Humans
PUBLISHED
The events that led to the peopling of the Americas remain shrouded in uncertainty, but researchers say that a hunter-gatherer hotspot in central Alaska may provide some clarity. Known as the Holzman archaeological site, this Ice Age camp contains mammoth ivory artifacts that resemble those created by the Clovis people, suggesting a direct link between these early Alaskan settlers and the first culture to spread across the continent.
The rest of this article is behind a paywall. Please sign in or subscribe to access the full content.Most scholars agree that the first humans to reach North America crossed over from Siberia to Alaska by navigating the frozen Bering Strait on foot. However, what happened once they arrived there is a matter of debate.
For a while, a prehistoric group called the Clovis was widely accepted to have derived from the very first people to enter the Americas. Moreover, researchers were virtually unanimous in their agreement that the Clovis reached the Great Plains by descending from Alaska via an ice-free corridor through the Rocky Mountains around 13,500 years ago.
Yet this version of events was later cast into doubt by archaeological discoveries suggesting the existence of humans in North America prior to this date. For instance, footprints at White Sands in New Mexico have been dated to more than 20,000 years ago, indicating that the Clovis were not the first Americans after all.
It was therefore proposed that the initial wave of human migration across the continent occurred via a route that followed the Pacific coast, before the ice-free corridor opened up.
However, the authors of the new study challenge this idea, arguing instead that the Clovis people were indeed the original Americans. To make their point, they highlight controversies and uncertainties regarding the supposedly older finds. For instance, they claim to be unconvinced by the age of the White Sands footprints, stating that the method by which they were dated relied on dubious signals in water stored inside ancient seagrass seeds.
Yet the bulk of their argument is centered on Alaska’s Tanana Valley, where the Holzman site is located. Extensive mammoth ivory tools and weapons found at the site indicate that Ice Age Alaskans were themselves descended from the highly specialized mammoth hunters of Siberia who first made the journey across the Bering Strait.
Dated to around 14,000 years ago, these artifacts include the earliest known ivory rods ever found in the Americas. And while the function of these items is unclear, the researchers point out that they “compare well in size, shape, and weight” with similar ivory rods found at Clovis sites across the US, most of which have been dated to around 13,000 years ago.
“Ivory working was a trait shared by Clovis-era traditions in mid-continental North America after 13.5 [thousand years ago],” write the study authors. “By assessing the evidence, it seems reasonable to conclude that the early sites in the Tanana Valley are ancestral to the Clovis tradition and their Native American descendants,” they continue.
To date, the only human skeleton ever found at a Clovis site belongs to a 12,900-year-old toddler from Anzick in Montana. Stable isotope analysis of these remains revealed that the breastfed child’s mother ate mammoth, which the study authors use as further evidence for the cultural link between the Clovis and these early Alaskan communities.
Combining all of this evidence with a lack of Ice Age sites along the Pacific Coast, the researchers contend that the first southward migration from Alaska to the Great Plains occurred via the ice-free corridor between 14 and 13 millennia ago, and that it was the ancestors of the Clovis who first undertook this journey.
The study is published in the journal Quaternary International.
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