10,000 years ago, a band of nomadic hunters stampeded 600 bison off the edge of a small cliff then speared and butchered the beasts before hauling off the meat. Or maybe not. Maybe, instead, a lightning bolt or a swift-moving grass fire killed the whole herd, and their remains were quickly buried beneath wind-blown sand and silt. A few decades later, hunters camped on the buried bison remains, leaving behind stone spear points and tools that, over the millennia, have mixed with the animal bones. Those conflicting interpretations confronted University of Colorado archaeology students last month at the Hudson-Meng Bison Kill on the Oglala National Grassland, about 330 miles northeast of Denver (Colorado, USA).
     The bones were discovered in 1954, and the dispute still rages. Archaeologist Mark Muniz, who supervised CU students digging two exploratory trenches near the southern edge of the bone layer, called the Hudson-Meng dispute "a major controversy among archaeologists that has received very little press."
     The original 1970s excavator of the site, Larry Agenbroad, took over management of Hudson-Meng from the U.S. Forest Service in May. A vocal defender of the stampede-'em- and-spear-'em interpretation, he renamed the site to include the words "Bison Kill" and removed five interpretive signs presenting the opposing theory. On the other side of the debate are Colorado State University archaeologist Lawrence Todd and Iowa State University archaeologist David Rapson. "I'm not surprised," Rapson said when told that Agenbroad had removed interpretive signs from the Hudson-Meng visitor center. "Agenbroad is very strongly committed to his position and is making a substantial investment to interpret the site the way he wants it interpreted," Rapson said. "But we always tried to present both sides, rather than just giving visitors one interpretation."
     A bulldozer uncovered the Hudson-Meng bones in 1954. In October 1971, Agenbroad led the first formal excavation of the site. On the first day of the dig, a 6-inch stone spear point was found protruding from beneath bison ribs in one of the trenches. It was made of brown flint, and its distinctive tapered shape defined it as an Alberta Culture spear point. Alberta Culture big-game hunters roamed from the Canadian prairie provinces to northern Colorado about 10,000 years ago. Twenty-one other partial or whole Alberta points have been found at the bison-bone site, along with stone butchering tools and more than 3,500 small stone 'waste flakes' produced during the tool-making process. Radiocarbon dating showed that the bison bones are about 10,000 years old. Agenbroad concluded that Alberta Culture hunters stampeded the bison off a small cliff then finished them off with spears.
     The site became known as the Hudson-Meng Bison Kill and the name stuck until 1991, when the U.S. Forest Service funded new research at the site by Todd and Rapson. The new team concluded that most of the spear points and other stone tools had been recovered about two inches above the main bone layer. They soon became convinced that Hudson-Meng held the story of two distinct, unrelated events: the sudden death of hundreds of bison, followed a few decades later by the arrival of Alberta Culture hunters who occupied the site and left behind spear points and tools.
     Todd and Rapson convinced the Forest Service to rename the site the Hudson-Meng Bison Bonebed, a label that describes the remains without speculating about how they got there. The new name lasted until Agenbroad took over in May. Now every T-shirt, coffee mug, refrigerator magnet, baseball cap and necklace in the gift shop is stamped "Hudson-Meng Bison Kill."
     While rejecting Agenbroad's interpretation, Rapson admits that he and Todd can't say with any confidence what killed the bison."This dispute will go on for years and will be seriously, acrimoniously debated," he said. The outcome could alter archaeologists' views about the capabilities of early Paleoindian hunters, who roamed the Americas more than 6,000 years ago.
     "Hudson-Meng has been a very curious outlier from the main pattern of Paleoindian behavior," Rapson said. "This has always been considered the earliest example of a bison jump site with a huge number of animals killed." Most of the oldest North American bison 'jumps,' places where ancient hunters drove herds over cliffs to kill them, date to 4,000 or 5,000 years ago, he said. If Agenbroad is right, then the 10,000-year-old Hudson-Meng site represents an "anomalous and unique" find, he said. Agenbroad disagreed. He said there's an equally old bison jump site in Texas.

Source: Rocky Mountain News (4 July 2006)