[m463]

> That is the only possible explanation for how fish could have populated isolated mountain lakes

isn't that a common question?

"How do fish appear in landlocked lakes/ponds/etc"?

After digging a pond and letting it fill with rainwater/groundwater, fish appear. I don't think its because people carried them there.

(don't really know the common answer though)

[stevenwoo]

In this case they have carbon dated wooden equipment for fish farming and know due to geological factors when the lake could support fish, though of course the fish might have gotten there first somehow. I thought this was interesting because it predates agriculture in the same area.