The difference is significant: roughly 2,000 calendar years separate the raw radiocarbon date from the calibrated calendar date.

Thirteen thousand years ago, not eleven thousand.

The terminal Pleistocene, not the early Holocene.

The last Ice Age, not its aftermath.

In the context of North American prehistory, those 2,000 years matter enormously.

They push the Arlington Springs individual back before the traditional Clovis chronological horizon — the period to which the most dramatic early-American debate had been attached — and into a period when, under the old Clovis-first model, there should not have been anyone anywhere near the California coast.

What Later Geology Confirmed