Before revision:  The analytical power of k-mer differences supports the theses that evolutionary advance  serves the needs of nucleic acids (genomes) rather than proteins (genes), and that such differences have often played a role in early speciation events.
After revision:  The analytical power of k-mer differences supports the theses that evolutionary advance sometimes serves the needs of nucleic acids (genomes) rather than proteins (genes), and that such differences have often played a role in early speciation events.