Leonard McCoy payment for his appearance. In the "" episode "", McCoy mentions he has a daughter, Joanna. Although Chekov's friend Irina in the original series episode "The Way to Eden" was originally written as McCoy's daughter, it was changed before the episode was shot. In the 2009 "Star Trek" film, which takes place in an "alternate, parallel" reality, McCoy and Kirk become friends at Starfleet Academy, which McCoy joins after a divorce that he says "left [him] nothing but [his] bones." This line, improvised by Urban, explains how McCoy earned the nickname "Bones". McCoy later helps get Kirk posted aboard the
Star Trek: The Original Series show. "Star Trek"s first-season ratings would in earlier years likely have caused NBC to cancel the show. The network had pioneered research into viewers' demographic profiles in the early 1960s, however, and, by 1967, it and other networks increasingly considered such data when making decisions; for example, CBS temporarily cancelled "Gunsmoke" that year because it had too many older and too few younger viewers. Although Roddenberry later claimed that NBC was unaware of "Star Trek"s favorable demographics, awareness of "Star Trek"s "quality" audience is what likely caused the network to retain the show after the first and second seasons. NBC