Johnny Hart (1931-2007) was a cartoonist who wrote and drew B. C. and scripted The Wizard of Id (with Brant Parker). In 1969, the latter strip was adapted for an unaired short pilot.

A running gag in B. C involved the presence of a walking clam, often leading to the phrase "Clam's got legs!" In 2008, as part of the Caroll Spinney Artworks collection, a Caroll Spinney drawing used the gag.