Facial expression the social component of those like shame, pride, jealousy, envy, deference, etc.) and are recognized by people regardless of culture, language, or time. The belief in the evolutionary basis of these kinds of facial expressions can be traced back to Darwin's "The Expression of the Emotions in Man and Animals." Reviews of the universality hypothesis have been both supportive and critical. Work in 2013 by Nelson and Russell and Jack et al. has been especially critical. Ekman's work on facial expressions had its starting point in the work of psychologist Silvan Tomkins. Ekman showed that facial expressions of emotion are
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