[not sure if this is the best site page for this as the examples in the paper are mainly eastern USA...]
North American fluted stone projectile points occur over a relatively short time span, ca. 13,300–11,900 calBP, referred to as the Early Paleoindian period. One long-standing topic in Paleoindian archaeology is whether variation in the points is the result of drift or adaptation to regional environments.
Studies have returned apparently conflicting results, but closer inspection shows that the results are not in conflict. At one scale—the overall pattern of flake removal—there appears to have been an early continent-wide mode of point manufacture, but at another scale—projectile-point shape—there appears to have been regional adaptive differences.
In terms of learning models, the Early Paleoindian period appears to have been characterized by a mix of indirect-bias learning at the continent-wide level and guided variation at the regional level, the latter a result of continued experimentation with hafting elements and other point characters to match the changing regional environments. Close examination of character-state changes allows a glimpse into how Paleoindian knappers negotiated the design landscape in terms of character-state optimality of their stone weaponry.
https://www.academia.edu/12235135/Transmission_of_Cultural_Variants_in_the_North_American_Paleolithic
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