Animal Emotions: Exploring Passionate Natures

depression, and dogs happiness and dejection? People disagree about the nature of emotions in nonhuman animal beings (hereafter animals), especially concerning the question of whether any animals other than humans can feel emotions (Ekman 1998). Pythagoreans long ago believed that animals experience the same range of emotions as humans (Coates 1998), and current research provides compelling evidence that at least some animals likely feel a full range of emotions, including fear, joy, happiness, shame, embarrassment, resentment, jealousy, rage, anger, love, pleasure, compassion, respect, relief, disgust, sadness, despair, and grief (Skutch 1996, Poole 1996, 1998, Panksepp 1998, Archer 1999, Cabanac 1999, Bekoff 2000). The expression of emotions in animals raises a number of stimulating and challenging questions to which relatively little systematic empirical research has been devoted, especially among free-ranging animals. Popular accounts (e.g., Masson and McCarthy’s When Elephants Weep, 1995) have raised awareness of animal emotions, especially among nonscientists, and provided scientists with much useful information for further systematic research. Such books have also raised hackles among many scientists for being “too soft”—that is, too anecdotal, misleading, or sloppy (Fraser 1996). However, Burghardt (1997a), despite finding some areas of concern in Masson and McCarthy’s book, wrote: “I predict that in a few years the phenomena described here will be confirmed, qualified, and extended” (p. 23). Fraser (1996) also noted that the book could serve as a useful source for motivating future systematic empirical research. Researchers interested in exploring animal passions ask such questions as: Do animals experience emotions? What, if anything, do they feel? Is there a line that clearly separates those species that experience emotions from those that do not? Much current research follows Charles Darwin’s (1872; see also Ekman 1998) lead, set forth in his book The Expression of the Emotions in Man and Animals. Darwin argued that there is continuity between the emotional lives of humans and those of other animals, and that the differences among many animals are in degree rather than in kind. In The Descent of Man and Selection in Relation to Sex, Darwin claimed that “the lower animals, like man, manifestly feel pleasure and pain, happiness, and misery” (p. 448).