In New Mexico’s White Sands National Park, a remarkable discovery of fossilized human footprints is challenging long-held beliefs about when humans first arrived in the Americas. These ancient tracks, found alongside a dried-up ice age lake bed, have been dated to between 21,000 and 23,000 years ago, potentially pushing back the timeline of human presence in the region by several thousand years.
The footprints were first discovered in 2009, with their age initially determined through radiocarbon dating of aquatic plant seeds found in the sediment layers. This dating method sparked controversy, as some scientists questioned whether the plants might have absorbed ancient carbon from groundwater, potentially skewing the results.
To address these concerns, researchers employed additional dating techniques. They radiocarbon dated pollen from land plants found in the same layers as the footprints and used optically stimulated luminescence to date quartz grains above the lowest footprints. Both methods corroborated the original age estimate, strengthening the case for human presence in the Americas much earlier than previously thought.
The White Sands site contains an extensive collection of fossilized tracks, with estimates suggesting hundreds of thousands of prints from both humans and extinct ice age animals. These prints offer invaluable insights into the interactions between early humans and megafauna such as Columbian mammoths, ground sloths, and dire wolves.
Interestingly, most of the human footprints appear to belong to teenagers and children, with fewer adult prints present. This pattern has led researchers to hypothesize about possible divisions of labor in these ancient communities.
