On the 23rd local time, a research report showed that fossil footprints of ancient humans were found in New Mexico, about 23,000 years ago.
According to media reports, as early as 2009, David Bustos, a resource program manager at White Sands National Park in the United States, found the first footprint in ancient wetlands. Over the years, he and other researchers have found more footprints in the park. Scientists at the U.S. Geological Survey recently analyzed seeds stuck in footprints to determine their approximate age, which is about 22,800 to 21,130 years old.
(Undated photos provided by the National Park Service in September 2021 show fossil footprints of humans in White Sands National Park, New Mexico.)
The findings could shed light on a long-held mystery that has intrigued scientists: When did humans first reach the Americas after dispersing from Africa and Asia? In response, most scientists believe that ancient migration connected Asia to Alaska through a now-submerged land bridge. Based on a variety of evidence — including stone tools, fossil bones and genetic analysis — other researchers speculate that humans arrived in the Americas about 13,000 to 26,000 years ago or earlier.
The report says the current study provides more reliable clues for humans to determine when to arrive in North America. They wrote in the journal Science, which published the study Thursday, that fossil footprints are more indisputable and direct evidence than "artifacts, improved bones or other more traditional fossils." "What we're presenting here is evidence of a time and place."
Based on the size of the footprints, the researchers believe that at least some of the footprints were left by children and adolescents who lived during the last ice age. "We knew they were old, but we couldn't determine the age of those footprints until we found seeds on them," Bustos said Thursday. The footprints, made of fine silt and clay, are fragile, so researchers must quickly collect samples. "The only way we can save them is to document them — take a lot of photos and make 3D models."
Fossil footprints of saber-toothed cats, dire wolves, Colombian mammoths and other ice age animals have also been found in earlier excavations in White Sands National Park.
Wuhan Morning Post intern reporter: Chen Mengting