David Marks is an American songwriter and musician. He is best known as being a member of The Beach Boys from February 1962 to October 1963, and of later versions of the band, including a reunited version that will be recording and touring in 2012. Marks was part of the Beach Boys line-up, at age 13, when they signed with Capitol Records on July 16, 1962. Marks performed on the band’s first four albums, playing rhythm guitar and singing harmony.
Source - http://en.wikipedia.org/wiki/David_Marks_%28musician%29