Connie and I heard Doug Owsley of the Smithsonian Institution give the after-dinner address at the Society for California Archaeology awards banquet last Friday night in Ventura. He spoke on his work on the taphonomy of the Kennewick Man find, something I posted on in February.
It was an interesting and amazingly well-illustrated talk. Not having followed the scientific aspects of the find that closely in the past, it was a useful corrective to misconceptions that had crept into my thinking. The fact that many accounts of Kennewick Man talked of the remains eroding out of the bank of the Columbia River had led me to believe that some of the bones were still in situ in the bank. In reality, the skeleton was out of context as a scatter of bones along the beach. Also, I was not aware of how fragmented the remains were. For example, the cranium was in 11 pieces, so there was a lot of reconstruction to do.
The February press release said that Owsley had established that the burial was intentional, was an "extended" burial (straight out, flat on his back), was parallel to the river, and that the head was pointed upstream. Owsley explained how he came to those conclusions. Those of us who live in arid or semi-arid climates know that calcium carbonate collects in layers in our soils. It's commonly known as caliche. Any hard material such as stone or bone that is buried within one of these caliche layers collects calcium carbonate deposits on its underside. When this phenomenon occurs over long periods of time, grains of sediment actually become cemented to the underside of the buried material.
The Kennewick bones had a consistent pattern of cemented sediment on their undersides. Owsley was able to trace the attitude of each bone's location as it was buried. This was consistent with the pattern of an extended burial. The pattern showed that the cranium was not lying flat, but had been propped up with something under it. This coupled with the fact that the bones showed no sign of perimortem disturbance or animal scavenging led him to conclude the burial was intentional.
Owsley was able to determine the body's position relative to the river by patterns of "corrasion" - wear by water-bourne sediment - on the bone. Bones on the left side of the body showed consistent patterns of corrasion, more than on the right side, indicating that this was the side of the body that eroded out of the bank first. Geological reconstruction of the river channel has shown that when the body was buried the Columbia was 400 yards away.
As I said, this phase of Owsley's work has focused on taphonomy, how the body came to be buried and preserved. There are multiple continuing studies on other aspects of the find, and he talked somewhat off the cuff as to where these are going.
Much has been made of the projectile point imbedded in Kennewick Man's hip bone. CT scans have shown that it was a healed wound and told us more about the point. It is apparently a stemmed serrated dart point. The point entered the body at an angle of 77 degrees, sliced off part of the edge of the hipbone before imbedding itself. This first impact apparently broke off the tip of the point, and that and the bone fragment came loose in the wound. Owsley believes the amount of force necessary to do this and the steep angle of entry indicate it was done by an atlatl dart. A thrusting spear could not have done that amount of damage at that angle.
The base of the point was broken in a fracture showing a twisting application of force. After he was impaled by the dart, Kennewick Man (or one of his companions) yanked and twisted (ouch!) the shaft of the dart until the point broke off and the shaft came free. You can imagine the wound.
Owsley believes that Kennewick Man was somewhere between 35 and 40 years old when he died. He was extremely muscular in the upper body and the humeri were very bowed. Use was very heavy on the right side. A comparison photograph of the heads of the humeri showed an astonishing size difference on that side. He also spent extended periods of time squatting or kneeling, as revealed by the pattern of arthritis in the knees. Owsley admitted he was only speculating, but in his opinion, Kennewick Man, "...looked like a guy who had spent a lot of time in a canoe."
The teeth showed extreme wear, so much so that Owsley believes it is more than can be accounted for by diet. The wear is probably from some task activity such as chewing hides to soften them. Christy Turner and a team of specialists are working on detailed studies of the teeth. More will come later on the teeth.
I speculated in my earlier post as to whether DNA samples had been procured. I found out from another source since then that an attempt had been made several years ago, but that it had failed. Owsley said that the attempt was made using a rib fragment, not the best choice. More attempts will be made in the future using root pulp from the tooth sockets, the preferred site these days.
Finally Owsley reiterated others' opinions that Kennewick does not look like modern Native Americans. He looks more like modern Ainu or Polynesians - but doesn't look closely like them either. Owsley has looked at the other extant Paleoindian skeletons and believes that they are all distinct from modern Native Americans, who don't appear until 7 - 8,000 BP. There also don't appear to be transitional forms, where the populations can be seen gradually changing into modern Native American types. This appears to be a sharp break.
This talk served to tell us how much more we will be learning about Kennewick Man and how much more we need to learn about Paleoindians.
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