nature of emotions

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Almost everyone agrees that thestudy of emotion is one of the most

confused (and still open) chapters in thehistory of psychology. By one estimate,more than 90 definitions of “emotion”were proposed over the course of the20th century. If there is little consensuson the meaning of the term, it is no won-der that there is much disagreementamong contemporary theoreticians con-cerning the best way to conceptualizeemotion and interpret its role in life.

In everyday human existence we con-ceive of an emotion—anger, despair, joy,grief—as a feeling, an inner state. The in-ternal experience of emotion is highlypersonal and often confusing, particular-ly because several emotions may be ex-perienced at the same time. Imagine,then, how difficult the objective study ofemotion must be. Most of us often censorour own thoughts and feelings, and wehave learned to be cautious about ac-cepting other people’s comments abouttheir feelings. The empirical study of apsychological phenomenon so complexand so elaborately cloaked cannot helpbut present a special challenge.

Compounding the distrust of verbalreports of emotion are the influences ofbehaviorism and psychoanalysis on psy-chological research. The behaviorists ofthe 20th century believed that the onlytruly reliable, objective information ob-tainable from living creatures was infor-mation about their behavior. A classical

behaviorist would hold that emotion isan inner state and thus simply outsidethe realm of science. For their part, psy-choanalysts have made us aware thatemotions may be repressed, inhibited orunconscious, and thus unavailable to in-trospection. Finally, language itself intro-duces ambiguity and does not make iteasy to describe mixed emotions in anunequivocal way. The meaning of emo-tion terms is often obscure. For example,many people are not sure about the dif-ferences between fear and anxiety, guiltand shame, or envy and jealousy. As aresult, we often resort to metaphor to at-tempt to describe emotion. Think, for ex-ample, of such expressions as “blowingoff steam,” “hating someone’s guts,”“pain in the neck,” “lump in the throat”and “a broken heart.”

How, then, can emotion be studiedand understood? The challenge of devel-oping a theoretical approach is impor-tant, because emotions are an essentialpart of who we are and how we survive;emotional distress impels people to seekhelp, and indeed the primary concern ofpsychotherapy is the repair of emotionaldisorders. To simply declare emotionoutside the bounds of scientific studywould be irresponsible.

I believe that a scientific and therapeu-tically useful understanding of emotionsis possible. In fact, there are several sci-entific intellectual traditions that havedealt with this issue. There are an evolu-tionary (launched by Charles Darwin), apsychophysiological (William James), aneurological (Walter Cannon) and a psy-chodynamic tradition (Sigmund Freud),in addition to the cognitive perspectivethat began emerging in the 1950s. Morerecently neurobiological evidence has be-gun to inform the discussion; however,identifying the structures of the brain re-lated to emotion is not a theory of emo-tion, nor can such a theory be built froma knowledge of the chemicals involved

in mood states, just as an adequate theo-ry of depression cannot be constructedsimply from a knowledge of the avail-ability of serotonin. As the University ofIowa neuroscientist Antonio Damasiohas pointed out, when the amassing ofdata does not resolve a complex issue, itmay be necessary to find new ways toconceptualize the problem.

In my view evolutionary theory pro-vides a way to unify a number of theo-retical perspectives. Using the tools andmethods of evolutionary biology, andpulling together information from otherspecies, we can put emotions in a func-tional framework—define them in termsof what their adaptive function might be,and thus understand better their biologi-cal basis and the apparent connectionsbetween them.

Some work along these lines has beenwidely popularized in recent years: Bynow we’ve all heard authors of best-sell-ing books describe jealousy, love, anxi-ety and fear in dogs, cats, chimpanzees,baboons, elephants and lions. The bes-tiaries of the medieval period containeddetailed descriptions of emotions in ani-mals. The popular appeal of such expla-nations may lie in their ability to touch adeep-seated sense of the connectednessof all living things. Although many psy-chologists have warned of the dangersof anthropomorphism, recent thinkingby cognitive scientists and others seesthis attitude as an outdated prejudice.The Rockefeller University zoologistDonald Griffin, one of the founders ofthe field of animal cognition, believesthat the “charge of anthropomorphismis a conceited claim that only ourspecies is capable of even the simplestconscious thinking.” But there is dan-ger in oversimplifying: A sophisticatedunderstanding is needed to inform clin-ical practice.

