Radiometric dating or radioactive dating is a technique used to date materials such as rocks or carbon, in which trace radioactive impurities were selectively incorporated when they were formed.The method compares the abundance of a naturally occurring radioactive isotope within the material to the abundance of its decay products, which form at a known constant rate of decay.New discoveries have filled in the gaps, and shown us in unimaginable detail the shape of the great ‘tree of life’.Darwin and his contemporaries could never have imagined the improvements in resolution of stratigraphy that have come since 1859, nor guessed what fossils were to be found in the southern continents, nor predicted the huge increase in the number of amateur and professional paleontologists worldwide.Radiometric dating is also used to date archaeological materials, including ancient artifacts.Different methods of radiometric dating vary in the timescale over which they are accurate and the materials to which they can be applied.and is now the principal source of information about the absolute age of rocks and other geological features, including the age of fossilized life forms or the age of the Earth itself, and can also be used to date a wide range of natural and man-made materials.
For example if you have a fossil trilobite and it was found in the Wheeler Formation.
Our understanding of the shape and pattern of the history of life depends on the accuracy of fossils and dating methods.
Some critics, particularly religious fundamentalists, argue that neither fossils nor dating can be trusted, and that their interpretations are better.
There are two main methods determining a fossils age, relative dating and absolute dating.
Relative dating is used to determine a fossils approximate age by comparing it to similar rocks and fossils of known ages.