Technically speaking, the idiots above are somewhat correct. The Beatles were a middle man in influencing modern rock, albiet a very important middle man. Early blues musicians from America were the true influential backing for most of the 60's and 70's. BUT, the Beatles were the first band to truly take the bluesy sound and transform it into what we see as modern rock. you can even track this progression through their discography, each album growing more like rock, and with a more bluesy background. Now the persons above do not seem to realize just how pivotal a role this was. No one had ever before done anything like this. This paved the way for such groups as the Rolling Stones, Led Zeppelin, and the like. The Beatles music in general may be slightly overated (although i do not belive so) BUT the musical importance of it is in NO way overated, it was such an enormously pivotal role in the transition from early rock to what is now called modern rock it is hard to imagine what would be considered modern rock if fate had not brought together some of the most musically talented individuals the 60's, or the 20th century for that matter, saw.
Backwoods guitar to Blues to The Beatles to Rock, yes, evolution does in fact exist.