a popularly accepted “universal constant” even though the foundations on which it was based have been virtually removed.
Some evidence is also presented to show that radiometric results that are in agreement with the accepted geological time scale are selectively published in preference to those results that are not in agreement.
The age of the fossil must be determined so it can be compared to other fossil species from the same time period.
Understanding the ages of related fossil species helps scientists piece together the evolutionary history of a group of organisms.
In 1972 this assumption was shown to be highly questionable.
However, none of the criticisms of young earth creationists have any scientific merit.
Some very straightforward principles are used to determine the age of fossils.
Students should be able to understand the principles and have that as a background so that age determinations by paleontologists and geologists don't seem like black magic. Geologists in the late 18th and early 19th century studied rock layers and the fossils in them to determine relative age.
The basic theory of radiometric dating is briefly reviewed.
Since 1955 the estimate for the age of the Earth has been based on the assumption that certain meteorite lead isotope ratios are equivalent to the primordial lead isotope ratios on Earth.