Page 16 - Emotions through the eyes of our closest living relatives- Exploring attentional and behavioral mechanisms
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Chapter 1
effects of species, familiarity, and context (Figure 1b, 1c) on emotion perception are examined. Here, familiarity is defined as the familial and/or social relationship between the expressor of emotions and the observer. Context refers to the situation the observer and/or expressor of emotional expressions find themselves in (e.g., tense or relaxed situations).
A window into our evolutionary past
What are the evolutionary roots of emotions? In search of answers to this cardinal question, one logical step we can take is studying emotions in animals that are evolutionarily close to us: the great apes. Studying the behavior and cognition of extant (i.e., still living) great apes is extremely relevant for reconstructing the social and emotional characteristics of the last common ancestor of the Hominidae, as well as early hominins (ancestral humans) (Duda & Zrzavý, 2013). The Hominidae consist of the African apes: gorillas, chimpanzees, bonobos, humans, and orangutans (the only Asian great ape) (Figure 2). The last common ancestor of the African apes and orangutans likely lived about 14 million years ago (Ma) (Goodman et al., 1998), with the most recent common ancestor of chimpanzees, bonobos, and humans living at least 7 to 8 Ma (Langergraber et al., 2012). It is important to remember that evolution has continued for both the great apes as well as humans. Indeed, each of the hominids
Figure 2. Great ape family tree. Bonobos and chimpanzees are humans’ nearest living relatives, followed by gorillas, and then orangutans. Pan and Homo share a common ancestor roughly 7-8 million years ago (Ma). At one point in time, other human species roamed the earth together with or close in time to Homo sapiens. For instance, Neanderthals co-existed with sapiens until Neanderthals went extinct around 40.000 years ago (Higham et al., 2014).
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