Dig in northern Kansas reveals human artifacts

Along the Big Blue River in northern Kansas this summer, scientists with trowels and putty knives will scrape soil off the ground a few grains at a time, hoping to uncover more clues about one of the great mysteries of ancient human history.

Rolfe Mandel, a geoarchaeologist and an expert on ancient Americans, thinks a dig team he led in Pottawatomie County last summer may have accidentally uncovered human artifacts 14,000 years old or older.

If more digging and more testing show that the artifacts are really that old, that would place the site in the last Ice Age, possibly making it one of the older sites of human activity in North America.

Beyond that, identifying artifacts that old would be important because it would add to the evidence that could undermine a theory long held — but more recently debated — by many scientists: that the First Americans, as some scientists call them, walked into North America from Siberia, and that they took that hike sometime after about 13,500 years ago.

Gathering evidence

Mandel's team was digging with a backhoe along the Big Blue, studying a site of Native American activity dating back to 5,000 years, when they found something older.

When they dug a trench about 4 feet below the surface, they found one flint flake, and then more. They were embedded in a cluster in a geologic deposit called the Severance Formation, a deposit that Mandel knew is 14,000 years old or older.

They found at least one hand-made stone scraping tool, and "at least a dozen pieces of chert and a fire-cracked rock," Mandel said last week. "A cluster of artifacts, well down in the Pleistocene (ice age) sediments was very intriguing."

That site along the river, though it has changed in 14 millennia, would have been ideal for Ice Age hunters, Mandel said.

"Lots of nearby springs, lots of lithic (stone) resources," he said. "Lots of wildlife."

Those First Americans, if they were here then, were hunting mammoths and mastodons, camels, horses and extinct Ice Age bison, much larger than today's bison, with long horns.

Scientists have long thought the First Americans crossed from Siberia. They think the crossing occurred at or after 13,500 years ago because they know that giant, impassable glaciers from the last ice age covered Alaska for many thousands of years, until about 13,500 years ago.

That period, and that theory, has come under increasing scrutiny in recent years, said Michael Waters, director of the Center for the Study of the First Americans, based at Texas A&M University.

For years now, other scientists have found tantalizing — but not entirely conclusive — evidence that people were living off the land thousands of years before the Alaskan glacial corridor opened.

Scientists, including Waters and Mandel, have studied or found what they believe might be sites of human activity older than 13,500 years. One site, identified by Mandel near Kanorado, Kan., several years ago, is possibly more than 12,000 years old.

One site, called Monte Verde, is located in Chile at the far south end of South America and is dated at older than 14,000 years.

There are two sites in Wisconsin containing the bones of mammoths and the flint tools of humans, firmly dated to about 14,500 years old, Waters said.

None of this is conclusive yet, but increasingly, Waters said, scientists are pondering whether the First Americans came to America by boat, migrating slowly, hunting seals at the edges of the vast Ice Age glaciers, paddling away from Siberia and along the coasts of Alaska and Canada, carrying grandmothers and children and dogs with them.

Eventually, Waters said, they would have reached rich greenery and resource-rich inlets like that of the Columbia River and would have begun to colonize.

More digging needed

In Pottawatomie County near the Blue River last summer, Mandel and other scientists were digging a trench with a backhoe while studying a 5,000-year-old site of Native American artifacts when Mandel noticed something much deeper in the trench; a flake of chert, the sort of sharp, jagged debris left behind by Native American hunters knapping spear points and knife blades out of flint cores.

"One flake did not impress me," he said. But then he found more, in a cluster.

Finding human artifacts like that in 14,000-year-old soil is not conclusive, Mandel said; rocks can fall into older layers through the cracks of sun-dried soil; or packrats or burrowing animals can sometimes move artifacts into deeper layers.

"But this was a cluster," Mandel said, ''And that is intriguing."

Mandel was not able to do much digging on the site last summer, which is why he wants to bring in researchers from the Odyssey Research program that he runs for the Kansas Geological Survey.

This is not the first time Mandel has found possible clues to the most ancient American hunters. In Sherman County, near Kanorado, Mandel earlier this decade had led archaeological teams that found what until now was probably the oldest known site of human activity in Kansas, and among the oldest in North America.

Among ancient animal bones eroding out of a dry western Kansas creek bank, they found mammoth bone and stone-tool flint lying next to each other in soil dating from 13,000 years ago.

Below that, they found something even more tantalizing: mammoth and camel bone, fractured in a way that the archaeologists say can be caused only when people shatter bone with stone to make flaked bone tools, or to get at the nutritious marrow. The older bones date at 14,200 to 14,400 years ago.

The ancient Americans, Mandel said, were nomadic hunter-gatherers; they were thoroughly modern human beings, like us, but they had not yet invented agriculture, the domestication of animals, settled villages, pottery or the bow and arrow.

They made their living by walking — following the migrating herds of elephant, camel, bison and other animals; and they supplemented this by digging up things like cattail roots (starch), wild onions (vitamin C) and freshwater mussels (protein and vitamins).

Finding evidence of these most ancient of Americans can be difficult, however. Unlike their descendants, they left behind no large trash pits filled with cultural artifacts; they built no houses, created no pottery. All they left that lasted are the spear points and a few other stone tools.

This story was originally published March 31, 2010 at 12:00 AM with the headline "Dig in northern Kansas reveals human artifacts."