RT Journal Article SR Electronic T1 Pre-Clovis occupation 14,550 years ago at the Page-Ladson site, Florida, and the peopling of the Americas JF Science Advances JO Sci Adv FD American Association for the Advancement of Science SP e1600375 DO 10.1126/sciadv.1600375 VO 2 IS 5 A1 Halligan, Jessi J. A1 Waters, Michael R. A1 Perrotti, Angelina A1 Owens, Ivy J. A1 Feinberg, Joshua M. A1 Bourne, Mark D. A1 Fenerty, Brendan A1 Winsborough, Barbara A1 Carlson, David A1 Fisher, Daniel C. A1 Stafford, Thomas W. A1 Dunbar, James S. YR 2016 UL http://advances.sciencemag.org/content/2/5/e1600375.abstract AB Stone tools and mastodon bones occur in an undisturbed geological context at the Page-Ladson site, Florida. Seventy-one radiocarbon ages show that ~14,550 calendar years ago (cal yr B.P.), people butchered or scavenged a mastodon next to a pond in a bedrock sinkhole within the Aucilla River. This occupation surface was buried by ~4 m of sediment during the late Pleistocene marine transgression, which also left the site submerged. Sporormiella and other proxy evidence from the sediments indicate that hunter-gatherers along the Gulf Coastal Plain coexisted with and utilized megafauna for ~2000 years before these animals became extinct at ~12,600 cal yr B.P. Page-Ladson expands our understanding of the earliest colonizers of the Americas and human-megafauna interaction before extinction.