stone tools, geologists, primatologists, geneticists and climatologists, among others. Like previous Walking with... series, Walking with Cavemen employed both computer graphics and animatronics to recreate prehistoric life. When possible, footage of actual live animals was used but other creatures, such as mammoths, had to be recreated through computer graphics. The visual effects were, as for previous series in the franchise, created by the visual effects company Framestore. Walking with Cavemen pioneered a new visual technique, the "deep timelapse", in which scenes of climate, environmental and geological change spanning millions of years were put in a timelapse to only take a few moments. The title Walking with Cavemen was settled upon during production. The title was chosen to appeal to the outdated stereotype of human ancestors being cave-dwellers (the programme does not portray hominins in caves until the last episode) in order to turn viewer's expectations on their head and showcase that the past was not necessarily what they imagined it to be. It was determined to begin the series with Australopithecus afarensis, at the time of production the best-documented early hominid. The behaviour of the Australopithecus portrayed in the series was modelled on chimpanzees and was particularly inspired by the chimpanzee research of Jane Goodall. The BBC referred to Walking with Cavemen as one of its "most ambitious TV science projects". In total, the series cost £4 million to make. It was the first installment in the Walking with... franchise to not involve Tim Haines, the creator of the franchise. Walking with Cavemen was instead created by Richard Dale, who served as executive producer and director, and Peter Georgi, who served as series producer. Both Dale and Georgi had a background in documentary filmmaking and had, among other projects, previously worked together on the 2001 documentary film The Human Body. Casting and hominin costumes Although prehistoric animals had been created mostly through computer graphics in Walking with Dinosaurs and Walking with Beasts, it was difficult to produce hominins through this method that were realistic in appearance, expression and movement. In particular no amount of computer graphics would have been able to convincingly portray emotions and allow audiences to determine how the hominins were feeling from looking in their eyes. Failure to convincingly portray human movement and expressions would have broken the "magic" Walking with Cavemen sought to create. As a result, the production team decided to use actors in makeup