Fossil footprints show humans in North America more than 21,000 years ago

Fossil footprints show humans in North America more than 21,000 years ago

The footprints, the earliest proof of humans in the Americas, indicate that people must have arrived before the last Ice Age.

When he first went to White Sands National Park in New Mexico to work as a wildlife scientist in 2005, Dan Bustos learned about the “ghost tracks.” When the ground was damp enough at specific times of the year, ghostly footprints would appear on the otherwise flat earth before disappearing when it dried out.

It wasn’t until 2016 that scientists proved that the phantom tracks were made by real people, and it’s only now that some of White Sands’ ancient footprints have been dated as the continent’s oldest.

“We’d been suspicious of the age for a while, and now we’ve confirmed it. It’s fantastic to know that there are mammoth prints a meter or so above the human footprints in the layers, since it just adds to the narrative.” “It’s exciting,” Bustos added.

The footprints at White Sands were dated by analyzing the seeds of an aquatic plant that formerly grew along the banks of the dried-up lake, Ruppia cirrhosa, better known as ditchgrass. According to research published Thursday in the journal Science and co-authored by Bustos, ancient ditchgrass seeds were discovered in layers of hard earth both above and below numerous human traces at the site, and they were radiocarbon-dated to estimate their age.

Trails of footprints called "ghost tracks" have been seen in the White Sands area for years, but usually only when the ground was wet.