Sherlock Holmes

Why do we take DNA tests? Reasons vary. Many people hope it will “tell me who I am.” That’s a reasonable expectation for adoptees and others with questions about their own parents and siblings. Others swab or spit because they think it will tell them where their ancestors come from. Experienced family historians turn to DNA to help resolve questions for which paper-trail research has turned up no explicit answer.

Evidence can be messy. Because it is a mental construct, it rarely gives us the clear and simple answers that we seek. Sources, by contrast, are physical; we can touch them, see them, smell them, hear them. Information is also physical, visible, audible. Evidence, however, is intangible. It’s only what we think certain information means. That’s all it can be―until we make something concrete from it by processing it and molding it into a meaningful and convincing form.

How do we do that?