Definition of Molecular Evolution
Molecular evolution is the changes at the molecular level that occur in the genetic material and these changes are known to be the prime cause of evolution. In this, the evolutionary changes at the level of the DNA sequence are determined. Molecular evolution also includes the study of rates at which the sequence of genetic makeup changes, the relative significance of adaptive and neutral changes, and variations in the genome structure.
The techniques employed in obtaining the nucleotide sequences of DNA have drastically improved in the last few decades. The genomes of a number of species including humans, certain viruses have been sequenced.