That doesn’t make them scientifically robust though. What these services are actually doing is comparing your DNA to databases of other customers—that is, other living people—and charting where on Earth they live today. The maps that you receive after a few weeks show your similarity to living populations, and from that you are to infer ancestral roots. This is not incorrect, as it reveals populations who have made a genetic contribution to your genome. It reveals a probability of a proportion of ancestry.
