CROPfm Forum

Footprints left in volcanic ash that fell in central Mexico’s Valsequillo Basin about 40,000 years could be evidence that humans have inhabited the Americas far longer than previously confirmed. Laser scans of the prints (right) confirm their human origins, the researchers report today at the American Geophysical Union meeting.

The first Americans may have arrived at least 25,000 years earlier than thought, new methods of dating ancient footprints show.

The analysis centered on 325 indentations found in a quarry in present-day Mexico's Valsequillo Basin.