Jeff Dilyard squatted in a waist-deep pit beneath a rock overhang, contemplating a dark patch of sand he uncovered. Perhaps it's the remnants of a campfire an Indian hunting party built more than 10,000 years ago. It was just a few feet away that the retired teacher and volunteer archaeologist found the base of a Paleo-Indian hunter's spear point this summer. Excavations such as this one help prove that the natural rock overhangs that dot Ohio's landscape (USA) provided shelter for hunters dating back more than 12,000 years.
     This all makes perfect sense to Nigel Brush. Brush, a geology professor at Ashland University, has spent 27 years leading excavations at 30 rock shelters in Ohio, mostly in Holmes and Coshocton counties. In 1983 he found projectile points from several prehistoric periods as well as flint flakes beneath a sandstone outcropping near to his family's farm in Coshocton County. That indicated people had crafted their weapons there. But how far back did ancient Indians use these sites? A year later, at another rock shelter site in northwestern Coshocton County, Brush found his first evidence. He sent charcoal from a sandstone-lined hearth he uncovered about 3 feet beneath the surface back to UCLA for carbon dating. It was 12,185 years old, making it one of the oldest signs of humans in Ohio. On the way down, he'd found tools, weapon points, pottery pieces, flint flakes and animal bone fragments that showed habitation during every period of prehistory.
     "We were thinking that as you went down level by level, the use might change," he said. "Surprisingly, we found the shelters were used over and over again the same way for thousands of years." Some were base camps that might have been used for months. He finds thousands of flint chips, bone fragments and other signs of long-term habitation in those. Others appear to have hunting camps, used for a few weeks at a time with fires and smaller flint flakes that showed that the Indians finished points there, but did their primary knapping somewhere else. Still others appear to have been inhabited intermittently, some for a night or two, others for a few hours as shelter from a storm and still others for a few minutes as a place to stash a piece of flint or a pot for later use. They're usually the smallest and show the fewest signs of habitation.
     Jeff Dilyard's find helped link some of the clues. Dilyard, a volunteer for 24 years, is a member of a consortium of geologists and archaeologists from Ashland, Wooster and Columbus. Last month he had worked his way down to what appeared to be an unpromising layer of sand on the last excavation before Brush was going to start compiling his research for a book. He was going to quit there when he found it: a chip of brown flint. The flint piece was worked into a concave arc on one side and was broken off flat on the opposite. It has vertical grooves, or flutes, worked into it. Dilyard knew it was old. But he didn't know just how old until experts had a look at it.The tips, Brush said, all look pretty much the same. It's the base of a flint spear point that tells archaeologists who made it. But those vertical flutes tell them that Paleo-Indians made the one Dilyard dug up in Coshocton County. Brad Lepper, an archaeologist with the Ohio Historical Society, examined the find. He said the point likely is older than 10,000 years.
     Dilyard now is looking for further evidence of ice-age people using the rock shelter. The dark sand he's uncovered might be a clue. He consults with Nick Kardulias, an College of Wooster archaeologist. "It looks like it's in a pristine situation," Kardulias said. "This looks real. Would I call it a hearth? I don't know." Dilyard agrees that it bears more investigation. "We're going to take some carbon and have it tested," he said. "If it is, it'll be pretty cool."

Source: The Columbus Dispatch (20 September 2009)