Matthew Des Lauriers got the first inkling that he had stumbled on something special when he pulled over on a dirt road here, seeking a place for his team to use the bathroom. While wait- ing for everyone to return to the car, Des Lauriers, then a gradu- ate student at the University of
California, Riverside, meandered across the
landscape, scanning for stone tools and shell
fragments left by the people who had lived
on the island in the past 1500 years.
As he explored, his feet crunched over
shells of large Pismo clams—bivalves that
he hadn’t seen before on the mountainous
island, 100 kilometers off the Pacific coast
of Baja California. The stone tools littering
the ground didn’t fit, either. Unlike the finely
made arrow points and razor-sharp obsidian that Des Lauriers had previously found
on the island, these jagged flakes had been
crudely knocked off of chunky beach cobbles.
“I had no idea what it meant,” says Des
Lauriers, now a professor at California State
University (Cal State) in Northridge. Curiosity piqued, he returned for a test excavation
and sent some shell and charcoal for radiocarbon dating. When Des Lauriers’s adviser
called with the results, he said, “You should
probably sit down.” The material dated from
nearly 11,000 to more than 12,000 years
ago—only a couple thousand years after the
first people reached the Americas.
That discovery, in 2004, proved to be no
anomaly; since then, Des Lauriers has dis-
covered 14 other early sites and excavated
two, pushing back the settlement of Cedros
Island to nearly 13,000 years ago. The density
of early coastal sites here “is unprecedented
in North America,” says archaeologist Loren
Davis of Oregon State University in Corvallis,
who joined the project in 2009.
The Cedros Island sites add to a small
but growing list that supports a once-heretical view of the peopling of the Americas. Whereas archaeologists once thought
that the earliest arrivals wandered into the
continent through a gap in the ice age glaciers covering Canada, most researchers today think the first inhabitants came by sea.
In this view, maritime explorers voyaged by
boat out of Beringia—the ancient land now
partially submerged under the waters of the
Bering Strait—about 16,000 years ago and
quickly moved down the Pacific coast, reaching Chile by at least 14,500 years ago.
Findings such as those on Cedros Island
bolster that picture by showing that people
were living along the coast practically as early
as anyone was in the Americas. But these sites
don’t yet prove the coastal hypothesis. Some
archaeologists argue that the first Americans
might have entered via the continental in-
terior and turned to a maritime way of life
only after they arrived. “If they came down
an interior ice-free corridor, they could have
turned right, saw the beaches of California,
and said, ‘To hell with this,’” says archaeo-
logist David Meltzer of Southern Methodist
University in Dallas, Texas.
The evidence that might settle the question has been mostly out of reach. As the glaciers melted starting about 16,500 years ago,
global sea level rose by about 120 meters,
drowning many coasts and any settlements
they held. “We are decades into the search
for coastal dispersers, and we’re still waiting for solid evidence or proof,” says Gary
Haynes, an archaeologist at the University of
Nevada in Reno, who thinks the first Americans likely took an inland route.
The hunt for that evidence is now in high
gear. A dedicated cadre of archaeologists is
searching for maritime sites dating to between 14,000 and 16,000 years ago, before
the ice-free corridor became fully passable.
They’re looking at the gateway to the Americas, along stretches of the Alaskan and Canadian coasts that were spared the post–ice age
flooding. They are even looking underwater.
And on Cedros Island, Des Lauriers is helping
fill in the picture of how early coastal people
lived and what tools they made, details that
link them to maritime cultures around the
Pacific Rim and imply that they were not
landlubbers who later turned seaward. “All
eyes are on the coast,” Meltzer says.
ON A SUNNY JUNE DAY, Des Lauriers crouches
in a gully here, bracing himself against the
wind blowing off the ocean. He leans over to
examine what could be a clue to how people
lived here 12,000 years ago: a delicate crescent of shell glinting in the sun. A few centi-
ON THE TRAIL OF
Most archaeologists think the first Americans arrived by boat.
Now, they’re beginning to prove it
By Lizzie Wade, on Cedros Island in Mexico