Although ant-people have appeared in literature all the way back to classic times (eg, the Myrmidons of the ancient Greeks, and Herodotus mentions giant gold digging ants in his Histories), the most likely source for giant ants in at the time of AD&D's creation was probably the 1954 sci-fi movie Them! (a movie which also had a heavy influence on James Cameron's 1986 movie Aliens).