Skeletons from California, racemization

Table III. Racemization of Aspartic Acid in Holocene Radiocarbon-Dated Aboriginal Skeletons from California...

Table IV. Racemization Ages of Holocene Aboriginal Skeletons from Southern California Coastal Sites ...

AMS/HEMS system at the University of Arizona, direct counting of three organic fractions of bone from a human skeleton from the Sunnyvale Site in California, previously dated by the amino acid racemization technique at about 70,000 years, resulted in a revised date of between 3500 and 5000 years b.p. 

IS). The Holocene samples which we investigated came from a variety of localities which diflEered greatly in their general environmental characteristics. If variations in environmental parameters could produce anomalously high racemization, this should have been detected in at least some of the samples which we analyzed. Since the extent of racemization in the Holocene samples from throughout California is consistently much less than in the Del Mar Man skeleton, etc., this indicates that the most reasonable explanation for the highly racemized amino acids in these latter skeletons is that they are considerably older than the Holocene skeletons. 

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