Early Footprints Kick Up a Storm
Human occupation of the Americas is not supposed to be much older than 12,000 years. A spear point found in mammoth remains in 1932 has long been the earliest solid evidence of humans living in the New World. The find was rigorously dated to about 11,200 years ago and came from a culture called the Clovis. In 1977 anthropologist Tom Dillehay of Vanderbilt University in Tennessee found the remains of a human settlement at Monte Verde, Chile, that was at least 1,000 years older.
Since then, mounds of disputed evidence have been unearthed, from Pennsylvania to the Amazon, in the search for signs that someone got here even earlier. The latest and most controversial candidate surfaced when a team of investigators led by Sylvia Gonzalez of Liverpool John Moores University in England announced in August the discovery in central Mexico of human footprints that they claim are at least 40,000 years old.
The evidence came to light in 2003 when Gonzalez, along with David Huddart of LJMU and Matthew Bennett of Bournemouth University in England, were studying a formation of volcanic ash in the Valsequillo Basin, south of Puebla. There they spotted lines of small depressions in an area of hardened ash that had long been quarried by locals. Gonzalez spent the next two years studying the depressions. She and her team dated the site by several methods with several dating laboratories and announced that some of the marks were footprints made by ancient humans. The study has been accepted for publication in Quaternary Science Reviews.
