Paleo-era tools from California's Channel Islands

A report in Science this month provides details about lithics recovered from the Channel Islands:

The Paleocoastal sites, dated between ~12,200 and 11,200 years ago, contain numerous stemmed projectile points and crescents associated with a variety of marine and aquatic faunal remains... provide evidence for seafaring and island colonization by Paleoindians with a diversified maritime economy.

As explained at the BBC, these finds support the idea that the original visitors to the Americas were

seafarers, rather than arriving via an "ice-free corridor" between Canadian glaciers.

"The tools that the team found hold the greatest surprise, however, in that they differ significantly from those of mainland cultures like the Clovis and Folsom. Points found on the islands - which could even be arrow-heads - are thin, serrated, and have barbed points that show striking workmanship for the period..."

"What they tell us is that there was widespread cultural diversity at the outset of human entry and dispersion throughout the Americas, and that the old, now-dead Clovis first model often misleads us to believe that there was only one major way of first human expansion throughout the Western Hemisphere."