The first people to cross over to the Americas arrived by sea rather than a land bridge, according to a new study, according to a new study that found a giant 3,000-foot-high wall of ice blocked their path.
There have long been two main theories about how humans first migrated to North America—by way of a landmass called Beringia that once connected Asia to North America, or by traveling along the Pacific coast in small boats from Asia.
Whether they traveled to North America overland depends on whether or not Beringia actually had an ice-free corridor allowing travel down to the Great Plains.
The footprints and stone artifacts discovered by scientists suggest that the first people arrived in what is now New Mexico about 23,000 years ago, and in central Mexico 26,500 years ago.
To find out if they came by land or sea, the Oregon State University team set out to determine exactly when the ice-free corridor opened.
They found that the corridor had not been fully opened until about 13,800 years ago, with ice sheets up to 3,000 feet high where the corridor would later appear, meaning that since humans arrived over 10,000 years ago, they must have arrived by sea. .
These first migrants attempting to cross the border by land would encounter a Game of Thrones-style wall of ice that is taller than the world’s tallest building, Dubai’s Burj Khalifa, which stands at 2,722 feet, making the crossing impossible.
The first people to cross to the Americas arrived by sea, not a land bridge, and a giant 3,000-foot wall of ice blocked their path, according to a new study.
For a long time, there have been two main theories about how people first migrated to North America: through a territory called Beringia, which once connected Asia to North America, or by traveling along the Pacific coast in small boats from Asia. stock images
This study is the latest in a series of studies debunking the long-standing “Clovis First” theory, which says that humans first arrived in the Americas from Siberia via an inland ice-free corridor that formed after the last ice age.
This corridor is said to have run along the eastern front of the Rocky Mountains, but how early it opened is questionable, casting doubt on Clovis the First’s theory.
A research team led by Jori Clark of Oregon State University and including Dr. Dylan Rude and Louise Guillaume of Imperial College London found that the corridor between the two ice sheets fully opened about 13,800 years ago.
This is when the two ice sheets that covered most of North America during the last ice age melted and retreated north.
Previous studies of early stone tools found in the Americas dating back 13,400 years have led archaeologists to believe that Clovis’s people were the first migrants from Asia to North America, but this idea is widely disputed.
This roughly corresponds to the date the ice sheet corridor was discovered, but recent archaeological excavations have found remains from a much earlier period in North America.
They were from pre-Clovis civilizations: one 2021 study of 60 ancient footprints in New Mexico dated 23,000 years ago, and a 2020 study that found evidence of artifacts in central Mexico 26,500 years ago.
“Now we have strong evidence that the ice-free corridor was not open and available for the first settlement of America,” Clark said.
To find out if they came by land or sea, a team from Oregon State University and others set out to determine exactly when the ice-free corridor opened.
Clark and his team wanted to pinpoint the exit point of the ice-free corridor and examined 64 geological samples from six locations over a distance of 745 miles.
This was along a zone thought to have existed in the corridor, and included boulders that the glaciers must have carried away from their original homes.
The team looked at how long the rocks were on the surface and how long they were on the ground without ice.
“We used a method known as cosmogenic nuclide dating, which is a ‘stone clock’ that essentially tells us how long rocks have been exposed on the Earth’s surface — for example, after a glacier retreated and left them behind. and uncovered,” says Louise Guillaume.
They found that the ice-free corridor did not open properly until 13,800 years ago, with ice sheets blocking the entrance at up to 300 feet.
Clark and his team wanted to pinpoint the exit point of the ice-free corridor and examined 64 geological samples from six locations over a distance of 745 miles.
This places it later than other studies, suggesting it opened 15,000 years ago, although the team pinpointed the time when it was “fully open”.
The team isn’t saying people didn’t arrive through the corridor, it’s just that the first wave of migrants couldn’t have arrived that way.
Clarke said other waves may have taken a more direct ice-free route once the corridor opened, “but again, we need to find archaeological sites in the ice-free corridor to assess when they got off.”
Dr Dylan Rude, co-author of the study at Imperial College London, said: “We have closed the door to the ice-free corridor. This study clearly shows that the corridor was not available as a migration route back when humans first entered the Americas about 2,000 years ago, thus putting an end to the theory of Clovis the First.”
WHO WERE THE CLOVIS PEOPLE?
The Clovis people, a prehistoric group of hunter-gatherer Indians, reached North America about 13,500 years ago.
They hunted mammoths, mastodons and giant bison with large spears.
The Clovis artifacts are distinctive prehistoric stone tools, so named because they were originally found near Clovis, New Mexico in the 1920s.
They have since been identified throughout the Americas.
These early people were distinguished by the finely grooved stone points they made for weapons.
It is believed that centuries of cold, nicknamed the “Big Frost”, wiped out Clovis, as well as most of the large mammals in North America.
In recent years, however, archaeological evidence has increasingly cast doubt on the idea that these people were the first to reach the Americas.
Now, in the latest study to cast doubt on that long-standing theory, researchers led by Thomas Williams of the Department of Anthropology at Texas State University have unearthed the Gault site northwest of Austin.
They discovered many artifacts ranging in age from 16,000 to 20,000 years.