Human Migration in Alaska's National Parks: 14,000 Years of Arrivals

Adapted from an article by National Park Service archaeologist Andrew Tremayne in Alaska Park Science*, Volume 17, Issue 1, "Migration: On the Move in Alaska."*

Arctic hunters travel to a new camp near the sea. Frank and Frances Carpenter collection, Library of Congress.

Ancient Arctic and Subarctic hunter-gatherers moved camp with the seasons, usually within familiar territory, but at times people spread far from their homelands, sometimes into lands no one had lived in before. Archaeologists call such permanent long-distance moves migration, and the first arrival of people in a new area colonization. People did not simply arrive in Alaska 14,000 years ago and stay put: populations grew and declined, abandoned and resettled regions, and came and went, adapting and mixing. Archaeologists have built a detailed culture history from changing artifact styles, but many questions about who made those artifacts remain.

A timeline, by region, of Alaska's major archaeological traditions, in calendar years before present. National Park Service.

Telling migration from change

Recognizing migration in the archaeological record is difficult. Sometimes a population's tools change as it adapts in place; in northwest Alaska, people stopped making microblades and took up pottery around 3,000 years ago while keeping many other tools, suggesting one continuous population. In other cases the new artifacts bear no relation to what came before, pointing to newcomers. Such conclusions rest on comparing hundreds or thousands of sites and radiocarbon dates, together with biological evidence (skeletons, teeth and genetics) and language, which is used cautiously because languages can spread independently of peoples. On that basis, archaeologists have identified at least four major cultural transitions in Alaska over the past 14,000 years, some of them migrations and others the spread of ideas or local change.

The first people, and a return

During the Last Glacial Maximum, 24,000 to 15,000 years ago, glaciers held so much water that sea level was at least 120 meters lower than today, exposing a land bridge between Alaska and Asia. This region is called Beringia. The ice sheets cut Alaska off from the rest of North America, making it part of northeast Asia. Scientists broadly agree that people spread into Beringia during this period and from there into the Americas, but the timing and route south remain debated: through an ice-free corridor, as the traditional "Clovis-first" view holds, or earlier along the coast, where the evidence would now be under water.

Radiocarbon-dated Paleoarctic and Paleoindian sites in Alaska, about 14,000–10,000 years ago, with national parklands outlined in green. Arrows show the proposed first migration across Beringia and the back-migration of Paleoindians through the ice-free corridor about 12,000–13,000 years ago. National Park Service.

Genetics has added a new line of evidence. The Beringian Standstill hypothesis holds that the peoples of Alaska and the Americas descend from a population in Beringia that was isolated from its Asian ancestors for thousands of years before colonizing the Americas. University of Alaska Fairbanks archaeologist Ben Potter and colleagues found that ancient human DNA from the Upward Sun River site shows the first Alaskans were genetically distinct from all other Native Americans, confirming that such a Beringian population existed.

The oldest undisputed site, Swan Point in the Tanana Valley, is about 14,000 years old. Alaska's earliest culture, the Paleoarctic tradition, is marked by microblades and distinctive two-sided stone tools, as at Onion Portage in Kobuk Valley National Park; by about 12,000–8,000 years ago some of its people turned to the coast (the Paleomarine tradition). The Paleoarctic does not resemble the Paleoindian or Clovis cultures of the continental interior; its closest match is the Diuktai culture of Asia, evidence of migration from west to east across Beringia.

There is also evidence of Paleoindians in Alaska, including in Bering Land Bridge and Noatak National Preserves, with fluted and tapering-base spear points like those of the continental interior; because the fluted-point sites are about 1,000 years younger than Clovis, some researchers propose a back-migration from the south. By the end of the Pleistocene, 11,000 years ago, two distinct populations probably lived in Alaska, Paleoarctic and Paleoindian. DNA from infants buried at Upward Sun River shows the Paleoarctic people had a distinct but related genome and no living descendants in the Americas, suggesting the two groups split while Beringia was still dry land. A 10,300-year-old man from On Your Knees Cave on Prince of Wales Island in southeast Alaska, Shuká Káa, shares a genetic lineage with a Clovis skeleton from Montana and has genetic continuity with modern Northwest Coast peoples.

The Northern Archaic and the origins of Athabaskans

As the climate warmed and rising seas drowned the land bridge, Paleoarctic people adapted to regional niches and coastal habitats. Then, about 6,500–7,000 years ago, a new culture appeared, marked especially by notched dart points: the Northern Archaic tradition. Its sites are common in most of Alaska's national parklands, among them Palisades in Cape Krusenstern National Monument, Onion Portage and Agiak Lake in Gates of the Arctic National Park and Preserve.

