Whenever patterns are replicated, there is some probability of error (mutation). Some of those will increase the replication rate, and that error will dominate. This process is evolution.
In relation to DNA based life, it is generally accepted that:
This used to be somewhat controversial - particularly with the religious groups found in Arts faculties of universities because it undermines much of their teachings. It is still resisted with some stubbornness, and Arts academics occasionally leap on some new discovery which they hope will disprove the theory. But overall, it is now becoming increasingly accepted. It is forcing the religious to adapt their teachings to maintain any credibility.
In 1859 Charles Darwin published 'Origin of Species' which laid out the theory. After the discovery of DNA, these theories were refined into modern Selfish Gene Theory.