It’s one of the greatest mysteries of our time. But archaeologists and even geneticists are closer than ever to understanding when humans made the first bold journey to the Americas
In recent years, however, that version of events has taken a beating, not least because of the discovery of archaeological sites in North and South America showing that humans had been on the continent 1,000 or even 2,000 years before the supposed first migration. A subsequent theory, known as the “Kelp Highway,” came closer to the mark: As the massive ice sheets covering western North America retreated, the first humans arrived on the continent not only by foot but by boat, traveling down the Pacific shore and subsisting on abundant coastal resources. Supporting that idea are archaeological sites along the West Coast of North America that date back 14,000 to 15,000 years.
Left, Paleolithic evidence: a modified carnivore tooth from the Yana River in Siberia; a spear point from Quadra Island; a stone flake found on the island, at Yeatman Bay. Right, Louie Wilson (in hat), an archaeologist and member of the We Wai Kai nation, works with graduate students from the University of Victoria to record data on Quadra Island, British Columbia. (Pavel Ivanov; Rafal Gerszak; Al Mackie (2))
Now our understanding of when people reached the Americas—and where they came from—is expanding dramatically. The emerging picture suggests that humans may have arrived in North America at least 20,000 years ago—some 5,000 years earlier than has been commonly believed. And new research raises the possibility of an intermediate settlement of hundreds or thousands of people who spread out over the wild lands stretching between North America and Asia.
The heart of that territory has long since been submerged by the Pacific Ocean, forming the present-day Bering Strait. But some 25,000 to 15,000 years ago, the strait itself and a continent-size expanse flanking it were high and dry. That vanished world is called Beringia, and the developing theory about its pivotal role in the populating of North America is known as the Beringian Standstill hypothesis—“standstill” because generations of people migrating from the East might have settled there before moving on to North America.
Much of this new theorizing is driven not by archaeologists wielding shovels but by evolutionary geneticists taking DNA samples from some of the oldest human remains in the Americas, and from even older ones in Asia. Those discoveries have opened a wide gap between what the genetics seem to be saying and what the archaeology actually shows. Humans may have been on both sides of the Bering Land Bridge some 20,000 years ago. But skeptical archaeologists say they will not believe in this grand idea until they hold the relevant artifacts in their hands, pointing out that no confirmed North American archaeological sites older than 15,000 to 16,000 years currently exist. But other archaeologists are confident it is only a matter of time until older sites are discovered in the sprawling, sparsely populated lands of eastern Siberia, Alaska and northwestern Canada.
Dig sites near the coastline on Quadra Island, where sea levels 14,300 years ago were about 650 feet above modern-day levels. By 12,000 years ago, they were within ten feet of today’s. (5W Infographics; Map Sources: Hakai Institute, University of Victoria, Daryl Fedje, Keith Holmes)
It’s an exciting, if at times esoteric, debate, touching on basic questions we’re all connected to, such as why people first came to the Americas and how they managed to survive. Yet no matter when or how they made the trek, the coast of what is now Canada was on their itinerary. And that’s what brought me to British Columbia to meet up with a group of anthropologists who have discovered important signs of ancient life along the Pacific.
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The rugged shoreline of British Columbia is carved by countless coves and inlets and dotted with tens of thousands of islands. On a cool August morning, I arrived on Quadra Island, about 100 miles northwest of Vancouver, to join a group of researchers from the University of Victoria and the nonprofit Hakai Institute. Led by anthropologist Daryl Fedje, the team also included his colleagues Duncan McLaren and Quentin Mackie, as well as Christine Roberts, a representative of the Wei Wai Kum First Nation.
The site was located on a tranquil cove whose shores were thick with hemlock and cedar. When I arrived, the team was just finishing several days of digging, the latest in a series of excavations along the British Columbia coast that had unearthed artifacts from as far back as 14,000 years ago—among the oldest in North America.
On a cobble beach and in a nearby forest pit that was about six feet deep and four feet square, Fedje and his colleagues had discovered more than 1,200 artifacts, mostly stone flakes, a few as old as 12,800 years. All testified to a rich maritime-adapted culture: rock scrapers, spear points, simple flake knives, gravers and goose egg-size stones used as hammers. Fedje reckoned that the cove site was most likely a base camp that was ideally situated to exploit the fish, waterfowl, shellfish and marine mammals from the frigid sea.
Read more of this long story at: https://www.smithsonianmag.com/science-nature/how-humans-came-to-americas-180973739/
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