Thursday, July 14, 2005

Lessons From Kennewick: Fitting it all Together

In the first post in this series I mentioned that the Kennewick skeleton had become available for scientific study. In the second post I discussed different techniques anthropologists use to study skeletal material. In the third I showed how these techniques are used in practice and tried to show how one skeleton can improve our understanding of history and of our scientific techniques. In this post I will discuss what is currently known about Kennewick and show how it impacts some of the issues discussed previously. Before continuing I would like to point you to this post for some of the archaeological background. In that post I point out some of the antecedents of North American archaeological assemblages and discuss some of the theories about how the Americas came to be populated. The one thing I left out of that post was a discussion of the people themselves.
It had long been thought that Native Americans were related to peoples somewhere in Asia (defined broadly). For example, one of the goals of the Jesup North Pacific Expedition, led by Franz Boas, in the 1890's was to trace the cultural, linguistic, archaeological and biological relationships between Asian cultures and Native Americans. Based on both skeletal and soft tissue traits it was assumed that Native Americans were related to mongoloid peoples in the old world. More specifically, it was felt that Native Americans, especially Eskimos, were related to peoples inhabiting Siberia. As anthropological methods became more sophisticated ideas changed somewhat - but not much.
E.A. Hooten, one of the more important figures in American physical anthropology, noted that the most mongoloid Native Americans were the Eskimos (coincidentally the most recent to arrive in the Americas) and the as one moved throught North America into South America populations became less mongoloid. This lead Hooten to propose that there were 2-3 separate migration events with the earliest being from non-mongoloid peoples related to populations in India, Australia and the Ainu.
J. B. Birdsell (writer of the popular - for it's time - Human Evolution: An Introduction to the New Physical Anthropology) felt that there may have been some non-mongoloid peoples (mainly the ancestors of the Ainu)involved in the peopling of the America's but felt that the America's were largely settled by mongoloid peoples.
W. Howells (author of the popular Mankind in the Making)felt that Native Americans were descended from a generalized mongoloid stock from which later, more specialized mongoloids (such as the Chinese) developed. Howells felt that populations bearing the closest resemblance to Native Americans could be found in Indonesia, Central Asian and Tibet. Unlike Hooten and Birdsell, Howells felt that mongoloids only were responsible for the peopling of the Americas. This is pretty much where things stand today. The point to take away from this is that there are two competing ideas. One allows for caucasoids in the ancestry of Native Americans. The other doesn't
The Kennewick skeletal material was found in July of 1996 Lake Wallula. It had been in a terrace, part of which claved off taking part of the skeleton with it. The remaining part of the skeleton was bleached by the sun for 1-2 months befor it to eroded out of the terrace. Elements of the skeleton were scattered, by water action, over 300 sqaure feet.


Here you can see what appears to be a tibia in situ.

Here is a view of a large part of the skeleton,



and here is a good view of the skull.

.

At first there was some uncertainty over whether the find represented, say, a homicide or was prehistoric. Preliminary analysis indicated the find was, indeed, an archaeological dicovery, which brought it under the purview of the Native American Graves Protection and Repatriation Act (NAGPRA) and under the Archaeological Resources Protection Act (ARPA). Of the two NAGPRA is the more onerus. Under NAGPRA a two step process is followed. First, One has to determine whether the remains should be considered "Native American" under NAGPRA's definition. If they are Native American the second step is to determine whether or not the remains are culturally affiliated with any modern day tribe or tribes (if so they are repatriated). Analysis of remains can be a little difficult because in most cases permanent alteration of the remains (by, say, reconstructing the skull) are not allowed. Be that as it may, in order to be in compliance with NAGPRA a number of analysis were performed upon the skeleton. First, an inventory was made of all the skeltal material. Having done that, the skelton was examined using some of the criteria mentioned in the second post. Using these methods it was determined that the skeleton was of a male between 45-50 years of age. The femurs and tibia were broken so the humerus was used to determine stature. It is estimated that the stature of the individual was between 5'8" and 5'10". The skeleton was also examined for pathology and post mortem damage. The skeleton showed some signs of osteoarthritis. There was localized trauma on the radius, and scapula. The right ilium had what has tentitively been identified as a cascade style projectile point embedded in the right ilium.


A Cascade point (only about three inches long).

Interestingly enough, this injury did not kill the individual, quite a bit of healing took place after the injury. As a matter of fact only the base and tip of the point could be clearly seen. Several of the ribs were broke, although there is some evidence that this represents post depositional damage. There were also some rodent tooth marks on the skeleton. In addition to the bleaching of some of the bones, mentioned above, the skeleton was covered with calcite deposits. Some of the bones also had alghae adhering to them. Some of the bones also had a reddish stain which may have been red ochre - but further analysis indicated the stains were caused by decaying organic matter (roots mainly).

