Clovis sites are found across a wide geographic area, from the American Southwest to the Atlantic coast, and the consistency of the technology across this broad area suggests a rapid demographic expansion.

For decades, Clovis was treated as the archaeological signature of the first Americans — the evidence of a population that entered the Americas and spread rapidly across the continent.

The “Clovis first” model was the dominant paradigm for American prehistory through much of the twentieth century, supported by a body of well-dated archaeological evidence and defended vigorously by many researchers.

Under this model, any claim for human presence in the Americas before the Clovis horizon — any “pre-Clovis” claim — was treated with extreme skepticism, and the many sites that claimed to document earlier human presence were often dismissed on methodological grounds.

The methodological skepticism was not entirely wrong.