Fossilised footprints found in New Mexico point out that early people had been strolling throughout North America round 23,000 years in the past, researchers stated.
he first footprints had been present in a dry lake mattress in White Sands Nationwide Park in 2009.
Scientists on the US Geological Survey just lately analysed seeds caught within the footprints to find out their approximate age, starting from round 22,800 and 21,130 years in the past.
The findings might make clear a thriller that has lengthy intrigued scientists on when folks first arrived within the Americas after spreading out from Africa and Asia.
Most scientists consider historic migration got here by the use of a now-submerged land bridge that related Asia to Alaska.
Based mostly on varied proof – together with stone instruments, fossil bones and genetic evaluation – different researchers have supplied a spread of potential dates for human arrival within the Americas, from 13,000 to 26,000 years in the past or extra.
The present examine supplies a extra stable baseline for when people positively had been in North America, though they might have arrived even earlier, the authors say.
Fossil footprints are extra indeniable and direct proof than “cultural artefacts, modified bones, or different extra typical fossils,” they wrote within the journal Science, which revealed the examine on Thursday.
“What we current right here is proof of a agency time and placement,” they stated.
Based mostly on the dimensions of the footprints, researchers consider that at the least some had been made by youngsters and youngsters who lived over the past ice age.