Over the past four decades I havepulled together evidence from various

344 American Scientist, Volume 89

The Nature of Emotions

Human emotions have deep evolutionary roots, a fact that may explain their complexity and provide tools for clinical practice

Robert Plutchik

Robert Plutchik is professor emeritus at the AlbertEinstein College of Medicine and adjunct professorat the University of South Florida. He received hisPh.D. from Columbia University. He has authoredor coauthored more than 260 articles, 45 chaptersand eight books and has edited seven books. Hisresearch interests include the study of emotions,the study of suicide and violence and the study ofthe psychotherapy process. Address for Plutchik:4505 Deer Creek Boulevard, Sarasota, FL 34238.Internet: [email protected]

© 2001 Sigma Xi, The Scientific Research Society. Reproductionwith permission only. Contact [email protected].

studies to form a psychoevolutionarytheory of emotion, with the goals of clar-ifying what emotions are, finding waysto measure them, relating emotions toother psychological disciplines, and in-forming the practice of psychotherapy.Like many concepts in science, emotionscan be best understood by making infer-ences from certain classes of evidence.Such inferences suggest that emotions ortheir evolutionary precursors (or proto-types) can be found among lower ani-mals as well as human beings, a fact thatcan provide fascinating evolutionary in-sights into our emotions, moods andpersonality traits. They suggest furtherthat emotion, cognition and action inter-act in feedback loops and that emotioncan be viewed in a structural model tiedto adaptation.

Evolution and EmotionWhat we call cognition—the activity ofknowing, learning and thinking, ofwhich emotion is a part—evolved overmillions of years. Charles Darwin recog-nized that the process of evolution bynatural selection applied not only toanatomic structures but also to an ani-mal’s “mind” and expressive behav-ior—a conclusion that led him to write abook on emotional expression. Thosewho have followed Darwin in studyingthe evolutionary origins of emotionhave sought to understand how emo-tions increase evolutionary fitness forthe individual.

As mentioned above, a few evolu-tionary origins are easy to postulate.Fear and anxiety in people closely paral-lel the state of heightened arousal of an

animal who senses a predator or a threatto its offspring, a similarity that has beenfound in neurochemical, anatomical andimaging studies that show these statesare mediated by the limbic system, thepart of the central nervous system com-mon to lower and higher animals. Loveand emotional attachment clearly pro-mote pair bonding, reproduction andparental investment, basic to evolution-ary fitness in human beings. But the ori-gins of some other emotions are harderto find. Is there a general principle thatcan be applied?

The place to start might be with the de-finition problem. An emotion is not sim-ply a feeling state. Emotion is a complexchain of loosely connected events that be-gins with a stimulus and includes feel-ings, psychological changes, impulses to

2001 July–August 345© 2001 Sigma Xi, The Scientific Research Society. Reproduction

with permission only. Contact [email protected].

Figure 1. Great egrets in breeding plumage fight in midair, displaying the agonistic behavior that is the precursor of human emotions such as fear,anger and jealousy. Human emotions, says the author, are best viewed through an evolutionary lens, as adaptations triggered by the challenges ofsurvival and reproduction that are part of every organism’s existence. An evolutionary approach, he argues, can sort out the roles of emotion, impulseand action and, in a therapeutic setting, help people understand the circumstances in which emotions can sometimes fail in their adaptive tasks.

Carl Sams II/Peter Arnold, Inc.

action and specific, goal-directed behav-ior. That is to say, feelings do not happenin isolation. They are responses to sig-nificant situations in an individual’s life,and often they motivate actions. This de-finition of emotions allows the conceptto be generalized to lower animals with-out difficulty. From his studies of ani-mals, human infants and human adults,Darwin concluded that expressive be-

haviors communicate information fromone animal to another about what islikely to happen; therefore they affect thechances of survival of the individualdemonstrating the behavior. “Even in-sects,” he wrote in his 1872 book, “ex-press anger, terror, jealousy, and love bytheir stridulations.”

Extending Darwin’s idea a bit, I pro-pose that in general, emotions are acti-vated in an individual when issues ofsurvival are raised in fact or by implica-tion. Such situations include threats, at-tacks, poisonous substances or thesighting of a potential mate. The effectof the emotional state is to create an in-teraction between the individual andthe event or stimulus that precipitatedthe emotion. The interaction usuallytakes the form of an attempt to reducethe disequilibrium and reestablish astate of comparative rest.

