NaturePrehistoricAmericashigh confidence

Within 1,000 years of humans migrating into the Americas, more than 114 species of large plant-eaters, including woolly mammoths, giant camels, and ground sloths, went extinct.

Notes on verification

Matches peer-reviewed Nature Geoscience study (Smith et al. 2010) and is corroborated by multiple independent secondary sources (phys.org, Smithsonian, science blog) reporting the same 114-species figure and 1,000-year timeframe. [cascade flags: aggregator_dropped_primary_exists | tier=silver indep_score=0.95 clusters=3 claim_tier=notable]

Sources