The molecular clock has limited usefulness for estimating divergence times among species in part due to the saturation of DNA se
quences. This occurs because A. DNA sequences are unable to revert back to previous allelic states.
B. the variation in the substitution rate between closely related lineages prevents accurate estimation of divergence time.
C. variation in population sizes among lineages changes the effect of genetic drift.
D. in highly diverged lineages, substitutions will occur at sites that have been substituted previously
<em>In highly diverged lineages, the substitutions process will occur at sites that have been substituted previously</em>.
<u>Explanation:</u>
Molecular clock uses the mutation rate to reduce the time in prehistory when the life forms are diverged. <em>The molecular clock uses the sequence of amino acids and nucleotide sequence for the DNA.</em>
This clock does not measure any time but the number of mutations, and other changes over certain time. <em>Sometimes its useful property might be limited due to the highly diverged lineages.</em>
Allopatric speciation happens when a geographical or physical barrier is introduced in a population. After this, the reproductive isolation, genetic recombination and also random mutations can promote the speciation process, where at the end, there will be two separate species.
I want to say that it would be the 'atomic radius' that would increase. Because as this would happen, the atoms would then get smaller and smaller, mainly because the radius would just get smaller and also the atoms would also.