It’s part of human nature: we look at ourselves in the mirror and see links to the past. “Those bright green eyes?” we think. “Those came from grandma.” “The cleft chin? That’s from dad’s side.” Our instinct, of course, is to attribute notable traits to close relatives – those that we know personally or through family history. The reality, however, is that the genetics that influence our traits – or “phenotypes” – could date back generations.