Also surnames like d'Urberville? (Alec d'Urberville in "Tess of the d'Urbervilles" is a nouveau riche person who adopted the name rather than a descendent of t

Also surnames like d'Urberville? (Alec d'Urberville in "Tess of the d'Urbervilles" is a nouveau riche person who adopted the name rather than a descendent of the original d'Urbervilles. Probably that happens in real life, too, though I expect the people who did the study have taken that into account and have done the best they can in the absence of reliable public ancestry data.)