But visible.

That is what the science achieved.

And the searching continues.

The Article’s Final Account

In a valley in the Colombian highlands, roughly six thousand years ago, people were living on a hill.

They had adapted to the altitude — the thin air, the cold nights, the particular rhythms of a life organized around highland hunting and gathering.

They knew the plateau’s resources with the intimate knowledge that generations of occupation builds.

They returned to this hill, or settled on it for extended periods, enough to build structures marked by postholes and habitation floors.