Universals and individuality in facial behavior—past and future of an evolutionary perspective

Abstract

Multiple dimensions of facial expression research are reviewed with emphasis in the study of species' homology in both facial action single components and patterns or gestalten. Research over the last 30 years has revealed human universal patterns and some cross-species gestalten that appear as homologies. Recently, researchers are looking into the importance of individuality markers in facial behavior, which can play an important role in the fitness of individuals living in complex social systems and thus might be traceable in their evolutionary path. Chimpanzees, bonobos, and humans were in the center of most of this research with research results pointing toward homologies within the Homo-Pan clade.

Do great apes use emotional expressions to infer desires?

“…Furthermore, chimpanzees exhibit silent baredteeth displays and play faces that assist in social bonding and the maintenance of social groups. In humans, the same bonding function is served by smiling, which looks similar to those chimpanzee displays ( van Hooff, 1967van Hooff, , 1972Chevalier-Skolnikoff, 1973, 1982Preuschoft & van Hooff, 1995;Burrows, Waller, Parr & Bonar, 2006; see Gaspar, 2006 for a review).…”

Face to face with the social brain

“…If bared-teeth display structure is consistent within and variable between individuals, then this variation might reflect individual differences in expressivity. Future studies of expressivity should focus on the individuality of facial displays, rather than the typical structure [86].…”

Empathy, emotional contagion, and rapid facial reactions to angry and happy facial expressions

“…Converging evidence suggests that emotional communication has an evolutionary basis which includes a biological predisposition in both sender and receiver (Buck, 1984;Buck & Ginsburg, 1997;Darwin, 1872;Dimberg, , 1997Preston & de Waal, 2002). It is interesting to note that closely related species, such as chimpanzees, also share with humans the same facial muscles as well as many similar facial expressions (Gaspar, 2006;Gaspar & Esteves, 2011). The abilities for emotional communication and empathic reactions are developed early (e.g.…”