Wednesday, Oct. 28, 1998

Chatters tells about bones' condition

Report on the Condition of the Kennewick Man Skeleton on October 28, 1998 by James C. Chatters, Ph.D.

Introduction

I inspected the Kennewick Man remains on October 28, 1998, as authorized by order of the court in Bonnichsen et al. v. U.S. The principal focus of my inspection was to determine if any changes had taken place in the collection since I had last seen it on August 30, 1996. My concerns were as follows:

-- Condition, particularly fractures, cracking, warping, exfoliation (flaking), and algae development.

-- The presence of extra bones, particularly the purported extra pubis and the collections made by tribal staff.

-- The absence of bones from the original collection.

Condition

Cracking and Breakage

1. This crack begins in the anterior aspect of the greater wing of the sphenoid, near the body, and ascends this process to approximately 10 mm below pterion. It appears slightly wider than before, but is otherwise unchanged.

2. The crack (1) continues to just above pterion and is separated from other segments by two anterior branches. The portion of the sphenoid and frontal bounded by these cracks was displaced laterally by 0.3 mm in August 1996. It is now displaced 1.7 mm laterally, an increase of 467 percent.

3. This segment in the parietal has widened from a hairline to 0.2 to 0.3 mm.

4. A new 42 mm-long crack has formed posteriorly along the squamous suture from approximately pterion.

5. This segment, extends posteriorly in the parietal from near the coronal suture to posterior to the temporal line. Although it has lengthened only 6 mm (72 to 78 mm), it has widened at its anterior end from 0.3 mm to 0.7 mm.

6. This superior-most segment of the crack system has not lengthened, but has widened from 0.3 to 0.8 mm.

An additional pair of cracks has developed in the roof of the left orbit. The medial of these is 22 mm long and is displaced approximately 1 mm; the lateral is a 18 mm-long hairline.

In 1996, upon first noticing the cracks, I took steps to retard the drying of the bone and preserved it with a water based polymer. In addition, to counteract stresses that led to warping, I had bound the skull with two broad rubber bands. These bands have been removed from the skull and their absence may account for some of the severe cracking and displacement of the bone.

Maxilla and Maxillary Teeth. Maxillae are in good condition, with little change since August 1996. A very fine crack has developed in the inferior aspect of the left zygomatic process and cracks have widened slightly in the left first and second molars, and right first incisor and canine.

Zygomatics. The left zygomatic has developed a horizontal crack in the posterior surface of its frontal process, which alters the shape of the bone and may make it difficult to fit this element to the frontal for taking craniofacial measurements. The right zygomatic is unchanged.

Pectoral Girdle. All major bones show new, hairline cracks, usually oriented along collagen fibers. This includes the left clavicle, both scapulae, both humeri, and both radii. In most cases, this minor cracking does not affect the scientific potential of the bones. However, in the left ulna, broad cracks have formed on either side of the break between the two proximal-most fragments. Two major cracks in each segment have widened to 1 to 2 mm and longitudinal sections of the bone appear ready to break away. During re-packaging, the Government's conservators gave this piece special attention to reduce the risk of breakage.

Tibia and Fibula. There is significantly more cracking in the tibiae. This is especially evident in the right tibia, which has multiple radiating cracks across its distal articular surfaces and the anterior aspect of the diaphysis. Cracks in the diaphysis are longitudinal and in the midshaft segment there is a risk of exfoliation. The proximal end of this bone has broken into two parts. The fibulae are similar, with wide longitudinal cracks in the articular surfaces.

Algae

Although the conservator's report dated November 1997 expressed concern about the presence of algae on some of the bones, this algae is dead and has been since August 1996. It results from the bones having lain on the moist beach or just below the water surface for some months prior to recovery. The same is true of the differential coloration of the bones: darker fragments were covered by reservoir mud, lighter ones had lain exposed to the bleaching effects of sunlight.

Extra Bones

Collection A

The elements identifiable as human include Kennewick Man's fifth cervical vertebra, the neural arch of his first thoracic vertebra, which fitted the vertebral body I recovered, four rib fragments, three of which were matched to breaks in the rib cage of Kennewick Man, a fragment of right iliac crest matching a gap in the right ilium, a segment of the shaft of the right second metatarsal, matching Kennewick Man in size and shape and filling a gap in the right foot bones, the fourth and fifth proximal phalanges of the right foot, again, filling a gap in the collection and matching the skeleton in size and shape, and a fifth proximal phalanx of the left hand, again, matching and fitting into the Kennewick Man skeleton. The proposed third pubis proved to be a fragment of the right ischium of Kennewick Man. The remainder are unattributable fragments.

Collection B

The single bone under this designation is the left first metacarpal, which matches Kennewick Man in size and shape and completes the metacarpals of the left hand.

Missing Bones

Absent from the collections were the rib segment I found in December 1997 and the small bone fragments the Corps reported collecting in 1998 just before burying the site. It would have been advisable to have had these bones on hand to be included in the full inventory of the remains. I presume they were among the bones taken from the collection in April 1998.

Summary

In general, the Kennewick Man skeleton is in good condition, but some severe cracks have developed in the skull, pelvic bones, tibiae, and left humerus. The displacement and width of cracks in the right frontal and left sphenoid, frontal, and parietal are of serious concern. Algae is not a matter of concern. There is no indication any algae has developed since the bones were brought into the laboratory and placed at PNNL. All human bones collected by tribal parties and identifiable to element are part of the Kennewick Man skeleton. The only missing bones are the majority of both femora, a deficiency that has significant consequences for scientific study of the skeleton. Bones collected by the COE in April 1998 were not present with the collection and thus could not be inventoried.

James C. Chatters, Nov. 23, 1998