Ancient tools found in Alaska may shed light on how humans first arrived in America, a new study finds.
The items, which include items related to making stone tools and ochera red mineral often used in ceremonies, is about 600 years older than similar objects from the Clovis people who lived further south, in New Mexico and elsewhere.
Based on stone objects up to 13,400 years oldfor most of the 20th century, archaeologists suggested that ancestors of the prehistoric culture called Clovis were among the first to migrate from Asia to the Americas. Researchers have discovered Clovis artifacts — such as distinctive, pointed stone tools — across the Great Plains and Rocky Mountains. (But research in recent decades has revealed that Clovis was far from it the first people to reach the Americas.)
It is still uncertain how the predecessors of Clovis made it to the New World. It was long believed that they reached North America via the Bering Land Bridge, which appeared when sea levels fell below last ice age (2.6 million to 11,700 years ago). These migrants could have gone over this expanse of land and then south through an ice-free corridor to give rise to Clovis.
However other work raises the question of the corridor through what is now Canada was actually ice-free when the ancestors of Clovis may have been able to cross it. Therefore, a competing idea suggests that they migrated to the New World through other routesfor example, in jet skis along the coasts of Asia, the Bering Land Bridge and America.
Alaska Archaeology
To investigate this mystery, researchers analyzed finds from the Tanana Valley in central Alaska. For more than four decades, excavations there have uncovered artifacts from early Alaskan hunters woolly mammoths and other “megafauna” or giant beasts.
The researchers focused on recent finds from the Holzman site in the middle of the Tanana Valley, where they found evidence of stone and mammoth ivory tool production dating to ca. 14,000 years agofor example, an almost complete mammoth tusk, which could have been raw material for ivory production, and a hammerstone for making stone tools. This makes this pre-Clovis site one of those earliest known human sites in the Americas.
“What is exceptional (about this site) is its remarkable preservation,” study co-author Kathryn Krasinskian archaeologist at Adelphi University in New York, told LiveScience. “The lower components tend to be frozen for much of the year, so we’ve also reclaimed old plant DNA and even a strand of 13,600-year-old bison hair. This type of preservation of organic matter is quite rare.”
The Tanana Valley lay between the Bering Land Bridge and the Ice-Free Corridor, the researchers noted, and the ivory tools and the process of producing them at the Holzman site are similar to those used for Clovis artifacts found further south.
“People lived and thrived in interior Alaska about 1,000 years before Clovis technology appeared further south,” study co-author Brian Wygalan archaeologist at Adelphi University, told LiveScience. “We argue that the growing evidence from interior Alaska confirms an inland route through an ice-free corridor as the most likely scenario for the first arrival of humans in mid-continental North America.”
In other words, the ancestors of Clovis may have first migrated across the Bering Land Bridge from Asia to Alaska, then migrated further south down an ice-free corridor to give rise to Clovis.
The evidence from Holzman and elsewhere in that area of Alaska is consistent with “migration to the continental United States via an interior route,” Todd Surovella professor of anthropology at the University of Wyoming who was not involved in the study, told LiveScience. “The evidence of ivory working provides a nice cultural link to the Clovis tradition further south.”
Hard to know
However Jack Ivesa professor emeritus of anthropology at the University of Alberta who was not involved in this research cautioned that the people of ancient northeast Asia where migrants to the Americas likely came from shared many features, such as the symbolic use of ocher in burials and similar stone objects. This raises the question of whether the ivory artifacts seen at Holzman and elsewhere are directly related to Clovis, or whether “they were part of a broader package of ideas for different populations entering the Western Hemisphere,” Ives told LiveScience.
Ives also noted that scholars often portray the inland and coastal scenarios of migration to the Americas as competing ideas “where either one or the other tells the whole story.” But a better way to go about it, he said, “is to realize that if we want to have a comprehensive picture of this early time frame, we need to understand what’s going on in both the early period coastal and (ice-free) corridor worlds.” Geneticists often suggest that the people of the New World involved successive episodes of small founding generaso both the inland and coastal scenarios may have played a role, Ives added.
Wygal and his colleagues aim to continue excavations in the Tanana Valley to learn more about how the first Alaskans interacted with woolly mammoths and other aspects of their environment, he said. Future research should also examine “the ice-free corridor itself,” Surovell said. “There has been a lot of research on coastal areas, but the ice-free corridor, on the other hand, has been largely neglected.”
The researchers described their findings in the February 15 issue of the journal Quaternary International.
Wygal, BT, Krasinski, KE, Barber, L., Holmes, CE, & Crass, BA (2025). Stone and mammoth ivory tool production, circulation, and human dispersal in the middle Tanana Valley, Alaska: Implications for the Pleistocene peoples of the Americas. Quaternary International, 755, 110087. https://doi.org/10.1016/j.quaint.2025.110087
