Human evolution: new age for White Sands foot prints (Introduction)

by David Turell , Thursday, June 19, 2025, 00:35 (9 days ago) @ David Turell

23,000 years old:

https://www.livescience.com/archaeology/evidence-is-building-that-people-were-in-the-am...

"The age of "rarely preserved" ancient human footprints dotting the landscape at White Sands National Park in New Mexico has been hotly debated for years. Now, a new study has found that these footprints really are around 23,000 years old — but the date isn't accepted by everyone.

"If the 23,000-year-old age is accurate, it would mean that humans were in North America around the peak of the Last Glacial Maximum, the coldest part of the last ice age — far earlier than archaeologists had previously thought.

"In the new study, the researchers radiocarbon-dated organic sediment in core samples from the site, which provided dates for the footprints as well as for the entire paleolake and river system that once existed there. The analysis was done in labs unaffiliated with earlier studies.

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"The saga of dating the roughly 60 footprints goes back to 2021, when a study reported the discovery of the footprints and dated them to between 21,000 and 23,000 years old. However, a 2022 rebuttal took issue with using the seeds of ditch grass (Ruppia cirrhosa), a water plant, for radiocarbon dating. Water plants get their carbon from underwater, which can be much older than carbon from the atmosphere. This can skew the levels of carbon 14, a radioactive version of the atom, in the samples, making the plants appear older than they really are.

"So, in 2023, researchers redated the site with optically stimulated luminescence (OSL) dating, which revealed when quartz or feldspar grains in the tracks were last exposed to sunlight, and radiocarbon dating of ancient conifer pollen from the footprint layer — which proved to be another way to use carbon 14 without relying on water plants.

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"Now, the new study offers more evidence that the footprints date to the Last Glacial Maximum, when the area was a vast wetland inhabited by ice age animals. The footprints likely came from hunter-gatherers who arrived in the Americas after traveling along the Bering Land Bridge, which connected Siberia and Alaska when sea levels were lower, research suggests.

"For decades, researchers thought the earliest Americans were the Clovis, who lived in North America around 13,000 years ago. But the footprint discovery and others are slowly revealing that Indigenous people reached the Americas much earlier than thought.

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"When added together, there are now a total of 55 radiocarbon-dated samples of mud, seeds and pollen from the footprint layer that support the 21,000- to 23,000-year-old dates, Holliday said."

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Comment: There have been Central and South American findings that human were there in the same time frame.