Another advantage is that it actually shows how the pieces of the theory were assembled. Because they all made sense individually, they made better sense as a unified theory. Different proportions of radioactive isotopes of the same elements in rocks are seen to provide a basis for calibrating their age, resulting in the geologic time scale. Radioactivity, not combustion, is identified as the source of the Sun's energy, indicating that it is much older than the 100,000 years previously calculated by physicists. These models are consistent with observations of population changes in the wild and in laboratories.
Geophysicists object that there is no known mechanism to move solid rock through solid rock.
The genetic material, DNA and RNA, is described as a double helix of parallel codon triplets of amino acids. Observations and calibrations of relative changes in this redundant genetic material allow the reconstruction of relationships of organisms on the basis of degree of divergence of their neutral genetic material. We form and test these hypotheses just as we test hypotheses about biological evolution. Hence these methods are independent, and do not rely on preconceptions of evolutionary history read from fossils. Radiometric dating doesn't depend on the geologic record at all, but on the principles of physics and chemistry.