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The Earliest Americans | News and CommentCalifornia - Arlington Springs RemainsOriginally posted 07/31/2001 From the Santa Barbara Museum of
Natural History Dr. John Johnson, Curator of Anthropology Our fieldwork this past May (2001) at the Arlington Springs site was designed to provide a geological answer as to the age of the human bones that were found at the site in 1959-60. Dr. Tom Stafford's (Stafford Laboratories, Boulder Colorado) C-14 dating of small samples of bone collagen suggest that the remains date around 13,000 years before present and perhaps as early as 13,500 BP (these are calibrated dates in "calendar years"). In May 2001, Stafford and other members of our research team exposed the geological strata at the site and collected samples of charcoal and other organic materials to corroborate the dates we had obtained by directly dating the bone collagen. With regard to the DNA testing, here is the story. Last year Dr. David Glenn Smith of U.C. Davis, an expert in extracting mitochondrial DNA from old bone, conducted the tests with two of his advanced graduate students. Restriction analysis of one of the samples initially indicated that the mitochondrial DNA of Arlington Springs Woman belonged to Haplogroup B (one of the five predominant clades of mitochondrial DNA lineages found among Native Americans). Dr. Smith and his team presented this result along with other tests of ancient skeletal remains from North America in a symposium at last year's American Anthropological Association meeting in San Francisco. It must be pointed out, however, that Dr. Smith's lab was unable to replicate their finding of mtDNA in the Arlington bone in subsequent tests using the samples that were left from what we had sent them originally. This less than satisfying result could be due either to the poor state of DNA preservation in bone of this antiquity or contamination by other DNA from an another sample during the lab work (although due care was taken with the samples to avoid such contamination). Dr. Smith continues to accept tentatively the Haplogroup B determination, although successful sequencing of the hypervariable section of the mtDNA would be needed in order for us to have full confidence in this finding. The claim of a match with Arlington Springs Woman was made prematurely by a woman whose mitochondrial DNA lineage belonged to Haplogroup B. She assumed incorrectly that if Arlington Springs Woman also belonged to Haplogroup B, then there was a match. Her assertion was the result of a misunderstanding of the information I had provided to her in a telephone conversation. By the time I had an opportunity to correct her on this, she had already spread the word on the web via an on-line discussion group pertaining to archaeology and Native Americans. Only if we are able to obtain a valid sequence of the hypervariable region of the mitochondrial DNA from Arlington Springs will it be possible to determine if there is a "match" with any contemporary American Indian lineages. It should be noted that the time depth is such that there has been plenty of opportunity for random mutations to occur in the mitochondrial DNA over many millennia that could produce many possible descendant lineages of Arlington Woman's original haplotype. John Johnson
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