There is fairly wide agreement among scientists that some subcategory of moods and emotions have an evolutionary basis: they are variants on moods and emotions that helped our distant ancestors pass on their genetic material through evolutionary mechanisms. The disagreement concerns which moods and emotions belong to this class and whether any significant aspects of moods and emotions are predominantly a result of historically significant movements, cultural customs or social hierarchies without an evolutionary basis.
Basic and Complex Emotions
Following the work of psychologist Paul Ekman (1992), it is common to divide emotions (and mood) into basic (or simple) and complex (non-basic). The basic emotions are joy, surprise, anger, sadness, fear and disgust. Jealousy, love, guilt, grief, and pride are examples of complex emotions.
The basic emotions can combine (synchronically or diachronically) with each other as well as additional psychological or bodily states to form complex emotions that are far from always associated with a universally recognizable facial expression. For example, contempt is a mixture of anger and disgust, and a standard form of grief is a mixture of surprise, sadness, anger and other elements, such as denial, bargaining and acceptance.
Basic emotions are so-called because they are associated with distinct and universally recognizable facial expressions (Ekman & Friesen, 1971). When people experience surprise, for example, their brows arch, their eyes are open wide to expose more white and their jaw drops slightly. When people experience disgust, their upper lip is raised, their nose bridge is wrinkled and their cheeks are raised.
Emotions and moods can be hard to distinguish. However, a commonly adopted distinction is this (Brogaard, 2015). Emotions are about, or directed at, some specific thing or event in the external world, For example, the emotion of anger may be directed at Jack and not Jill. Moods, on the other hand, are not directed at anything specific. They may well have a cause but they are felt as being free-floating. For instance, depression may be caused by a traumatic childhood but it may be felt as mental (and or bodily) symptoms that just occur for no apparent reason, such as the feeling that nothing is fun anymore. and morning grumpiness, afternoon fatigue and restlessness are examples of complex moods.
Ekman did not directly address moods but, as we just characterized them, it seems that many of Ekman’s basic emotions have mood equivalents. Joy, sadness and fear, for instance, can certainly occur in a free-floating form, i.e., without being directed at any specific thing or event in the external world. Some anxiety disorders involve free-floating fear, for instance, fear manifested as an inner mental irritation with no apparent cause. We can thus expect that the moods, like the emotions, can be basic (and thus associated with universally recognized facial expressions) or complex (involving many components some of which are basic moods).
The Evolutionary Basis of Emotions
As noted, the standard criterion for classifying some emotions as basic is based on the finding that they are associated with universally recognizable facial expressions. This is a strong indicator of them having been evolutionarily advantageous (or adaptive). In spite of the fact that complex emotions and moods need not be associated with a universally recognized facial expression, most scientists hold that many of them have an evolutionary basis too.
As an example, consider jealousy. A popular evolutionary explanation of why we experience this emotion in romantic love is that it helped our ancestors survive in civilizations in which women depended on men for most of the nutrition required for them and their offspring’s sustenance (Brogaard, 2015). In these civilizations, women would have benefitted evolutionarily by the emotion of jealousy because the intensity of this emotion may have motivated them to prevent their man from straying. If the man did run off with another woman, she would lose her breadwinner, and the survival of her genetic material would be endangered. The men, too, would have had benefited evolutionarily from the emotion of jealousy because the intensity of this emotion likely would have motivated him to prevent the woman from mating with another man. If his woman mated with another man without his knowledge, he would have no way of knowing that the offspring was not his own. So, he would have wasted resources on bringing up another man’s children, which would not have helped him pass on his genetic material.
Recent studies have shown that jealousy may still play roughly a similar role in modern civilization. In cultures and subcultures where women depend for their livelihood on men’s economic status, men and women alike are more likely to be monogamous, regardless of religious or political attitudes. A likely reason for a stronger adherence to monogamy in these groups is that it benefits the survival of each party’s genetic material. The woman and the offspring depend for their survival on the man staying in the home, so they can continue to receive needed resources, and the man depend for the survival of his genetic material that the woman doesn’t stray, so his resources end up helping the survival of other men’s genes. Jealousy may motivate individuals in these situations to take action to protect against infidelity.
