Check out this post to see an illustration of the three degrees of separation between guests on Finding Your Roots.When we learn about our ancestors, who they were and where they came from, the discoveries become part of how we define ourselves and how we understand ourselves to be unique. The PBS series Finding Your Roots has taken this a step further, showing us how much we share with others and how interconnected our stories are.Stanley Milgram from experiments he did in the late 1960s. It’s a little more complicated than what Milgram theorized but he got the gist right.“Six Degrees of Kevin Bacon.” The game links any actor to Kevin Bacon by five other performers. Bacon – whose wife Kyra Sedgewick was also on the show – said for a long time he hated that his name was the punchline for a joke. But he has since embraced it and is using the idea of social connections to link people to worthy causes.More recently Facebook and LinkedIn have shown that just four “connections” could link any two people together.Macpherson connected the Finding Your Roots guests via a much shorter genetic chain. Any two people are connected through just one or two other individuals.Why is this a revelation?It’s new because this isn’t the notion that you are connected to someone else because of who you know. It’s the notion that you are connected to someone because of who you are related to.This is a manifestation of human history and human migration over the last 500 years. People are no longer isolated by geography and so the differences between people are smaller than in the past .Perhaps in no other place has the convergence of people of different cultures and histories been as dramatic as the Americas. And while the clash of cultures and histories has been both painful and brutal at times, it is what forged our history more than anything else, Gates argues.“I’ve always thought that it was that story of America,” said political commentator Linda Chavez in the last episode in the series.People came here from all over the world, some voluntary and some involuntary, and mixed, she said, “and that’s made us stronger.”This post by 23andMe Content Editor Scott Hadly and 23andMe Senior Director of Research Joanna Mountain first appeared last week on PBS’s Finding Your Roots website. It was one of a series of posts by 23andMe. Dr. Mountain was a consultant for the the 10-part series.