New genetic information comes from random mutations in information carrying segments of DNA. A mutation that changes the structure (and, hence, function) of a protein, or the quantity of that protein (which also affects its function) is a mutation that has introduced new information.
Mutations occur frequently, and some things—radiation, mutagenic chemicals—speed up the already fairly rapid rate of mutation. Luckily, living organisms have evolved a number of redundant DNA repair mechanisms, or the rapid rate of DNA mutation would make life almost impossible.
Germ cell mutations are the only ones that matter from the evolutionary standpoint. There are a lot of factors that impact whether a mutation in a germ cell will disappear or spread throughout a population. Every single person has about 150 to 200 new mutations that did not exist in either parent.
New genetic information