The ‘Clovis First’ theory is proven wrong. More confirmation shows that people didn’t arrive in America by crossing Siberia through an ice-free inland corridor created after the last ice age.
A group of scientists, including Dr. Dylan Rood and Louise Guillaume of Imperial College London’s Department of Earth Science and Engineering (ESE), led by Jorie Cark of Oregon State University, researched the “The age of the opening of the Ice-Free Corridor and implications for the peopling of the Americas.” The research published on PNAS (Proceedings of the National Academy of Sciences) concluded that the ice-free Corridor was opened only after the two ice sheets covering much of North America melted 13,800 years ago.
Dr. Dylan Rood commented on the recent findings: “We have closed the door on the ice-free Corridor. This research clarifies that the Corridor wouldn’t have been available as a migration route back when people first entered the Americas some 2,000 years earlier, putting the Clovis First theory to rest.”
Transpicuous timelines disputing the clovis first theory
Stone artifacts which date back 13,400 years, found in the neighborhoods of Clovis, New Mexico, were the basis of the Clovis First hypothesis. The artifacts were regarded as the oldest archeological items in North America; thus, believing the Clovis First hypothesis didn’t need a lot of convincing. However, further research suggests that the Americas were already populated well before the estimated origin of the artifact. The proof discovered in Cooper’s Ferry, Idaho, dates about 15,000 to 16,000 years ago.
While that’s the case, there are many uncertainties concerning the opening of the ice-free Corridor. Studies also suggest that it was open sometime around 14,000 – 15,000 years ago. Ultimately, the unreliability of having multiple years to deal with begs for better knowledge on how and when the iceberg separated.
Analyzing the Ice-corridor
To add precision to this timeline, 64 rock samples from six sites in Alberta and British Columbia in Canada along the 750-mile convergence of the two ice sheets were evaluated, focusing on where both began to disconnect.
Louise Guillaume commented on the research procedure: “We used a method known as cosmogenic nuclide exposure dating, which is a ‘rock clock’ that essentially tells us how long rocks have lain exposed on Earth’s surface – after a glacier has retreated and left them behind and uncovered, for example.”
The laboratory work which Louise Guillaume carried out yielded results that suggest parts of the ice-free corridors were open more than 15,000 years ago. However, the entire length couldn’t be opened before people started migrating to the Americas.
Speaking on the results, Dr. Dylan said: “This finding really is significant, resolving a nearly century-old debate about the migration route of ancient humans.”
Jorie Clarke, the lead researcher on the study, explained the separation pattern of the iceberg. According to her, the separation started from the southern section about 15,400 ago, and then the north, leaving the middle blocked until the complete disjunction. “Similar to a zipper being opened from the bottom first, and then unzipping from the top. These results clearly establish that the ice-free Corridor was not available for the first people of the Americas.” She said.
Granted that, it is improbable that America was populated through the ice-free Corridor that spans Alaska, Yukon, and the Great Plains. However, realistic scenarios suggest that early migrants arrived in North America through the Pacific Coast.
This recent finding is also supported by earlier studies (2016) on the “Postglacial viability and colonization in North America’s ice-free corridor” published on Nature.