Archaeological cultures about 5,000–7,000 years ago. Arrows show hypothetical movement of ideas or language into the existing population. National Park Service.

Whether this tradition was new people or new ideas is unknown, but the Upward Sun River DNA shows new genes entered Alaska after the Paleoarctic period, perhaps with the Northern Archaic. Many researchers see the Northern Archaic as ancestors of the Na-Dene-speaking Athabaskans. Linguistics places the origin of the Na-Dene languages in central Asia, implying a second migration from Asia, while notched points first appeared in mid-latitude North America. No Northern Archaic human remains have yet been found to settle the question.

The Arctic Small Tool tradition

About 5,000 years ago, while the Northern Archaic held the interior, a people from eastern Siberia began a migration that would eventually reach across the North American Arctic to Greenland. Their stone technology, the Arctic Small Tool tradition (ASTt), arose in the Siberian Neolithic. Dozens of ASTt sites are in Alaska's parks, especially the northern ones. At Kuzitrin Lake in Bering Land Bridge, Park Service archaeologists found an ASTt site with the oldest dates ever reported, 5450±320, and the tradition is also known at Brooks Camp in Katmai and in Lake Clark.

Archaeological cultures about 3,500–5,000 years ago, with arrows showing the proposed ASTt migration into Alaska and across the Arctic. National Park Service.

ASTt people probably crossed the Bering Strait by boat around 5,000 years ago and spread along the coasts, then over two millennia across Arctic and western Alaska, replacing Northern Archaic groups; where their sites overlap, ASTt is always younger, and there is little sign of mixing. In the Aleutians and on Kodiak, though, there is strong evidence of cultural, and probably genetic, exchange with the Paleoaleut and Ocean Bay peoples. Ancient DNA shows ASTt people and their descendants were distinct from today's Inuit and Iñupiat. As the climate changed, late ASTt people turned increasingly to the sea, giving rise to the Norton culture, which dominated coastal Alaska until about 2,000 years ago in the northwest and 1,000 years ago in the southwest. By A.D. 1000 it had vanished.

The great Thule migration

Around 2,000 years ago a new culture appeared in the Bering Strait region, the Northern Maritime tradition, known for its extensive use of ivory, elaborately engraved hunting gear and ritual objects, and near-total reliance on the sea. Its oldest sites are on St. Lawrence Island; whether it descended from the Norton people or new arrivals from Asia is unknown. By A.D. 1000 it had become the Thule tradition, the direct ancestors of the Inuit, Iñupiat and Yup'ik, genetically distinct from ASTt people.

Major archaeological traditions of the last 2,000 years, with arrows showing the proposed Thule migration, which began around A.D. 1000. National Park Service.

The Thule spread rapidly across the Arctic, from northwest Alaska south to Bristol Bay and northeast to Greenland, replacing or absorbing the late ASTt people they met. In the eastern Arctic the replacement appears complete; in Alaska, ASTt genes survive at very low frequencies. The Thule also overtook the peoples of Kodiak Island and the Gulf of Alaska coast. Important Thule sites lie in the parks, on the beach ridges of Cape Krusenstern and at Cape Espenberg in Bering Land Bridge, and Thule sites are found wherever Iñupiat and Yup'ik people live today. The Thule never went far into the interior, presumably because Athabaskan peoples held it, and this last migration set the boundaries explorers recorded from the 18th century on.

Why the parks matter

New genetic and archaeological findings are arriving faster than ever. Alaska's national parklands hold many of the key sites that define these traditions, and because the first Alaskans knew nothing of modern boundaries, what is learned in the parks illuminates the prehistory of all of Alaska.

Sources

• Andrew Tremayne, National Park Service, "A Survey of Human Migration in Alaska's National Parks through Time," Alaska Park Science 17(1). https://www.nps.gov/articles/aps-17-1-2.htm
• Key studies cited: Potter (2008, 2010), Potter et al. (2017, 2018), Moreno-Mayar et al. (2018), Tackney et al. (2015), Lindo et al. (2017), Raghavan et al. (2014), Rasmussen et al. (2010), Goebel et al. (2013), Rasic (2011), Giddings and Anderson (1986), Harritt (1998).
• The article dates the Upward Sun River burials both to 11,000 and to 11,500 years ago, so no single age is given here. It also dates Thule dominance on Kodiak to 800–700 A.D., earlier than the A.D. 1000 it gives for the Thule tradition's emergence; that date is omitted.