Chapter 1: Paleo-Indians and Mammoths

Californian Paleo-Indian Skeletons

When have the first Indians lived in California? How reliable are the dates, which they have published about them? What of some of the world’s leading experts now found out about this?

J. L. Bada, Amino Acid Dating Laboratory, Scripps Institution of Oceanography, University of California at San Diego; R. Gillespie and R.E.M. Hedges, Oxford Radiocarbon Accelerator Unit, Oxford University, have published in the scientific journal Nature their findings:

“A decade ago, asparatic acid racemization ages were determined for some skeletal remains found in California, near La Jolla, Del Mar and Sunnyvale, suggesting that people were present in North America during the Upper Pleistocene. These ages were obtained from the aspartic acid racemization rate, which was calibrated using a radiocarbon date of 17,150+/-1470 yr BP determined from a skeleton found in Laguna Beach, California. ...

“Here we have used accelerator mass spectrometry (AMS) to determine the radiocarbon ages of the amino acid extracts used in the original racemization studies. Our studies indicate that some of the controversial Californian skeletons, which have been assigned to the Upper Pleistocene, are in fact Holocene.

“Bone collagen undergoes hydrolysis via a series of reactions, beginning with cleavage at labile peptide bonds such as those containing aspartyl and seryl residues. The peptides liberated by this hydrolysis are further degraded via peptide bond hydrolysis and an internal aminolysis reaction, which takes place at the N-terminal end of the peptides. If, during the process of collagen hydrolysis, the aspartyl residues end up primarily at the N-terminal positions of the peptide hydrolysis products, this could give rise to rapid racemization rates as amino acids at the N-terminal position in peptides have been found to have racemization rates greatly exceeding those of other positions.

“The skeletons having low amino acid content were found to be depleted in 4-hydroxyproline and enriched in the acidic amino acids, although the general amino acid composition of these samples still somewhat resembled that of collagen. This indicates that the collagenous matter is these bones has undergone severe diagenesis, which may have altered the D/L Asp ratio. The factors which have contributed to the extensive collagen hydrolysis in some of the skeletons are not known, but probably include leaching by ground waters and heating effects resulting from either shallow burial depths or cultural burial practices. Also many of these Californian skeletons come from coastal shell middens in which the presence of carbonates in the burial soils may have greatly accelerated the rate of collagen hydrolysis.” Bada, J. L. et al. (1984:442-444). - Diagenesis: Recombination or rearrangement of constituents of a chemical or mineral.

Northern Yukon Dates

How reliable are the radiocarbon dates on fossils from the frozen ground in the northern Yukon Territory? – D. E. Nelson and co-workers report about their findings in the journal Science, under the heading, “New Dates on Northern Yukon Artifacts Not Upper Pleistocene”:

“New radiocarbon dates on four artifacts were thought to provide evidence for human occupation of the Yukon Territory during the Upper Pleistocene indicate that all four are of late Holocene age. The original radiocarbon age obtained for one artifact (the so-called ‘Old Crow flesher’) was in error by almost 26,000 years. ... the dates obtained for the flesher, the billet, and the two antler wedges show that these are Holocene, not Pleistocene artifacts. In particular, the age 1,359+/-150 BP) obtained for the flesher is almost 26,000 years younger than that originally measured.” - Nelson, D. E. et al. (1986:749, 750).