'Cat terrified at a dog', 1872.
© Science Museum / Science & Society Picture Library
Drawing from life by Mr Wood. Plate taken from 'Expresion of the Emotions in Man and Animals', published in 1872 by Charles Darwin (1809-1882). Darwin, the great British naturalist and originator of evolutionary theory, made this study of animals to disprove the contemporary belief that only humans were capable of expresing true emotion. He cataloged many different animals' facial expresions and their use of body language to expres feeling. He recorded that: 'Cats, when terrified, stand at full height and arch their backs in a well-known and ridiculous fashion. They spit, his or growl. The hair over the whole body, and especially on the tail, becomes erect.'