PSYC18H3 Chapter 1: Chapter 1
Document Summary
At that time, the accepted theory was that god had given humans special facial muscles that allowed them to express uniquely human sentiments unknown to animals. Humans descended from animals, but we are ourselves animals. He observed emotional expressions in nonhuman specials, as well as in adult and infant humans. Used photographs of naturalistic and posed expressions to make scientific points. Darwin concluded that emotional expressions derive largely from habits that in our evolutionary or individual past had once been useful; based on reflex-like mechanisms. Emotional expressions showed the continuity of adult human behavioural mechanisms with those of lower animals and with those of infancy; they were like vestigial parts of our bodies. Eg. appendix (a small functionless organ in our digestive system) provides evidence that we are descended from pre human ancestors in whom this organ had use. Our emotions link us to our past, both to the past of our species and to our own infancy.