It is evidence that the record, if it exists, is inaccessible to current methods.

The people who crossed from Asia to North America — the people who made the crossing that put the Bluefish Caves butchers’ ancestors in eastern Beringia — left their traces in a landscape that is now beneath the sea.

Bluefish Caves, because it is in eastern Beringia rather than on the central land bridge, happened to be above the sea level of the Last Glacial Maximum and remains above present sea level.

This geographic accident — the specific location of the caves on a limestone ridge in the northern Yukon — is what preserved the evidence.