Hueyatlaco

After excavations in the 1960s, the site became notorious due to geochronologists' analyses, which have found wildly contradictory estimates for human habitation at Hueyatlaco dating from ca.

[1][2] If correct, these controversial findings would substantially exceed the previous oldest-known evidence for habitation of the New World (the White sands footprints dating roughly 22,000 ybp).

At the high end, they would imply that archaic humans settled the Americas prior to Homo sapiens, although such estimates are considered wildly implausible by archaeologists.

Furthermore, in 1969 Irwin-Williams[1] cited statements of support from three prominent archeologists and anthropologists (Richard MacNeish, Hannah Marie Wormington and Frederick A. Peterson) who had each visited the site independently and attested to the integrity of the excavations and the professionalism of the group's methodology.

[5] Moreover, the team undertook an exhaustive analysis of volcanic ash and pumice from the original excavation site and the surrounding region.

[5] The confirmation of an anomalously distant age for human habitation at the Hueyatlaco site led to tension between Irwin-Williams and the other team members.

The delays forced Steen-McIntyre to write her doctoral dissertation not on Hueyatlaco as planned, but rather on the dating of volcanic ash in geographic strata.

In 1981, the journal Quaternary Research published a paper by Steen-McIntyre, Fryxell and Malde that defended an anomalously distant age of human habitation at Hueyatlaco.

Steen-McIntyre claims that some of the original research team were harassed, viewed as incompetent, or saw their careers hampered due to their involvement in such a controversial and anomalous investigation.

[5] In 1990, Frison and Walker discuss possible pre-clovis sites dating to perhaps 20,000 ybp but argued against human habitation of Hueyatlaco ca.

In 2008 during a Geological Society of America conference, Joseph Liddicoat presented paleomagnetic research into the volcanic ash at Hueyatlaco.