Spear tips point to path of first Americans

VANCOUVER, CANADA—For years archaeologists have searched for a sign of the earliest Americans—the mysterious newcomers who, it’s generally believed, set out from Asia and spread down the Pacific coast by boat more than 14,000 years ago. Last week, at a jammed session of the meeting of the Society for American Archaeologists here, researchers proposed that such evidence has been under their noses all along. They argued that a staple of museum collections known as western stemmed points—roughly pinkie-sized stone spearpoints with a chunky stem—are the handiwork of those first arrivals.

The western stemmed tradition “is finally coming into its own,” says Michael Waters, an archaeologist at Texas A&M University in College Station. Stemmed points—which have been found up and down the Pacific coast and across the western United States—and the methods associated with making them appear to be coalescing into “an ancient coastal tradition,” says Quentin Mackie, an archaeologist at the University of Victoria in Canada.

Archaeologists once thought the so-called Clovis people were the first in the Americas. These big game hunters spread their Clovis spearpoints—long and thin with distinctive hollows carved into both sides of the base—across the United States and northern Mexico starting about 13,000 years ago, when they arrived via an ice-free corridor through glacier-covered Alaska and western Canada.

But then scientists discovered human occupation as far south as Chile dated to before 14,000 years ago—before the ice-free corridor even opened. The Clovis-first model collapsed in favor of a fuzzy picture of coastal migrants. But direct evidence of their presence remains elusive.

Western stemmed points were once considered cruder, later cousins of the larger and more sophisticated Clovis points. But an early hint that some stemmed points might be older emerged in 2012, when a team reported 11,300-year-old examples in Oregon’s Paisley Caves. That made them as old as any Clovis points in this region, and maybe older. Archaeologist Dennis Jenkins of the University of Oregon in Eugene, the first author of that paper, later found western stemmed points buried even deeper in the cave, in layers he thinks are more than 14,000 years old. He’s waiting for radiocarbon dates.

The stone detritus the pointmakers left behind is now adding to the evidence that western stemmed points arrived first. To make one, you knock off the top of a round stone, creating a flat surface. Then you strike that surface to chip off sharp flakes, and finish the job by carving the base of a flake into the telltale chunky stem. As a pointmaker popped off more and more flakes, the remaining stone took on a distinctive shape: a “discoidal core” that looks nothing like the relics of Clovis pointmaking, in which blades are stripped off from the sides of a stone. So it’s unlikely that Clovis could be the precursor of this technology, researchers say. “The garbage left behind by these two technologies is radically different,” Jenkins says.

Spear hunt version="1.0" encoding="utf-8"? Location of stemmed points Human occupation Ushki Lake ~ 13,000 Lower Amazon ~ 12,500­±500 Quebrada Jaguay ~ 12,000­ Paiján ~ 12,400­ Incipient Jōmon ~ 15,500­ Buhl ~ 12,500­ Channel Islands ~12,000­ Paisley Caves ~ 11,300 Haida Gwaii ~ 12,700 Isla Cedros ~ 12,500 Monte Verde >14,000 Credits: (Graphic) J. You/Science; (Data) J. Erlandson et al., Quarternary International 239. 1-2, (1 July 2011) © Elsevier

Archaeologists are finding discoidal cores all along the Pacific coast—the putative migration route for the first Americans. They also find points with stemmed bases of various styles, and half-moon flakes perfect for opening shellfish. “It’s a package we’re finding as far down as South America,” Mackie says.

At the crowded symposium, archaeologist Daryl Fedje of the University of Victoria presented evidence of stemmed points and discoidal cores on the island of Haida Gwaii in British Columbia, Canada, dating back at least 12,700 years. The cores are also present at a site on nearby Triquet Island occupied 14,000 years ago, Fedje said. While he spoke, two archaeologists in the audience high-fived: Matthew Des Lauriers of California State University in Northridge and Loren Davis of Oregon State University in Corvallis had found a similar collection of discoidal-method artifacts 3000 kilometers away on Isla Cedros, an island off the Pacific coast of Baja California, where radiocarbon dates put human occupation back to almost 13,000 years ago.

To Des Lauriers, the findings suggest that “there’s a similar mindset” among early coastal dwellers from Tierra del Fuego in Argentina to British Columbia. If so, they likely shared the same ancestral culture, he says.

Some researchers are already daring to draw connections with Asia. In his talk, Fedje said his cores and points “would fit perfectly well” into collections of Siberian artifacts. Todd Braje, an archaeologist at San Diego State University in California, sees similarities in various styles of stemmed points around the Pacific rim from Japan to Peru (see map).

But even enthusiasts like Braje admit that “there are still huge gaps in the data.” No stemmed points in the Americas have yet been solidly dated to 14,000 years ago. A talk by Idaho State Archaeologist Kenneth Reid in Boise noted the scarcity of confirmed radiocarbon dates on the points from his region and pointed out the dangers of relying on stratigraphy alone. Rock-solid radiocarbon dates around the Pacific will be required to prove that stemmed points represent a coherent coastal culture, archaeologists say.

Mackie suspects an untold number of stemmed points and discoidal cores are already sitting in museum collections, just waiting to be recognized as part of the same coastal tradition. “You can only find what you’re looking for,” he says. And nobody was looking—until now.