[sandworm101]

>> mostly in a small town in Australia for centuries after her ancestor was taken there during British colonization.

Not that many centuries. Australia was colonized very recently. Go to placed like the middle east or china and families may have been in the same area for thousands of years.

[asveikau]

I think you probably find some degree of that in Europe too until quite recently, notwithstanding some famous major wars and territorial shifts...

It's an anecdote, but I was pretty impressed when my uncle recently signed up for one of those ancestry tests, and it correctly pinpointed exactly the region that his grandfather (my great-grandfather) had come from in the late 19th century. I'm certainly no expert in the genetics but it boggles my mind a bit that it's detectable that his recent lineage didn't stray much from that small area of Europe until it went to the States. I share 50% of my ancestry with him, the other 50% is from other parts of Europe, my wife is from another part with its complicated story, and we have kids... After 3 generations I don't think any one particular country should be particularly recognizable (though I'll admit, I may be over-simplifying or misunderstanding how it works). Yet my uncle's DNA test pinpointed a small place in Europe with only a few hundred thousand people, and did so correctly.

[sandworm101]

Be very careful of those tests. Look at who is running them, often a particular church. Many have questioned their methodology. Not of the testing per se, but in how they selected their sample "representative" populations. They didn't do the science to determine whether a sample person was really representative, beyond some questionnaires. And their sampling was based on a particular world view, one that locked populations down circa 150 years ago into modern national boundaries and ignoring previous migrations.