IBC2000-1  Archaeology

Prehistoric Human and Bison Relationships on the Plains of North America

George C. Frison, Emeritus Professor
Member, U.S. National Academy Of Sciences
Department of Anthropology
PO Box 3431, Room 123, Anthropology Building
University of Wyoming
Laramie, WY USA  82071-5136

 

The following article was originally presented at the International Bison Conference in Edmonton, Alberta in August 2000.  The conference covered a wide array of bison topics including production, marketing, genetics, history and much more.  This article has been reprinted with the permission of the IBC2000 Chairman.

Extinct sub-species of bison survived the extinction period of the Late Pleistocene between about 12,000 and 11,000 years ago and subsequently became the major food source of Native Americans living on the Plains and in the Rocky Mountains. These animals, Bison occidentalis and Bison antiquus were larger than the present-day bison. Most of what we know of the physiology of these bison comes from locations where several animals were killed at one time and the geologic conditions were such that the skeletal remains were interred intact and remained undisturbed until exhumed by archaeologists.  Besides these large multiple-animal kills involving large numbers of hunters, there was day-to-day hunting of single and small groups of animals. However, the large kills of animals at a single point in time provide windows of opportunity to study populations of animals no longer present.

Climatic conditions gradually worsened beginning between about 11,000 and 10,000 years ago. This is believed to have resulted also in deteriorating feed conditions and, through selective processes, a gradual reduction in size of the bison. Bison 6,500 years ago were smaller than those 10,000 years ago but still larger than those at present which appeared around 5,000 years ago. Changes is size through time can be documented through measurements of weight-bearing skeletal elements. However, the most noticeable changes can be seen in horn core sizes (Fig. 1). Whether or not the older bison demonstrated the same behavior characteristics as the present day animals is an open question.

The oldest, well-documented bison kills by pedestrian human hunters in North America date to about 11,000 years ago. These, and more recent hunters, utilized natural features such as steep-sided arroyos with perpendicular head cuts, parabolic sand dunes, and geologic slump scars to trap and/or impede the progress of the animals long enough that some could be killed. They were also constructing corrals and modifying natural features to improve their efficiency. By 5,000 years ago and probably earlier, stampeding animals over perpendicular bluffs and into karsts or large sinkholes became a common method of killing large numbers of animals at one time. Some jump-offs were high enough to kill large numbers of animals outright, while others were low and required corrals at the base of the cliff to hold the animals until they could be killed.

There are some early historic accounts that reveal important aspects of bison behavior. Hunters on foot had to carefully maneuver bison herds into the proper position in order to stampede them over a cliff or drive them into a corral or trap. Long lines of stone piles or drivelines leading to jump-offs and traps are common features. Originally, they had brush and other perishable materials added to increase visibility. They were not designed to serve as fences but their presence tended to keep a herd moving between them. Other reports describe the stone and brush piles near the jump-offs or trap entrances large enough to conceal persons that would reveal themselves at the proper moment to encourage the headlong flight of the animals during the critical moments of the final stampede.  Still other reports describe decoys, persons wearing bison hides, exploiting the curiosity of the animals that under certain conditions could lead herds in the direction of a jump or trap.

Bison have a keen sense of smell and careful observations of wind conditions allowed the hunters to utilize human scent to move a herd but not induce headlong flight, as would have been the result of revealing themselves and attempting to drive the animals. However, by the early 18th century, the use of horses dramatically changed bison hunting so that it was no longer necessary to drive the animals over bluffs or into traps.

About three decades ago, archaeologists realized that the study of bison and other faunal remains could reveal information not only about the animals but also about the activities of the human hunters. Tooth eruption, tooth wear, fetal development, and bone ossification schedules can reveal animal ages at the time of death and confirm the time of year of animal kills. Human modifications of bones contrast sharply with carnivore and natural modification of bone through geologic processes. Knowing these facts, a bison kill places the human group in a specific location at a given time of the year. The number of animals killed and the herd structure reveals some idea of the number of hunters required and the amount of meat obtained. A surplus of meat beyond immediate requirements indicates storage for later use. Warm weather kills indicate drying of meat while cold weather events probably indicate frozen meat caches. Drying meat reduces the bulk and is portable but freezing required the human group to remain in the area to protect and utilize the resources.

