It started with an email. Three years ago, author A.J. Jacobs opened his inbox and found a message from a man claiming to be his eighth cousin. While he initially suspected he was the target of a cheap scheme — "I thought he was going to ask me to wire him $10,000 to a Nigerian bank," Jacobs said — he soon realized the guy was legit and was actually part of a project that would change Jacobs's life. The cousin, and soon Jacobs himself, became involved in the World Family Tree, a massive online project through which millions of people are exploring their backgrounds. The project allows these people to explore how their paths diverged from the two people from whom everybody on earth is descended — "Y-Chromosomal Adam" and "Mitochondrial Eve" — and allows them to make current connections to others.

Jacobs, known for things like his impressive commitment to living exactly as people did in Biblical times, decided to take on the World Family Tree with gusto, exploring everything from the great cultural divides of our time to whether or not the Beyhive are technically Beyonce's long lost cousins. Jacobs told MTV News about this experience and his book that chronicles it: It's All Relative: Adventures Up and Down the World's Family Tree. 

MTV News: Can you tell us about why you loved the idea of the World Family Tree so much as to pursue your own genealogical project?

A.J. Jacobs: The World Family Tree is one of the biggest family trees in history. It is mind-bogglingly huge: Millions of people [are] all on the same family tree [from] dozens of countries, hundreds of ethnicities — and we’re all related.

I just loved this idea that humanity is one big family. We’ve heard it since we were kids, but now scientifically we can see how exactly this happens. We can see the links concretely. I thought this affects everything: our identities, race relations, politics. I thought this should be the topic of my next book.

MTV News: You argue that a greater understanding of genealogy could potentially help us address the cultural divisiveness in our country — like the resurgence of white supremacy, for example. How do you think it can do this?

Jacobs: We are in this moment of divisiveness and separation like I’ve never seen. Tribalism everywhere — Democrats vs. Republicans, city vs. country. It’s very disturbing. My great hope with this [project] is that it will have a huge positive impact on the way we see ourselves.

A big theme of the book [is that] we are all much more of a mix DNA-wise and ethnicity-wise than we suppose. Henry Louis Gates, a Harvard professor, is an advisor on the book and [he explains] that there’s no such thing as racial purity. [For example,] the average African American has about 24 percent European DNA and caucasians are a mix as well. It’s fascinating to see how some white supremacists react when they find out they’re African American or have Jewish DNA. Sometimes they’re in denial: They say ‘that’s just a multicultural conspiracy.’ Others are more open to it and even have a Hollywood-like revelation, a change of heart, and realize hating another so-called tribe is not the way to go through life.

The hope is also that the more you stress that we share 99.9 percent of our DNA, the more people will start to see commonalities and not be obsessed with our differences. There was a study done by Harvard last year where they took two groups of Palestinians and Israelis and showed one how they were related [to each other] and didn't show [that relation to] the other. The group that knew how closely they were related was kinder to each other and more open to negotiations. It’s this idea that maybe we will treat each other with just a little more kindness, or a little less horribleness, when we realize how close we are.

MTV News: Similarly, do you think this same idea could help us understand and even heal the political divide that currently exists in our country?

Jacobs: It would be nice if someone could explain to the two [political] parties how closely they’re related. Who knows if it would make a difference but it certainly can’t hurt. We can’t get worse than we are now with the tribalism in the Congress.

In the book, I tell the story of a meteorologist who lives in Texas. He did a DNA test and found out he was adopted. He found his biological mom and it turned out she was a very conservative, Evangelical Christian who did not approve of homosexuality. He’s gay and through meeting her and talking to her, he was able to open her mind. She became accepting of him and his husband. So that’s sort of the great hope — that by meeting other people they will become more tolerant.

MTV News: On a lighter note, you also connected with a number of celebrities to whom you’re distantly related. Can you tell us about those experiences?

Jacobs: I loved hearing the family stories of these people. Daniel Radcliffe, for instance, talked about how his grandmother married a man from South Africa. When she moved there, he turned out to be a horrible person — a racist who tried to have her committed to an insane asylum. Daniel’s great grandma had to fly to South Africa to rescue her. It was a thriller — it sounds like someone should option Daniel Radcliffe’s family story.

I interviewed Ludacris and was in the weird position of telling him about his own family, including that one of his great, great grandfathers was probably Jewish, which he didn’t know. He was a little taken aback at the start of the phone call but by the end I think he enjoyed it. I told him since I’m Jewish we’re ‘mishpacha’ which means ‘family.’

MTV News: Did realizing these connections to celebrities teach you anything more broadly about fame itself?

AJ Jacobs: It makes celebrities a little less distant, a little less intimidating when you realize we’re all related. The farthest cousin you have on Earth, according to some scientists, is about a 70th cousin, which is not all that far. I feel the same way about royalty. If you look at the map, at the statistics, everyone on Earth is descended from royalty — it’s just about whether or not you know it because you have so many hundreds of thousands of ancestors. So don’t be intimidated by someone with a fancy background. We all have great people in our background and we all have tons of thieves and embezzlers. We’re all a mix of the high and low.

MTV News: What do you think are your biggest takeaways from this project — both personally and in terms of your worldview?

Jacobs: We should broaden the idea of family. Like my eighth cousin three times removed, Hillary Clinton, says, ‘it takes a village.’ I like the idea that family doesn’t have to be just your parents or grandparents — it doesn’t have to be people who share your DNA. There’s the biological family, but there’s also the logical family. That can be friends from school or people you work with, people who share a passion. The idea that we can have lots of different people we call family is a really nice message. The Juggalos consider themselves a family. So do people in the Beyhive. The idea that we can have lots of different people we call family is a really nice message.

MTV News: Can you elaborate on that idea of fandom as family? And what are the chances that members of the Beyhive, for example, are actually related themselves to Beyonce?

Being in the Beyhive — that's sort of a modern version of a big, extended family. They Feel a kinship, they support each other and their matriarch, Beyoncé. And now, with these massive family trees, they can even see how they are cousins with Beyoncé.