"Discovery of oldest footprints gives clues to Mexico's climate"
http://archaeologynewsnetwork.blogspot.com/2014/01/discovery-of-oldest-footprints-gives.html#.Usnalq-A0qQ
The oldest human footprints in North America have been dated for the first time and could help scientists to understand what Mexico's climate was like 7000 years ago.
The new climate data, published in the Journal of Archaeological Science, comes from two sets of footprints found in the Chihuahuan desert in north-eastern Mexico.
The first of these sets was discovered in 1961 after workmen stumbled across them while building a road. At the time they were removed and placed in a museum where, despite being described in detail, their provenance was lost.
'When we discovered these new prints, they were preserved in the same material as the ones in the museum. So we presumed it was a rediscovery of these lost footprints as opposed to a new discovery,' explains Dr Nick Felstead now of Durham University, lead researcher on the project.