Every sourdough baker recalls who gave them their starter, or how they made their own. I have made it a practice to share My Three Starters (for those of you of a certain age, I apologize for putting the insipid jingle for My Three Sons in your head), though I sell them now, mostly so I am not inundated by too many requests.
Now that one of my longest-running sourdough friends moved with her Cripple Creek starter from Germany to Australia, I can now say that sourdough starters I bake with are alive and leavening loafs on every continent except Antarctica.
You’ll have to read Sourdough Culture: The History of Breadmaking from Ancient to Modern Bakers to learn whether sourdough cultures morph when they move to a new home. While you are reading, you will learn whether old sourdough cultures, like wines, improve with age.
The sourdough map is constantly being updated and you can see who is baking with which starter on the live view of the sourdough map.