My original interest in this idea was the Social Anthropological assertion that during most of human history, people have lived in small, isolated communities of between three and five hundred people. In nineteenth century rural England the radius of the pool of potential spouses was about five miles which was the distance a man could comfortably walk twice on his day off when he went courting. This meant that after six generations or so there are only third cousins or closer to marry and have in fact probably been closer to the genetic equivalent of first cousins. I'm not sure how much this is considered in "normal" family history charting but this project does seem to confirm it in microcosm.
Alan
Having been brought up in a small village I have always had a problem with the distances expressed in such studies.
The reason being some my school friends from outlying farms would walk at least three miles before getting to the road where the school bus would take them to school and would be faced with a similar walk after being dropped off by the bus after school 5 days a week including winter. In addition miners often had long walks to the coal face from the bottom of the shaft.
Five miles may seem a long walk to modern eyes but to our ancestors five miles was commonplace and I would suggest ten would be a more realistic “distance a man could comfortably walk twice on his day off when he went courting”.
Think of it this way if your ancestor lived five miles from the market (a commonly claimed travel distance for a trader to travel to market) and met someone he/she was attracted to at the market it would be quite likely that they had come from a different direction to the market than he/she.
The distance they lived from each other could therefore easily be up to ten or twelve miles.
Think also if they could travel five miles back from market carrying purchases, they could surely travel twice that distance to visit the girl they were attracted to.
Cheers
Guy