However, the amount of C-14 has not been rising steadily as Cook maintains; instead, it has fluctuated up and down over the past ten thousand years. From radiocarbon dates taken from bristlecone pines.
There are two ways of dating wood from bristlecone pines: one can count rings or one can radiocarbon-date the wood.
ICR creationists claim that this discredits C-14 dating. Answer: It does discredit the C-14 dating of freshwater mussels, but that's about all.
Kieth and Anderson show considerable evidence that the mussels acquired much of their carbon from the limestone of the waters they lived in and from some very old humus as well.
So, if we measure the rate of beta decay in an organic sample, we can calculate how old the sample is. Question: Kieth and Anderson radiocarbon-dated the shell of a living freshwater mussel and obtained an age of over two thousand years.It is easy to correlate the inner rings of a younger living tree with the outer rings of an older dead tree.The correlation is possible because, in the Southwest region of the United States, the widths of tree rings vary from year to year with the rainfall, and trees all over the Southwest have the same pattern of variations.When experts compare the tree-ring dates with the C-14 dates, they find that radiocarbon ages before 1000 BC are really too young—not too old as Cook maintains.For example, pieces of wood that date at about 6200 BC by tree-ring counts date at only 5400 BC by regular C-14 dating and 3900 BC by Cook's creationist revision of C-14 dating (as we see in the article, "Dating, Relative and Absolute," in the , not too old.