Controversy about dating: corrected a typo.← Previous revisionRevision as of 14:20, 13 November 2026 Line 18: Line 18: == Controversy about dating == == Controversy about dating == In 2022, sceptics noted that age estimates relied on carbon dating ''[[Ruppia cirrhosa]]'' seeds, whose parent plants can intake older carbon from [[groundwater]], thereby potentially resulting in dates thousands of years too old.{{Cite journal |last1=Madsen |first1=David B. |last2=Davis |first2=Loren G. |last3=Rhode |first3=David |last4=Oviatt |first4=Charles G. |date=2022-10-14 |title=Comment on "Evidence of humans in North America during the Last Glacial Maximum" |url=https://www.science.org/doi/epdf/10.1126/science.abm4678 |journal=[[Science (journal)|Science]] |publisher=[[American Association for the Advancement of Science]] |volume=375 |issue=6577 |article-number=eabm4678 |doi=10.1126/science.abm4678 |pmid=35025634 |access-date=2023-08-23|url-access=subscription }} {{Cite news |last=Johnson |first=Carolyn |date=October 5, 2023 |title=Ancient footprints upend timeline of humans' arrival in North America |newspaper=[[The Washington Post]] |url=https://www.washingtonpost.com/science/2023/10/05/oldest-human-footprint-americas-white-sands/ |access-date=October 6, 2023 }} A study accounting for this effect suggested that the maximum age of the footprints is likely only 15,500–13,500 in calibrated years [[Before Present]], which is similar to the dates found for many other archaeological sites across the Americas.{{Cite journal |last1=Rachal |first1=David M. |last2=Dello-Russo |first2=Robert |last3=Cuba |first3=Matthew |date=January 2024 |title=The Pleistocene footprints are younger than we thought: correcting the radiocarbon dates of Ruppia seeds, Tularosa Basin, New Mexico |url=https://www.cambridge.org/core/product/identifier/S0033589423000741/type/journal_article |journal=Quaternary Research |language=en |volume=117 |pages=67–78 |doi=10.1017/qua.2023.74 |bibcode=2024QuRes.117...67R |s2cid=266946359 |issn=0033-5894|url-access=subscription }} In 2022, skeptics noted that age estimates relied on carbon dating ''[[Ruppia cirrhosa]]'' seeds, whose parent plants can intake older carbon from [[groundwater]], thereby potentially resulting in dates thousands of years too old.{{Cite journal |last1=Madsen |first1=David B. |last2=Davis |first2=Loren G. |last3=Rhode |first3=David |last4=Oviatt |first4=Charles G. |date=2022-10-14 |title=Comment on "Evidence of humans in North America during the Last Glacial Maximum" |url=https://www.science.org/doi/epdf/10.1126/science.abm4678 |journal=[[Science (journal)|Science]] |publisher=[[American Association for the Advancement of Science]] |volume=375 |issue=6577 |article-number=eabm4678 |doi=10.1126/science.abm4678 |pmid=35025634 |access-date=2023-08-23|url-access=subscription }} {{Cite news |last=Johnson |first=Carolyn |date=October 5, 2023 |title=Ancient footprints upend timeline of humans' arrival in North America |newspaper=[[The Washington Post]] |url=https://www.washingtonpost.com/science/2023/10/05/oldest-human-footprint-americas-white-sands/ |access-date=October 6, 2023 }} A study accounting for this effect suggested that the maximum age of the footprints is likely only 15,500–13,500 in calibrated years [[Before Present]], which is similar to the dates found for many other archaeological sites across the Americas.{{Cite journal |last1=Rachal |first1=David M. |last2=Dello-Russo |first2=Robert |last3=Cuba |first3=Matthew |date=January 2024 |title=The Pleistocene footprints are younger than we thought: correcting the radiocarbon dates of Ruppia seeds, Tularosa Basin, New Mexico |url=https://www.cambridge.org/core/product/identifier/S0033589423000741/type/journal_article |journal=Quaternary Research |language=en |volume=117 |pages=67–78 |doi=10.1017/qua.2023.74 |bibcode=2024QuRes.117...67R |s2cid=266946359 |issn=0033-5894|url-access=subscription }} A 2023 study that included radiocarbon dating of pollen and [[optically stimulated luminescence dating]] of [[quartz]] grains within the footprint layers corroborated the original dates obtained from the seeds.