Well, you hear it in Led Zeppelin, too. While the members were heavily influenced by the blues artists of the time, songs like "gallows pole" and "Bron-Y-Aur St

Well, you hear it in Led Zeppelin, too. While the members were heavily influenced by the blues artists of the time, songs like "gallows pole" and "Bron-Y-Aur Stomp" and "Hey hey what can I do?" show that influence. They also have a variety of songs heavily influenced by the Rockabilly genre, which also has a folk-roots influence. "Hot Dog", "boogie with stu", and "Candy Store Rock" all count in that regard. Rock and Roll has key influence from both the folk traditions, and the blues ones. And in many ways, baroque and early music which influenced bluegrass.