There is no pictorial record of prehistoric bison hunting and most is the product of artistic renderings of those unfamiliar with animals. Prehistoric bison hunting is often depicted as having hunters wave a blanket and shout at the animals who would then jump off a cliff to their deaths. In reality a certain number of stampeding animals is required so that the mass of animals will force the lead animals over the edge. Bogging animals is another favorite artistic solution to prehistoric bison trapping. Bison come and go at will into and out of boggy areas but usually only the aged and sick become mired. A bog is also an extremely undesirable place to extract and butcher a large animal.

Bison behavior is an important element in interpreting prehistoric hunting. Both internal and exterior conditions determine their behavior. The former include sex, age, and condition; the latter include herd structure, time of year, weather, availability of feed, terrain and vegetative cover. The archaeologist has to be familiar with bison behavior and employ specialists to reconstruct conditions at the time of the kill event in order to accurately interpret past bison procurement strategies.

Ethnographic accounts of large animal procurement activities document ritual behavior in the process. The outcome of an event such as a bison drive always had a high incidence of failure and supernatural help was always sought. The archaeological record occasionally provides some evidence of this kind of religious activity. In one instance, a 2,000 year-old partially preserved wooden structure alongside a corral bears no evidence of use as a habitation or in holding the animals. However, specially placed parts of the animals including skulls and the largest hump bones (dorsal spines) is a strong indicator of shamanistic or supernatural ritual designed to help control the animals and bring them into the corral.

Prehistoric weaponry was well designed and surprisingly efficient. In the hands of an experienced hunter, the atlatl (throwing stick) and heavy dart shaft tipped with a stone projectile point easily delivers lethal wounds to large animals such as bison and even elephants. We believe the bow and arrow came into use about 2,000 years ago using smaller projectiles but at higher velocities. Besides horses, firearms also changed bison hunting in historic times.

In conclusion, bison were the main food source of prehistoric Native Americans on the Plains and Rocky Mountains. They were accomplished hunters but lacked the means of threatening bison populations with extinction. The prehistoric archaeological record yields little evidence of wanton killing of bison or extensive wasting of meat products. There was no incentive to kill more than needed at one time since storage potential was limited and surpluses could not be sold for profit. Once the immediate production goals (killing the desired number of animals) were met, production (killing more animals) ceased. This economic philosophy changed rapidly with the introduction of horses along with the influence of Europeans, their technology and trade goods. It very nearly resulted also in the extinction of the bison.   

Fig. 1. Ten thousand year-old male (a) and female (b) Bison antiquus skulls; male (c) and female (d) 6,500 year-old intermediate type bison skulls; male (e) and female (f) Bison bison or modern bison skulls. The brain cavity of one (f) was exposed by smashing the frontal bones.

Suggestions for Further Reading

Davis, L.B. 1978.  The 20th-Century commercial mining of Northern Plains bison kills. In: Bison Procurement and Utilization: A Symposium. Edited by L. B. Davis and M. Wilson, pp.   254-286. Plains Anthropologist Memoir 14.

Forbis, R.G. 1962.  The Old Women's Buffalo Jump, Alberta. National Museum of Canada Bulletin No. 180: 56-123. 

Frison, G.C. 1991.  Prehistoric Hunters of the High Plains, Second Edition. Academic Press, San Diego.

McDonald, J.N. 1981. North American Bison: Their Classification and Evolution. University of California Press.

McHugh, T. 1972.  The Time of the Buffalo. Knopf, New York.

Roe, F.G. 1951.  The North American Buffalo. University of Toronto Press.