Many complex moods, too, may have had an evolutionary basis. As an example, consider depression--which today is partly defined by the length and intensity of the depressive symptoms. One explanation of its prevalence today is that our ancestors experienced a quick increase in, say, anhedonia or melancholy in critical circumstances, such as when resources were scarce or complicated problem-solving was needed in order to obtain them.
The variation on today’s depressive symptoms we can envisage our ancestors having had under difficult survival conditions may have led them to find fewer non-essential activities pleasurable, being less motivated to start new projects and less likely to engage in rash decision-making. This would allow them to focus more intensely on the problem at hand and use careful analytic thinking to solve it. Those with this variation on today’s instances of depression would have had an evolutionary advantage compared to the more easy-going joyful and impulsive types who would rush the decision-making process and fail to solve the problem of how to survive during their hardship.
Our ancestors thus may not have experienced exactly the same emotions and moods as we experience, identify and name today. In some cases, they likely have experienced briefer, more moderate or otherwise deviating forms of today’s emotions and moods. On this view, today’s emotions and moods are the results of influences from the very different environment we now live in. Take fear as an example. If an ancestor who was out hunting for food encountered a dangerous grizzly bear, a burst of fear would likely have helped her survive. A fear response to the grizzly bear would be associated with an increase of blood flow and oxygen and an immediate release of glucose. This would make our ancestor better equipped physiologically to fight the bear or run away from it than if she had been indifferent or pleasantly relaxed.
Although we experience fear in response to things that are inherently dangerous today, we also sometimes experience a longer-lasting fear in response to the pressure and new standards of success imposed on us by modern culture. However, the fact that emotions and foods we experience today are partly influenced by the civilization we live in does not undermine its biological and evolutionary basis. The changes environmental pressures may trigger more intense or longer-lasting neurochemical responses of the same sort that caused the moods and emotions of our ancestors. Owing to the health consequences of intensified or longer-lasting these neurochemical responses, having the neurobiological systems that helped our ancestors may no longer be an evolutionary benefit for us. But it may take evolution ages to weed out the genes that generate this kind of extreme stress sensitivity in many modern humans.
The upshot is that while the emotions and moods we see examples of today may no longer be evolutionarily beneficial, they may the result of neurobiological responses that are very similar to neurobiological responses that once were advantageous in environments that were not continually putting pressure on us to perform beyond capacity.
Classification of Emotions: Valence and Arousal
Moods and emotions can be characterized along two dimensions: valence (sometimes scores on a positive-negative or pleasure–displeasure scale) and degree of arousal (sometimes scored on a activation-deactivation or engagement–disengagement scale). The valence of an emotion or mood pertains to the cognitive interpretation of the physiological responses. The degree of arousal of an emotion or mood pertains to the degree of activation of the autonomic nervous system--the control system that regulates automatic bodily functions such as heart rate, arterial response, digestion, urination, pupillary response and sexual arousal. It is this part of the body’s nervous system that controls our fight-or-flight response, discussed earlier.
Positive-valence and high-arousal affective states include feeling sexual attracted, in love, euphoric and enthusiastic. Positive valence-low arousal states include feeling appreciative, relaxed, complacent and sexual satisfied. Negative valence and high arousal are characteristic of feeling afraid, disgusted, angry, suicidal, hurt, and jealous. Negative valence and low arousal are typical features of feeling depressed, melancholic, lonely and helpless. Here is a quick overview of a limited selection of emotions/moods in the four quadrants yielded by the valence-arousal principles of categorization:
High Arousal Low Arousal
Positive Valence Enthusiastic Appreciative
Negative Valence Tyrannic Bored
Annoyed Emotionally hurt
The valence and arousal effect of emotions and moods can both alter subjective feelings responsible for how we identify and name emotions as well as cognitive processes such as attention, memory, decision-making and problem solving.
