The Paleoindian Bison Assemblage from Charlie Lake Cave, British Columbia

A small assemblage of bison bones from the Palaeoindian (10,700 to 9500 BP) components at Charlie Lake Cave, British Columbia is dominated by elements from the middle and lower limbs. The skeletal element frequencies are not typical of a kill site. The lithic assemblage, the lack of evidence for burning, and the ratio of long bone shaft fragments to epiphyses suggest that the assemblage was not produced at a residential site nor at a specialized processing area. We propose that the assemblage resulted from storage of frozen bison limbs in a series of meat caches, probably located in a small cave that would have been difficult for scavengers to enter. Article Summary by Jonathan C. Driver, May 2015 This paper discusses the bison bones from the lower layers, with a focus on the human behaviour that resulted in them being deposited at the site. Excavations at Tse’K’wa uncovered about 100 late ice age bison bones from the lowest layers. These were certainly brought there by people, because they show signs of having been butchered. Some bones have shallow cut marks (made by stone knives) on their surface. Others have been smashed open to obtain the fatty marrow inside them. (While we tend to avoid it these days, fat is essential for a healthy diet for people who rely heavily on meat. Bone marrow is an excellent source of fat). Archaeologists have used evidence from animal bones to interpret the activities that take place at a site. For example, kill sites often contain the parts of an animal (such as the heads and the hooves) that were not taken back to camp; on the other hand, camp sites are often places where we see intensive processing of bones to extract nutrients, so bones are often found broken into many pieces. This paper is based on the M.A. thesis of Claudine Vallieres, who undertook a detailed study of the bison bones from the early cultural layers at the site. The Tse-K’wa bison are a bit of a puzzle. The bones don’t resemble what is usually found at kill sites, so we know that this isn’t a “buffalo jump”. The almost complete absence of skulls, backbone and ribs, as well as the low numbers of shoulder and hip bones, suggest that people were mainly bringing bison legs to the site. In particular, the middle and lower parts of the leg seem best represented. We considered the possibility that other parts of the body had been brought to the site originally, and that all the weakest bones (such as the backbone and ribs) had been destroyed subsequently by scavenging animals (such as wolves or bears) or by natural weathering. While there are some bones that have been chewed by large carnivores, we would expect that at least some harder parts of the “missing” bones would survive – especially the teeth and some of the more dense bones. There is no evidence that bones were subject to destruction by weathering – they are very well preserved and their surfaces show little sign of being exposed to the elements for any length of time. So we concluded that the pattern we were seeing was not the result of weaker bones being destroyed. We also noted that the evidence from the stone tools was somewhat unusual. We had found quite a number of large, heavy quartzite chopping tools in the same layers as the bison. Interestingly, none of these had been made at the site (there were no stone chips left behind from their manufacture) – so they must have been made elsewhere, brought to the site, used, and then discarded. There were a few smaller, sharper stone tools, but again very little evidence that they had been made there. So people seem to have been bringing bison legs to the site, together with fully finished stone tools, butchering the bison, and then leaving bones and stone tools there. But there was no evidence that this was a campsite. There was no trace of fire and no evidence for the other tasks that one would expect at a place where people lived, such as manufacture of tools or preparation of hides. Looking through the archaeological literature revealed that ice caves in the western United States were used for thousands of years for meat storage, and both the animal bones and the stone tools in those caves were similar to those found at Tse’K’wa. We therefore proposed that at least some of the bison bones had been stored at the site (perhaps in the cave) during the late fall or winter, as an emergency food supply.