More signs emerge of New World settlers before 20,000 years ago

New finds support the controversial idea that people inhabited South America before Clovis hunters reached North America around 14,000 years ago. Two sets of simple stone tools excavated at the base of a rocky slope in northeastern Brazil were made by small groups of settlers, one that lived about 24,000 years ago and another from around 15,000 years ago, researchers say.

The ancient site, Vale da Pedra Furada, lies near other proposed pre-Clovis camps (SN: 4/20/13, p. 9), a team led by archaeologist Eric Boëda of Université Paris Ouest Nanterre La Défense reports in the September Antiquity. Microscopic marks on 294 unearthed stones indicate that humans had sharpened the rocks. Radiocarbon dating of burned wood and soil analyses yielded ages for those stones. The new findings challenge a long-standing view among archaeologists that Clovis people first settled the Americas.

If the new dates hold, makers of un-Clovis-like tools trickled into South America before 20,000 years ago, writes archaeologist Kjel Knutsson of Sweden’s Uppsala University in a comment published in the same Antiquity. But the sharp stones may have been created by natural events, such as rock slides, or shifted into 24,000-year-old soil from younger sediment layers, write Brazilian archaeologists Adriana Schmidt Dias of the Federal University of Rio Grande do Sul in Porto Alegre and Lucas Bueno of the Federal University of Santa Catarina in Florianόpolis in another comment.