Cave dig finds signs of human life over 30,000 years ago

Near the modern entrance to Chiquihuite Cave in central Mexico. Photo: Thomas L.C. Gibson.
Near the modern entrance to Chiquihuite Cave in central Mexico. Photo: Thomas L.C. Gibson.

The entrance to the Chiquihuite Cave archaeological site. Photo: Dr Ciprian Ardelean.
The entrance to the Chiquihuite Cave archaeological site. Photo: Dr Ciprian Ardelean.

The archaeological dig site at Chiquihuite Cave. Photo: Dr Ciprian Ardelean.
The archaeological dig site at Chiquihuite Cave. Photo: Dr Ciprian Ardelean.

Dr Lorena Becerra-Valdivia inside Chiquihuite Cave. Photo: Thomas L.C. Gibson.
Dr Lorena Becerra-Valdivia inside Chiquihuite Cave. Photo: Thomas L.C. Gibson.

Archaeologists collecting ancient soil DNA samples. Photo: Devin A. Gandy.
Archaeologists collecting ancient soil DNA samples. Photo: Devin A. Gandy.

Dr Ciprian Ardelean and students (from left to right: Rafael A. Martinez, Valeria M. Sánchez and Jesús De la Rosa). Photo: Dr Ciprian Ardelean.
Dr Ciprian Ardelean and students (from left to right: Rafael A. Martinez, Valeria M. Sánchez and Jesús De la Rosa). Photo: Dr Ciprian Ardelean.

A view of the valley from Chiquihuite Cave. Photo: Thomas L.C. Gibson.
A view of the valley from Chiquihuite Cave. Photo: Thomas L.C. Gibson.

Dr Lorena Becerra-Valdivia working near the entrance of Chiquihuite Cave. Photo: Thomas L.C. Gibson.
Dr Lorena Becerra-Valdivia working near the entrance of Chiquihuite Cave. Photo: Thomas L.C. Gibson.

Dr Ciprian Ardelean, who led the Chiquihuite Cave archaeological excavations. Photo: Devin A. Gandy.
Dr Ciprian Ardelean, who led the Chiquihuite Cave archaeological excavations. Photo: Devin A. Gandy.

Dr Lorena Becerra-Valdivia (centre) sampling material for radiocarbon dating alongside fellow researchers Prof. Joaquín Arroyo-Cabrales and Dr Juan I. Macías-Quintero (from left to right). Photo: Devin A. Gandy.
Dr Lorena Becerra-Valdivia (centre) sampling material for radiocarbon dating alongside fellow researchers Prof. Joaquín Arroyo-Cabrales and Dr Juan I. Macías-Quintero (from left to right). Photo: Devin A. Gandy.

A stone tool found below the Last Glacial Maximum rock layer, belonging to a material culture never seen in the Americas. Photo: Dr Ciprian Ardelean.
A stone tool found below the Last Glacial Maximum rock layer, belonging to a material culture never seen in the Americas. Photo: Dr Ciprian Ardelean.

A stone artefact found below the Last Glacial Maximum rock layer. Photo: Dr Ciprian Ardelean
A stone artefact found below the Last Glacial Maximum rock layer. Photo: Dr Ciprian Ardelean

Dr Lorena Becerra-Valdivia sampling material for radiocarbon dating. Photo: Dr Ciprian Ardelean.
Dr Lorena Becerra-Valdivia sampling material for radiocarbon dating. Photo: Dr Ciprian Ardelean.

Dr Lorena Becerra-Valdivia at the Oxford Radiocarbon Accelerator Unit (ORAU), University of Oxford. Photo: Eileen Jacob.
Dr Lorena Becerra-Valdivia at the Oxford Radiocarbon Accelerator Unit (ORAU), University of Oxford. Photo: Eileen Jacob.
Archaeological findings at the Chiquihuite Cave in Mexico suggest humans may have reached the Americas over 30,000 years ago – a period 15,000 years earlier than previously thought.
An international team of scientists – including UNSW Sydney's Dr Lorena Becerra-Valdivia (formerly of the University of Oxford) – were behind the findings.
Find out more in this Newsroom story.