No. 99: May-Jun 1995
Pursuant to the possible effect of the earth's recent envelopment by a molecular cloud on the accuracy of carbon dating (SF#98), we now look at the potential distortion caused by the ingestion of primordial carbon (carbon-13) by plants and animals. Primordial carbon may come from limestone or natural gas welling up from the earth's interior. Modern life forms that metabolize primordial rather than atmospheric carbon dioxide, with its cosmic-ray produced carbon-14, will appear extremely old when carbon-dated.
For example, M. Grachev et al carbon-dated flatworms and a sponge collected from a bacterial mat near a thermal vent 420-meters deep in Lake Baikal. The apparent ages of these living organisms ranged from 6860 to 10,200 years.
(Grachev, M., et al; "Extant Fauna of Ancient Carbon," Nature, 374:123, 1995)
Even animals eating these apparently ancient life forms may take up their carbon-13 and, in effect, be drained of carbon-14. They would appear to age rapidly. Such false aging has actually been induced in the laboratory with mice fed on brewer's yeast grown in natural gas. These mice, living in cages at Lawrence Livermore National Laboratory, California, were carbon-dated as being 13,000 years old, and were expected to attain a ripe old age of 35,000 in a few months. (All this was part of a cancer-research project.)
Of course, most carbon-dating in archeology is not endangered by the primordial-carbon problem. But, as K. Turteltaub, "father" of the Lazarus mice, commented:
"We've joked about sprinkling them [the mice] around archeological sites just to confuse everyone."
(Weisman, Jonathan; "Of Lazarus Mice and Carbon-14," Tri-Valley Herald, July 12, 1993. Cr. R. Berg)