 During the early 1950s bebop remained at the top of awareness of jazz, while its harmonic devices were adapted to the new "cool" school of jazz led by Miles Davis and others.It continued to attract young musicians such as Jackie McLean, Sonny Rollins, and John Coltrane.As musicians and composers began to work with expanded music theory during the mid-1950s, its adaptation by musicians who worked it into the basic dynamic approach of bebop would lead to the development of post-bop.