Dig Diary: Debating the Clovis Controversy

by Adrien Hannus

In the early 1980s, I excavated a Clovis mammoth kill and butchering site in the Badlands of South Dakota. During the investigation of that site, we found evidence of tools made from flaked mammoth bones. It was a controversial finding at the time because it was the first evidence anyone had found of Clovis tools made from flaked bone. In spite of the controversial nature of that evidence, I was eventually able to solidify my research and gain support in the scientific community through additional, highly specialized studies and the participation of a number of experts in the field. This is very typical of the process that goes on in archaeology — whenever new evidence emerges that challenges our current understanding, it must go through a long process of examination, debate and further research before it can gain widespread support.

Time Team America's investigations at Topper allowed us to participate in the excavation of another controversial site. The evidence found by Dr. Al Goodyear and his team at Topper is challenging the long-held hypothesis that human groups entered the New World quite recently — perhaps as recently as 13,000 to 14,000 years ago — which is supported by archaeological evidence associated with the "Clovis" culture.

Over the course of the last 70 years, the evidence for Clovis as the earliest culture in the New World has grown strong, with solid evidence emerging from sites spread across the vastness of the American continent. The long-held "Clovis First" hypothesis suggests that humans crossed into North America at the end of the Ice Age via the Beringian "land bridge" and quickly spread across the continent.

From time to time, other archaeological sites have come to light for the suggestion that they represent pre-Clovis cultural activity. Though often intriguing, dozens of these sites have been rejected by the scientific community for their failure to produce convincing pre-Clovis cultural evidence. When new hypotheses emerge regarding when and how humans migrated to the New World, a significant scholarly process must be undertaken in order to gain widespread support. This process involves the participation of specialists from many disciplines. For example, geomorphologists study the changes in landscapes since the last Ice Age. Biologists and paleontologists study plant pollens, animal bones and mollusks in order to reconstruct ancient climates. To date, the best candidates for very early human activity on the North American continent comes from two vastly disparate sites which have been subject to intensive investigations: the Monte Verde site in Chile and the Meadowcroft rockshelter in Pennsylvania, dated between 14,000 and 18,000 years before present.

It is for this same reason that the Topper site proves so controversial. Dr. Goodyear, who directs the excavations at Topper, has suggested that a cultural deposit exists at 50,000 years before present — more than 37,000 years earlier than any widely accepted evidence, and at least 30,000 years older than even some very controversial evidence. Beyond challenging a well-established and widely-accepted theory, a collection of compelling evidence for human cultural activity in the New World 50,000 years ago would represent a dramatic shift in the way we view the human cultural past.

Finding a compelling artifact is important, but there are many other factors that must be considered in order to solidify the evidence. For example, any new hypothesis concerning the arrival of humans to the New World must be cast against the backdrop of the extreme climatic oscillations of the last Ice Age. Is it feasible for humans to have migrated during the time period in question? Over the course of 65,000 years, those events shaped the landscapes of much of the world. The warming and cooling episodes of the glacial events caused the rise and fall of sea levels by up to 400 feet. These changes caused the routes available for human migration into the New World to open and close.

Another important factor in determining when human groups may have entered the New World rests in determining when adequate numbers of people were present to establish enduring human cultural systems. Groups may have entered at various moments in the prehistoric past, but due to the rigors of existence did not succeed in having a continued presence over generations. Unsuccessful early groups may have left scant evidence of their presence. This evidence would be very difficult to identify and even more difficult to place in sequence with later cultural material.

These questions and many others must first be answered before definitive conclusions can be made concerning the Topper site. An understanding of the complex climatic and geologic forces that shaped the Topper site will provide a basis for understanding the importance of the site. At present, the Topper site remains highly controversial in the archaeological community. Certainly, the debate will continue for many years to come, other early sites will come to light, and researchers will debate their validity and significance. For now, the questions of exactly when and how humans arrived to the New World continues to be debated and Clovis remains as the earliest clearly-defined and well-represented cultural group in the New World.