A 2021 study by these researchers also dated the footprints, based on tiny plant seeds embedded in the sediment alongside them, to about 21,000 to 23,000 years ago.
This paper is that corroborative exercise," added study co-lead author Kathleen Springer, also a USGS research geologist in Denver.
Scientists believe our species entered North America from Asia by trekking across a land bridge that once connected Siberia to Alaska.
The researchers also used optically stimulated luminescence dating to determine the age of quartz grains within the footprint-bearing sediments.
"And just like today, if anyone walks in a similar setting, their footprints are preserved if they are covered with another layer of sediment," Springer added.
Persons:
Jeff Pigati, Kathleen Springer, sapiens, Matthew Bennett, Bennett, Pigati, Springer, Will Dunham, Rosalba O'Brien
Organizations:
Sands, U.S . Geological Survey, Scientists, North America, Bournemouth University, Thomson
Locations:
North America, New Mexico, Illinois, Denver, Africa, Asia, Siberia, Alaska, North, England