Arch Lake Woman: Physical Anthropology and Geoarchaeology

Discussion and Conclusion

Study of the Arch Lake Site 78 discussion and Conclusion ✦ T he Arch Lake woman is among the oldest Paleoamerican human remains yet found. The remains of this young woman were buried fully extended in a grave that was dug 1.1 m (3 feet 6 inches) deep into a sandy deposit. The cross section of the pit, sketched and photographed in 1967, indicate that the grave walls were nearly vertical. Associated materials included a probable bone tool, a resharpened flake tool, a type of red ocher, and talc beads. Talc is a white to dark green hydrous magnesium silicate. It is a secondary alteration mineral usually found in metamorphic rocks. Because of its soft, smooth texture it was commonly used in native carvings, although this is the oldest example from a dated north American burial context. The Arch Lake skeleton was dated by different radiocarbon laboratories using multiple chemical fractions to determine the remains’ geologic age and paleodietary information. Because the skeleton had been treated with a variety of preservatives that required sequential removal and the collagen preservation was variable among skeletal elements, laboratory results varied as laboratory work proceeded. The best estimate of the skeleton’s age is 10,020 ± 50 RC yr. BP (CAMS-61133), which corresponds to a 1-sigma calibrated age range of 11,260 to 11,640 CAL yr. BP (table 4). The best estimates for the stable isotope values from bone collagen are ∂13 C = –14.1‰ (PDB) and ∂15 n = +13.0‰ (AIR). These data are consistent with an omnivorous diet containing significant amounts of animal protein. Cultural affiliation of the remains is undetermined, neither the talc beads nor the stone tool being culturally diagnostic. Evidence for biological affiliation was garnered through analyses of the cranium, dentition, and post-cranial skeleton, and shows strong differentiation in all aspects from modern native Americans. In addition, the Molecular Anthropology Laboratory of the University of California at Davis processed a small sample of the right femur in an attempt to recover mitochondrial DnA; none was obtained. Archaelogical Comparisons 78 79 Cranial and post-cranial morphology show the Arch Lake woman to be different from other ancient American skeletons in some respects, similar in others, and strongly differentiated from modern native Americans. Cranial vault shape differs from all other early crania in being brachycranic, although Gordon Creek, characterized as mesocranic, approaches this condition. The Arch Lake cranium is similar to other early American crania in having a low face. The low face appears to be the most consistent feature of early Americans and is also found in early people of the eastern Pacific Rim (Jantz and Owsley 2005). The general conclusions to be reached from Arch Lake woman’s postcranial skeleton is that she was tall, evidently taller than any other female skeleton from the period 8000 RC years ago or earlier. Some of these early individuals , such as from Gordon Creek, are quite small (Breternitz et al. 1971). Robusticity varies considerably depending upon anatomical region. The femur midshaft and tibia are not especially robust. The subtrochanteric femur is more robust, and the humerus is very robust. Humerus and femur muscle attachments are not strongly developed, although this is at least partially due to her young age. Wescott’s (2001) results for the femur could be taken to mean that the Arch Lake woman was active in the sense of placing loads on the legs, rather than covering long distances on foot. Humerus robusticity suggests a pattern of activity emphasizing upper body strength. This, in combination with a diet including significant quantities of meat implied by a δ15 n bone collagen value of +13.0‰, may suggest that bison hide working was part of this pattern of activity. The absence of femur platymeria differentiates the Arch Lake skeleton from modern native Americans, especially those of the Southwest, where it is marked. The overall morphological pattern distinguishes Arch Lake from modern native Americans and most early Americans. It therefore supports previous analyses showing that early Americans are distinct from recent Indians , while at the same time increasing the apparent diversity seen among early Americans. The youth and relatively unworn dentition of the Arch Lake woman facilitate analysis of dental features as a means of assessing population relationships . Christy Turner has conducted extensive background work in this regard , noting a classification distinction between two Asian groups: northern Discussion and Conclusions Study of the Arch Lake Site...