Nakajima Ko began his career in experimental animation with the creation of works such as Seizoki (1964). At his solo exhibition at the Sogetsu Art Center, a space for avant-garde art in 1960s Tokyo, he produced Seizoki by painting directly on the film between screenings. His perennial interest in integrating new technologies, exploring the potential of film, video, and eventually computer animation, joined his desire to explore human intersections with nature, as seen in his Biological Cycle series (1971-); he created the first work in the series, Biological Life (1971-), by copying manipulated film footage onto video, then further manipulating the work with a video synthesizer.