Did he? People change ethnicity over time so the ethnicity of your ancestors isn't necessarily the same as yours. I am always curious as to what people being by ethnicity. Maybe ethnic ancestry would be a better way of putting it as that's what those tests would get you a glimpse of

Actually I wasn't thinking much about the distinction. People seem to want some kind of assurance about their identity. Also why they take personality tests.

People get DNA tests for their dogs.