The Expression of the Emotions in Man and Animals typically accompanies blushing. A German translation of "The Expression" appeared in 1872; Dutch and French versions followed in 1873 and 1874. A second edition of the book, with only minor alterations, was published in 1890. Before Darwin, human emotional life had posed problems to the western philosophical categories of "mind" and "body". Darwin's interest can be traced to his time as a medical student and the 1824 reprint of Sir Charles Bell's "Anatomy and Philosophy of Expression" which argued for a spiritual dimension to the subject. In contrast, Darwin's biological approach links mental states to the coordination of movement, and
Body language postural expressions of emotions such as anger/aggression, happiness, and fear. These similarities support the evolution argument that social animals (including humans) have a natural ability to relay emotional signals with one another, a notion shared by several academics (Chevalier-Skolnikoff, 1974; Linnankoski, Laakso, Aulanko, & Leinonen, 1994). Where Darwin notes similarity in expression among animals and humans, the Cultural Equivalence Model notes similarity in expression across cultures in humans, even though they may be completely different. One of the strongest pieces of evidence that supports this model was a study conducted by Ekman and Friesen (1971), where members of a preliterate