman later pointed out, Edison’s survey had a high margin of error, and thus didn’t really tell us much about how many black people use Twitter. In general, it’s difficult to get demographic information about Twitter users—you don’t have to tell the service your age, race, ethnicity, or geographic location when you join. As such, when we talk about black Twitter users, we’re usually talking about people who’ve chosen photos of black people as their avatars. This lack of reliable demographic information has hampered many efforts to get to the bottom of this phenomenon.

Nevertheless, Brendan Meeder thinks he’s got a good hypothesis about what’s going on. Meeder, a Ph.D. student at Carnegie Mellon University, has downloaded the tweets of more than 100 million users. (Twitter gave him special permission to do so for research purposes.) He’s been probing this collection to see how Twitter users interact with one another; he’s particularly interested in how trends begin and spread through a social network. While analyzing his database a few months ago, Meeder noticed something strange—he found a cluster of hundreds of users whose profiles were connected to one another. When he looked up the users, he noticed that a lot of them were black. It’s in exactly these kinds of tight-knit groups that Twitter memes flourish, Meeder says. “It’s my impression that these hashtags start in dense communities—people who are highly connected to each other,” Meeder says. “If you have 50 of these people talking about it, think about the number of outsiders who follow at least one of those 50—it’s pretty high at that point. So you can actually get a pretty big network effect by having high density.”

Not only are the people who start these trends more tightly clustered on the network, they’re also using the network differently. Most people on Twitter have fewer followers than the number of people they’re following—that is, they’re following celebrities, journalists, news organizations, and other big institutions that aren’t following them back. But according to Meeder, the users who initiate blacktags seem to have more reciprocal relationships—they’re following everyone who follows them. Tigress_Lee, the user who helped spark #wordsthatleadtotrouble, has 1,825 followers, and she’s following 1,873. BigJamaal has 11,962 followers, and he’s following 11,203. These patterns suggest that the black people who start these tags “are using Twitter as a social tool,” Meeder says. “They’re using Twitter like a public instant messenger”—using the service to talk to one another rather than broadcast a message to the world.

Now for the caveats. There is an obvious problem with talking about how black people use Twitter, as many of the black Twitter users I spoke to took pains to point out: Not all black people on the service are participating in these hashtags, and there are probably a great many who are indifferent to or actively dislike the tags. “It’s the same issue I have with certain black comedy shows,” says Elon James White, a comedian who runs the site This Week in Blackness. “They put out these ideas of blackness that—if it were someone of another race saying them—you’d go, ‘Whoa, that’s racist!’ I remember when #ifsantawasblack hit, I lost my shit. I was freaking out. It was literally a game of, What’s the most racist thing we can say? And it was black people saying it!”

Omar Wasow, a co-founder of BlackPlanet.com and a contributor to Slate’s sister publication The Root, was one of several black people who told me that he rarely sees the people in his timeline joining these hashtags. “If you’re not a teen or twentysomething and probably working class, you’re likely not following these people, and you’re out of the loop,” he says. Like me, Wasow says he only notices these conversations when they hit Twitter’s trending lists.

Given that these hashtags are occurring in a subgroup of black people online, it is probably a mistake to take them as representative of anything larger about black culture. “For people who aren’t on the inside, it’s sort of an inside look at a slice of the black American modes of thought,” says Jonathan Pitts-Wiley, also a former writer at The Root. “I want to be particular about that—it’s just a slice of it. Unfortunately, it may be a slice that confirms what many people already think they know about black culture.”

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