{{cite journal|last1=Pigati|first1=Jeffrey S.|last2=Springer|first2=Kathleen B.|last3=Honke|first3=Jeffrey S.|last4=Wahl|first4=David|last5=Champagne|first5=Marie R.|last6=Zimmerman|first6=Susan R. H.|last7=Gray|first7=Harrison J.|last8=Santucci|first8=Vincent L.|last9=Odess|first9=Daniel|last10=Bustos|first10=David|last11=Bennett|first11=Matthew R.|year=2023|title=Independent age estimates resolve the controversy of ancient human footprints at White Sands|journal=Science|volume=382|issue=6666|pages=73–75|doi=10.1126/science.adh5007 |pmid=37797035 |bibcode=2023Sci...382...73P |s2cid=263672291 |url=https://www.science.org/doi/10.1126/science.adh5007|url-access=subscription}} However, these dates have also been considered uncertain by other authors, who suggest that they represent maximum ages.{{Cite journal |last=Steffen |first=Martina L. |date=2024-02-21 |title=New age constraints for human entry into the Americas on the north Pacific coast |journal=Scientific Reports |language=en |volume=14 |issue=1 |page=4291 |doi=10.1038/s41598-024-54592-x |doi-access=free|issn=2045-2322 |pmc=10881565 |pmid=38383701}}{{Cite journal |last=Rhode |first=David |last2=Neudorf |first2=Christina M. |last3=Rachal |first3=David |last4=Davis |first4=Loren G. |last5=Madsen |first5=David B. |last6=Dello-Russo |first6=Robert |date=2024-01-02 |title=Unresolved: Persistent Problems with the White Sands Locality 2 Geochronology |url=https://www.tandfonline.com/doi/full/10.1080/20555563.2024.2345979 |journal=PaleoAmerica |language=en |volume=10 |issue=1 |pages=10–27 |doi=10.1080/20555563.2024.2345979 |issn=2055-5563|url-access=subscription }} In particular, a study published in 2024 sets forth several concerns about the methodology used to obtain the earlier dates. A 2023 study that included radiocarbon dating of pollen and [[optically stimulated luminescence dating]] of [[quartz]] grains within the footprint layers corroborated the original dates obtained from the seeds.{{cite journal|last1=Pigati|first1=Jeffrey S.|last2=Springer|first2=Kathleen B.|last3=Honke|first3=Jeffrey S.|last4=Wahl|first4=David|last5=Champagne|first5=Marie R.|last6=Zimmerman|first6=Susan R. H.|last7=Gray|first7=Harrison J.|last8=Santucci|first8=Vincent L.|last9=Odess|first9=Daniel|last10=Bustos|first10=David|last11=Bennett|first11=Matthew R.|year=2023|title=Independent age estimates resolve the controversy of ancient human footprints at White Sands|journal=Science|volume=382|issue=6666|pages=73–75|doi=10.1126/science.adh5007 |pmid=37797035 |bibcode=2023Sci...382...73P |s2cid=263672291 |url=https://www.science.org/doi/10.1126/science.adh5007|url-access=subscription}} However, these dates have also been considered uncertain by other authors, who suggest that they represent maximum ages.{{Cite journal |last=Steffen |first=Martina L. |date=2024-02-21 |title=New age constraints for human entry into the Americas on the north Pacific coast |journal=Scientific Reports |language=en |volume=14 |issue=1 |page=4291 |doi=10.1038/s41598-024-54592-x |doi-access=free|issn=2045-2322 |pmc=10881565 |pmid=38383701}}{{Cite journal |last=Rhode |first=David |last2=Neudorf |first2=Christina M. |last3=Rachal |first3=David |last4=Davis |first4=Loren G. |last5=Madsen |first5=David B. |last6=Dello-Russo |first6=Robert |date=2024-01-02 |title=Unresolved: Persistent Problems with the White Sands Locality 2 Geochronology |url=https://www.tandfonline.com/doi/full/10.1080/20555563.2024.2345979 |journal=PaleoAmerica |language=en |volume=10 |issue=1 |pages=10–27 |doi=10.1080/20555563.2024.2345979 |issn=2055-5563|url-access=subscription }} In particular, a study published in 2024 sets forth several concerns about the methodology used to obtain the earlier dates.