23,000-Year-Old Footprints Push Back Human Presence in North America
2025-06-20
Ancient human footprints discovered at White Sands National Park in New Mexico have had their age reaffirmed. Initial radiocarbon dating placed them between 23,000 and 21,000 years ago, but this was challenged due to concerns about groundwater contamination of aquatic plant samples. The team retested using radiocarbon dating on pollen from the same layers (pine, spruce, and fir), and optically stimulated luminescence dating on quartz grains above the lowest footprint layer. The new results corroborate the original age estimate, confirming the footprints' antiquity and suggesting human presence in the region before ice sheets isolated southern North America.