why isWhy is DNA useful in tracing evolutionary changes?

Question

alphadxg · Answer

Well, lets be reasonable, why do you think so?

anonymous · Answer

@tayana @alphadxg This is actually more complicated. Have you heard of homologous traits? Basically two traits are homologous if they arise from the same thing. So, butterfly wings and bat wings are not homologous. Our arms and bats wings are homologous because the are the same bones, evolutionary speaking, altered to be specialized for different purposes.

DNA is helpful because the genes are homologous. So, the ribosomal small subunit rRNA is homologous in bacteria, archaea, and Eukaryotes, for example.