Protozoologist Nicola Ricci of theUniversity of Pisa in Italy pointed outin 1990 that every single-celled organ-ism, from the blue-green alga to the eu-karyote, is a complete, self-sufficient or-ganism. Single-celled organisms areexposed to daily risks in their environ-ments. They take in food, excrete wasteproducts, avoid predators, reproduceby exchange of genes in many cases,seek safe environments and exploretheir microbiological world. Thus thesesimple organisms adapt to many of thesame problems as higher, multicellularorganisms. Bacteria are capable of verycomplex metabolic pathways, and, as

Ursula Goodenough detailed in thesepages in 1991, viruses and bacteriahave evolved tactics of camouflage, dis-traction and mimicry. Even plant cellssuch as green algae show defensive re-actions to touch, and chemical mes-sages signal everything from alarm tosexual attraction in organisms frombacteria to human beings.

As one moves up the evolutionaryladder, it is remarkable to note that asmall number of developmental genescan radically alter the behavior of cellsand change an amoeba into a multi-celled organism. Developmental biolo-gist William Loomis of the University ofCalifornia, San Diego, estimated in 1988that “the important evolutionary differ-ences between a guppy and a primateprobably lie in only a few hundredgenes.” Along with the genetic continu-um, and evolutionary continuities instructure, function and development,then, it is not surprising that one can dis-cern a behavioral continuum.

Writing in 1980, the late zoologistJohn Paul Scott of Bowling Green StateUniversity pointed out that it is the na-ture of the environment that creates cer-tain functional requirements for all or-ganisms if they are to survive. LikeRicci’s alga, a higher organism must takein nourishment and eliminate wasteproducts. It must distinguish betweenpredator and prey and between a poten-tial mate and a potential enemy. It mustexplore its environment and orient itssense organs appropriately as it takes ininformation about the beneficial andharmful aspects of its immediate world.Organisms that are relatively helpless atbirth must have ways of indicating theneed for care and nurturance.

Only a few classes of adaptive behav-ior, Scott noted, are found in mostspecies and at most phylogenetic levels.These include eating, the fight-or-flightresponse, sex, caregiving and investiga-tion. These patterns might be consid-ered prototype adaptations. The con-nections between behavior and innerstates and processes are less obvious.Yet such connections can be made by in-ference from a variety of evidence. Thisevidence includes knowledge of stimu-lating conditions, the effects of behav-ioral acts, knowledge of typical behav-ior patterns of the individual andspecies, choices made when alternativesexist and reactions of other members ofone’s group or species. A single overtdisplay of emotions can reflect complexstates such as approach and avoidance,

346 American Scientist, Volume 89© 2001 Sigma Xi, The Scientific Research Society. Reproduction


Figure 2. Microorganisms—here a paramecium, mixed algae, diatoms and other plankton—takein food, excrete waste products, avoid predators, reproduce, seek safe environments and exploretheir world. They must distinguish between predator and prey and, if their mode of reproduc-tion requires it, between a potential mate and a potential enemy. This information-gatheringand prediction and other universal adaptations found in all organisms constitute prototypeadaptations from which human emotion can be modeled.

Figure 3. Suckling her young, a suricatemeerkat mother keeps an eye on her sur-roundings in a South African nature preserve,ready to protect her offspring from any threat.Psychologists believe cognitive functionsevolved to serve emotional and biologicalneeds—in evolutionary terms, in order to pre-dict the future more effectively. In survival sit-uations cognitions and inner states such asarousal tend to be followed by impulses to ac-tion—perhaps, in this case, a defensive or pro-tective posture, attack or flight.

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attack and flight, sex and aggression, orfear and pleasure. It is not necessarilyeasy to detect an emotional substrate inthe behavior of lower animals, but nei-ther is it necessary to exclude the possi-bility. Emotion is far more complex thanthe subjective experience familiar to ahuman adult, and the concept of emo-tion can be applied to lower animals aswell as human beings. Emotions havean inherent complexity that is in part re-lated to their evolutionary history.

Cognition, Emotion and EvolutionAny organism must determine, on thebasis of limited information, whetherthere is food, a mate or danger in its en-vironment. Depending on the predic-tion made, the organism makes a deci-sion to escape, to attack, to eat or tomate. The complex processes that go onin the service of biological need includereceiving sensory input, evaluating it,capturing the important aspects of theinformation in symbols and comparingthe new information with memorystores. Predicting the characteristics of

environments enables organisms toprepare for those environments.

