Collotype print by Eadweard Muybridge, Plate 728, 'Lioness Walking', from 'Animal Locomotion; an Electro-Photographic Investigation of Consecutive Phases of Animals Movements, 1872-1885', published in 1887.

In 1883, the University of Pennsylvania commissioned Muybridge to produce a photographic study of animal and human movement that they hoped might help to analyse diseases and malfunctions of movement. Guided by a committee of scientists, Muybridge nevertheless still approached the project as an artist. Animal Locomotion included over 19,000 photographs in a very expensive 11-volume set, aimed at connoisseurs and libraries. He focused on the narrative and aesthetic qualities of the photographic sequences.