On Dr. Henry Louis Gates Jr.'s Faces of America, the nutty professor revealed to his celebrity panel the interrelation between them, going back innumerable generations and using extensive DNA testing to show the stars just how close they really are.

Stephen Colbert's show persona relishes his ultra-American identity, and the real Colbert has been vocally proud of his Irish Catholic ancestry. On Faces of America, Henry Louis Gates Jr. turned Colbert's world upside-down when he revealed his hidden heritage.