The aftershocks of Tuesday’s stunning announcement that Brad Pitt and Angelina Jolie are divorcing continue to reverberate around the world. Endless articles, gossip columns, newspaper front pages and social media posts devoted to the famous celebrity couple relentlessly try to feed the public’s appetite for juicy details surrounding the breakup. Two days after TMZ first broke the news, the Pitt-Jolie drama is still dominating the internet.

So why do we care about a couple who we’re likely never going to meet and who don’t even know we exist?

Frank McAndrew, a psychologist at Knox College in Galesburg, Ill., has one theory which stems back tens of thousands of years. McAndrew told CTVNews.ca on Thursday that our obsession with celebrities is a product of our primal need to keep track of our peers to compete. He said that our cavemen ancestors lived in little groups and created social structures based on knowledge of individuals’ dominance, romances, rivalries, friendships and resources. The more information someone had about their group members, the more power they had to get ahead.

“People who were driven to be busybodies did better than people who just didn’t care because they were more successful at navigating the social world,” McAndrew said.

McAndrew believes that we are programmed to care about others who are socially important to us. He said this primal instinct to gather material on our neighbours has evolved from the cavemen period. Even though celebrities, such as Pitt and Jolie, aren’t in our primary social circle, we still register them as socially important because we feel like we know them, according to McAndrew.

“I think our caveman brains get tricked by 21st century technology,” he said. “Let’s face it, you know more about Brad and Angelina than your next-door neighbour probably.”

McAndrew said that this social programming isn’t just limited to entertainment culture. He said that even if you’re not very concerned about Jolie and Pitt, there is probably someone else, such as an athlete or politician, who you’re interested in knowing about.

“We’re all walking around interested in certain strangers, but we’re interested in different strangers,” he said.

After news of the divorce broke, the internet exploded with a deluge of comments, posts, photos and memes about the celebrity couple. McAndrew argues that our impulse to share the juicy gossip with each other relates to how we create bonds. In a workplace environment, coworkers tell secrets about others to the colleagues they trust.

“If you don’t participate in the gossip network at work, you’re saying you don’t trust them and that you don’t want to be a part of their group,” McAndrew said.

In the case of Brangelina, that same impulse to share the news with our friends, family and coworkers applies. McAndrew said that it’s the same on social media; the only difference is that we now have a bigger megaphone to share the information.

“Our interest in other people and our irresistible urge to talk about them, all come from the same evolutionary need to keep up with others and monitor their reputations,” he said.

As soon as Jolie filed for divorce, everyone immediately leapt to different conclusions about who was to blame for the split. McAndrew said that our obsession with identifying who the guilty party is relates to our overall need to know as much as we can about the socially important people in our lives.

“We’re obsessed with other people’s reputations as well as our own,” he said.

McAndrew believes that we all take sides with different celebrities during a conflict because we feel like we know some of them better than others.

“They’re just like other people in our social world. You like some of them more than others,” he said. “You have more of a history with some of them than others.”