Dinosaurs and carbon dating walker 2016 quaternary dating methods
Biologists actually have at their disposal several independent ways of looking at the history of life - not only from the order of fossils in the rocks, but also through phylogenetic trees. Relative dating is done by observing fossils, as described above, and recording which fossil is younger, which is older.
The discovery of means for absolute dating in the early 1900s was a huge advance.
Today, innovative techniques provide further confirmation and understanding of the history of life.
Older dates may change by a few million years up and down, but younger dates are stable.
For example, it has been known since the 1960s that the famous Cretaceous-Tertiary boundary, the line marking the end of the dinosaurs, was 65 million years old.
Repeated recalibrations and retests, using ever more sophisticated techniques and equipment, cannot shift that date. With modern, extremely precise, methods, error bars are often only 1% or so.
The fossil record is fundamental to an understanding of evolution.