One of the agenda items for the November 4 2014 google hangout with AJ Jacobs was about "gateway" profiles. (If you missed the hangout, full video posted here: http://www.geni.com/blog/global-family-reunion-hangout-with-aj-jaco...)
Geni kindly made a tool to find your own conection to AJ: http://www.geni.com/AJ. Chances are - the connection will be through a "gateway" ancestor.
So what is a gateway ancestor? Here's a description from genealogist Nat Taylor:
http://nltaylor.net/sketchbook/archives/11
"A gateway ancestor is an ancestor who gives descendants a treaceable path back to a new ancestral population"
In American genealogy:
"For countless Americans, whether they know it or not, and countless others of European ancestry, these gateways provide a tangible personal link to the medieval world, in the form of descents from medieval kings, queens, popes, crusaders, troubadours, heroes, villains, and saints. ..."
In other words, a gateway ancestor has these characteristics:
- pedigree is known and proven
- sufficient "notability" that you know to look for them
- they "cross borders", linking one (endogamous) population to another