One of the common arguments of creationists is that (a) evolutionary theory is based on the radiocarbon dating of fossils, and (b) that dating is utterly unreliable. Both propositions are false. Just for the record, "radiocarbon dating" is only of several methods of radiometric dating, and not one that is important for work on the evolutionary tree. Radiocarbon, specifically, is very useful for archeologists but utterly useless for paleontologists. It is the use of a radioactive isotope of carbon to tell time, given knowledge of the half-life of that isotope. For anything older than about 50,000 years, there is so little carbon-14 left that it can't be measured accurately. For older finds (those of interest to a paleontologist) one looks for the isotopes of other elements, which have longer half-lives and so different ranges of utility. Somebody once tested a dinosaur fossil using the radiocarbon method, and THAT system declared that fossil to be 50,000 years old. This ...