Cultural Differences in Positive-Valence Emotions
An intriguing question that arises in this context is whether all emotions and moods witnessed today have an evolutionary basis or whether some are socio-cultural constructs. By ‘socio-cultural construct’ I mean that a physiological response (that is biologically based) is cognitively reinterpreted in light of the influences of modern culture or historically significant events. Such a reinterpretation of a physiological response would likely be felt entirely differently on a subjective level and would give rise to a different pattern of behavior than the alternative cognitive interpretation. As a result, it would lead us to identify the response together with the new cognitive interpretation as a new emotion.
Consider first positive-valence (high pleasure) emotions, such as feeling grateful, appreciative, sexual aroused, sexual satisfied, in love, curious, relaxed, serene, rejuvenated, euphoric, enthusiastic, adventurous, innovative, or triumphant. Among the multiplicity of positive-valence emotions, what is considered the ideal emotions/moods that people strive to experience and act on and admire in others varies across history and culture. Because people’s ideas about what counts as an ideal emotion motivates them to aim at engaging in certain kinds of behavior and avoid others, their attitudes toward positive-valence emotions/moods may have quite significant impacts, not only on how individuals behave on a daily basis, but also on long-term happiness and the structure of society in ethical, legal, political, economic and social arenas.
Recent research into East-West cross-cultural differences indicates that these predictions are borne out. Differences in attitudes in Western individualistic cultures versus Eastern collectivist cultures--a relatively new development as far as evolution goes--may have led to different cognitive interpretations of physiological responses and hence may have produced differences in what we admire in others and thrive to achieve.
In Eastern collectivist culture, positive low-arousal emotions are held in higher esteem than positive high-arousal emotions, which motivates a desire to manifest and act on low-arousal psychological states and avoid expressing high-arousal affect. With a focus on being solemn and reserved as well as connected to and interdependent on others, happiness and life satisfaction are equated with more serene, holistic and other-directed emotional states and a wish to act accordingly.
In Western individualistic culture, by contrast, positive high-arousal emotional states, such as feeling driven, goal-oriented and expansive, are held in higher esteem by Westerners and are subject to considerably greater admiration than positive low arousal emotions. Happiness and life satisfaction are equated with the possession of those goal-oriented and self-congratulatory emotional states. As a consequence, Westerners strongly desire to manifest and act on such self-directed attitudes, and they are frequently admired in others.
The difference in emotional preference can be traced back to the value assigned to subject-centered concepts, such as autonomy, talent and achievement. Subject-centered concepts form the basis of the fundamental ideology of Western culture. Indeed, our convictions about what will make us happy stem in large part from the embodiment of such concepts in all aspects of Western society.
Western and Eastern cultures prevent lurking challenges to their ideologies in a number of ways. Caregivers instruct or coerce their children to participate in activities that are likely to elicit the positive emotions that are valued in society, for instance, arousal eliciting games and sports in the West. In more recent times, the more affluent among parents also stay in the proximity of their children and plow the way for them to be on the right path toward an economic class populated by teachers, colleagues, employers, bosses and politicians who admire and encourage the culture’s existing affective ideals. The “snow plows,” “tiger moms,” and “helicopter parents” who help keep the culture intact reinforce the cultural ideologies by withdrawing the privileges of those who stray or by issuing threats or demand participation in mind-numbing drills.
Paradoxically, the tendency to overvalue a particular class of positive emotions by plowing, imprisoning and threatening as the new style of education triggers a tendency toward greater negative low-arousal emotions. In Western civilizations, in particular, it cultivates feelings of confusion about one’s belonging and identity, ostracization by hostile work environments, fear of failure to meet expectations to be industrious, competitive, driven, perfectionistic, confident and independent as well as pressure to comply with our society’s ideological approach to life satisfaction, happiness, well being and flourishing.
Brogaard, B. (2015). On Romantic Love: Simple Truths about a Complex Emotion, New York: Oxford University Press.
Ekman, P. (1992). “An Argument for Basic Emotions,” Cognition and Emotion 6, 3-4, 169-200.
Ekman, P. & Friesen, W.V. (1971). "Constants Across Cultures in the Face and Emotion," Journal of Personality and Social Psychology 17: 124–129.