Fossilised footprints discovered in New Mexico indicate that early humans were walking across North America around 23,000 years ago, researchers reported Thursday.
The footprints were found during a dry lake bottom in White Sands park , first spotted in 2009 by a park manager. Scientists at the US Geological Survey recently analysed seeds stuck within the footprints to work out their approximate age, starting from around 22,800 and 21,130 years ago.
Most scientists believe ancient migration came by way of a now-submerged land bridge that connected Asia to Alaska. supported various evidence — including stone tools, fossil bones and genetic analysis — other researchers have offered a variety of possible dates for human arrival within the Americas, from 13,000 to 26,000 years ago or more.
The current study provides a more solid baseline for when humans definitely were in North America, although they might have arrived even earlier, the authors say. Fossil footprints are more indisputable and evidence than “cultural artifacts, modified bones, or other more conventional fossils,” they wrote.
What we present here is evidence of a firm time and site ,” they said.
Based on the dimensions of the footprints, researchers believe that a minimum of some were made by children and teenagers who lived during the last glacial period .
The research was published Thursday within the journal Science.
Earlier excavations in White Sands park have uncovered fossilized tracks left by a saber-toothed cat, dire wolf, Mammuthus columbi and other glacial period animals.