To answer the question of biological affiliation (i.e. was Kennewick related to modern tribes) non-metric and metric techniques were used.

In terms of non-metric traits the Kennewick material contained a variety of features found in Caucasoids and Mongoloids. Caucasoid traits found in Kennewick include a large nasal spine, undulating horizontal ramus (part of the jaw) border, slanting ascending ramus profile, no wormian bones, no os japonicum (this is where a second suture divides the zygomatic bone into two pieces) and cranial sutures of medium complexity. Mongoloid traits include a large malar tubercle (a raised area on the zygomatics) blurred nasal sill, zygomatic posterior tubercle, slight nasal depression, moderate prognathism, elliptical dental arcade, straight palantine suture (the palantines are two bones that articulate with the palate in the top rear of the mouth)and possibly an angled zygomaticomaxillary suture (in caucasoids this suture is "s" shaped) and a forward facing frontal process of the maxilla (this is the area where the maxilla articulates with the frontal and nasal bones - in caucasoids the frontal process slopes steeply away from the nasals). This is where it gets interesting. Some additional traits include an nasal form intermediate between towered and tented , a medium nasal opening, vertical zygomatic bones, and a slightly rhomboidal orbital shape. These traits occur in Polynesian populations (I will get back to this later).

In terms of metric traits an extensive series of statistical analyses were carried out. In order to do this the skull had to be reconstructed, which led to several problems. Since the conservators of the skeleton would not allow permanent alterations the normal glues and what not used in restoring skulls could not be used. In order to take some of the measurements the bones literally had to be held in place by one person while the other measured them. This involved a lot of fitting and refitting of the bones (both cranial and post cranial). A CT scan was also made of the skull, which allowed a polymer cast to be made. Unfortunately, a comparison of the measuremnts of the cast with the skull revealed statistically significant differences in the measurements. Fifty two measurements of the skull were then taken and the measurments were compared to a wide variety of populations around the world. The results were interesting. In most of the tests ran Kennewick was most closely related to populations in southern Japan (i.e. the Ainu) and Polynesia (the Moriori and Easter Islanders) followed by archaic Native American populations such as Indian Knoll and, in some analysis, the Chukchi of Siberia.
The Kennewick skeleton has gotten a lot of press becuase of it's caucasoid affinities and we are now in the position to see how this came about. It should be pointed out that in this context "caucasoid" does not mean European. Rather caucasoids refers to a large highly variable population that includes Polynesians, Australians and the Ainu as well as Europeans. The way I would explain it is that Kennewick arose from the same general population that gave rise to Polynesians, Australians and the Ainu. If you refer back to my discussion of "race" in part three of this series you can see how some of those ideas play out here. In particular, the Brace et al article seems relevant. Some of the traits cluster Kennewick with, say Polynesia (this would be the common descent aspect of the Brace et al article) others are referable to the effects of different selection regimes as each population went their separate ways (my own opinion - for what it's worth - is that Kennewick seems to lend some confirmation to Hooten's theory mentioned above).
Samples were taken from the 3rd left metacarpal for DNA analysis using PCR amplification. Midway through the study analysis was terminated under orders from the Army Corps of Engineers (the skeleton was found on COE property). In the spring of 2000 permission was granted by the Department of the Interior to proceed with the analysis. Unfortunately, investigators were unable to extract DNA suitable for PCR amplification. A sample of the 3rd left metacarpal was also submitted for radiocarbon dating. The results indicvated an age range 5750 - 9510 BP. Investigators felt that there was some intrusive young carbon in the sample yielding the younger dates. But things are a little more complicated than that. Apparently, there is a discrepancy in carbon content between bone samples taken in 1996 and 1999 - which investigators found surprising.
It could be argued that the proper thing to do with Kennewick would be to make some casts (which is not without difficulty given some of the conditions posed on previous investigators) and repatriate the remains. As pointed out in this post there are several outstanding issues that need to be resolved (A better DNA analysis being one). Certainly, research on casts has some legitimacy within anthropology. However, there are precious few skeletons dating to the time of Kennewick and before we turn it over, for what amounts to it's destruction, we had better make sure we get the science right. But then, what of other skeletal material that is just as important. The Over Collection (mentioned in the previous post) has, largely been repatriated. It would not have been possible to make casts of each and every skeleton in the collection. It is, therefore, crucial that scientists be allowed to study this material in a manner consistant with the best scientific practices - which has not been done with Kennewick (which is not to say the previous investigators were less than professional - rather some very severe restrictions had been placed on their ability to perform the necessary studies).

Here are some interesting links to Kennewick:

NPS AEP: Kennewick Man Contains many of the studies used in this post.

Tri-City Herald's Kennewick Man Virtual Interpretive Center

Kennewick Man Home Page From the Burke Museum - where the Kennewick skeletal material is located.