SciencePleistocene/Younger Dryas (~12,900 years ago); study published 2014North Americahigh confidence

The 29-site sample examined by David Meltzer's team included Clovis sites in North America.

Notes on verification

Confirmed by the peer-reviewed PNAS paper (Meltzer, Holliday, Cannon & Miller 2014), SMU press release, ScienceDaily, and HeritageDaily coverage, all corroborating that the 29-site sample included North American Clovis sites such as Chobot, Morley, and Paw Paw Cove. [cascade flags: aggregator_dropped_primary_exists | tier=silver indep_score=0.983 clusters=3 claim_tier=notable]

Sources