Animation has existed since prehistoric times, with one of the earliest examples being an 8-legged boar drawing in the Altamira caves over 10,000 years old. Early animation concepts included Egyptian wall drawings from 2000 BC depicting wrestlers in motion and Leonardo Da Vinci's illustrations of limbs in different positions. Animation was made possible by the persistence of vision, the phenomenon where the human eye retains an image for a fraction of a second after seeing it, first demonstrated in 1828. Early animation devices included the Thaumatrope in 1828 and the zoetrope in 1860, which used successive drawings to create the illusion of motion. The development of film cameras and projectors in the late 19th