Why are the number of generations on the map limited to 8 in the Where Am I From activity?
I can think of a few of reasons.
1) Each generation back doubles the previous generation. At some point, you are going to have so many dots the map will get too cluttered.
2) The greater the number of dots, the more processing power needed to manipulate the map. No need to bog down the entire site for what is meant to be just a fun, interesting activity.
3) Eight generations back takes you to the early to mid 1700s. At that time in history, I have heard, the vast majority of people never went more than ten miles from their birth place. So adding more people who all live in the same place, does not add any more information as to where one is from, which is the point of the activity.