Dating Something Older Than The Accepted Story

The original radiocarbon dates from the Manis site had produced ages in the range that placed the site at or just before the Clovis horizon.

But those dates came from methods and materials that were not optimal for establishing the precise age of remains this old and this potentially important.

By the late 1990s and early 2000s, accelerator mass spectrometry — AMS radiocarbon dating — had become the standard method for dating small or precious organic samples.

Conventional radiocarbon dating required relatively large samples and measured the radioactive decay of carbon-14 in those samples over time.