Psychologist Ulric Neisser of CornellUniversity compared human beingswith computing machines in a seminalarticle in 1963. He suggested that cogni-tive functions serve emotions and bio-logical needs. Information from the en-vironment, he says, is evaluated in termsof its ability to satisfy or frustrate needs.What is particularly significant is thateach new cognitive experience that is bi-ologically important is connected withan emotional reaction such as fear, plea-sure, pain, disgust or depression. Fromthe point of view of evolution, cognitiondeveloped in order to predict the futuremore effectively. The human brain,which has evolved as an adaptation tochanging and difficult environments,has now helped create the very environ-ment to which it must continue to adapt.

If emotion is a chain of events, cogni-tion is generally near the beginning ofthe chain. This is considered an impor-tant point in the psychological commu-nity, which has put a good deal of effort

into answering the “what comes first?”question, ever since the American psy-chologist-philosopher William James in1884 framed the question this way: Is itthe feeling of emotion or the physiolog-ical changes that are part of emotion?This is actually a pseudoproblem.Emotions are not simply linear events,but rather are feedback processes. Thefunction of emotion is to restore the in-dividual to a state of equilibrium whenunexpected or unusual events createdisequilibrium. Even if cognitions aregenerally at the beginning of the chainof events, they can be influenced byevents appearing later in the chain—states of arousal, say, or ego defenses—through a feedback process. Stimulusevents, either external or internal (as indreams), act as primary triggers thatstart the emotion process going.

The biological aspects of this processhave been the subject of considerablerecent study. Animal research byJoseph E. LeDoux of New York Univer-sity has revealed that the conditionedfear response involves several neural



Figure 4. Feedback loops in emotion show how sensory information is evaluated and translated into action or some other outcome that nor-malizes the relationship between the individual and the triggering event. The inner state perceived as fear may arise from a threat that is per-ceived as “danger”; the fear triggers an impulse to flee, which results eventually in reduction of the threat. A similar set of homeostaticprocesses can be seen in the case of sadness in a child experiencing loss of her mother.

feelingstate

physiologicalarousal

effectstimulus event

inferred cognition

impulses to action

overt behavior (displays)

fearprotect

from attackthreat bypredator danger

increasedautonomic

activity

impulseto run

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reductionof threat

no danger

relaxation

impulse tostop running

stop running

sadnessdistress reattach

to lostmother orsubstitute

loss ofmother abandonment

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fear

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pathways with different latencies.Damasio has traced the events in an ini-tial defensive response (fear): The keyfeatures of a dangerous animal orevent—perhaps color, speed of move-ment, certain sounds—are detected andsignaled to the amygdala, a part of thelimbic system deep in the brain. Thisprocess is very rapid and is not a con-scious one. Signals from the amygdalato prefrontal areas and other locationsprecipitate the conscious feelings asso-ciated with an emotion.

Feeling states tend to be followed byimpulses to action. Emotion can causeone’s muscles to tense; it can be ex-pressed as a facial gesture, clenched fistor an action such as running, attacking oryelling. Impulses to action are not alwaysfollowed by action, as clinicians know—often for fear of retaliation or embarrass-ment. Even when they are, overt behav-ior is not the end of the emotion process.

Such behavior generally has an effecton the stimulus or condition that startedthe chain of events in the first place. Forexample, running from a source ofthreat reduces the threat and tends toreestablish the condition that existed be-fore the threat. Similarly, if someone los-es a parent, crying and grieving tend toelicit supportive and helpful contactsfrom members of the grieving person’s

social group and, at least in a symbolicway, provide a sort of reattachment withthe lost parent and thus a change in thefeeling state.

Overall, emotion is a kind of homeo-static process in which behavior medi-ates progress toward equilibrium; I callit a behavioral homeostatic, negative-feedback system. Emotion is a chain ofevents made up of feedback loops. Feel-ings and behavior can affect cognition,just as cognition can influence feeling.

At the heart of all these descriptions isthe idea that emotions have a function inthe lives of individuals. This idea arisesfrom an evolutionary perspective, is con-sistent with psychodynamic thinking andis becoming increasingly accepted in con-temporary writings. For example, youngorganisms require food, protection andtransportation. Crying is a major methodfor getting such care. Fear protects theself, initiates withdrawal and allows gen-eral functioning to continue. Shame leadsto remorse and a decrease in the proba-bility of repetition of the shameful act.

These examples imply that emotionsare part of a social regulation process.Evolutionary theory reminds us that theinterests of different individuals are of-ten in conflict: males versus females,parents versus children, brothers versusbrothers, group versus group. Genes are

“selfish” and concerned with self-main-tenance and self-reproduction. Social in-teractions and communications reflectthis conflict. Listening and speaking areregulated by direct and subtle expres-sions of emotion—smiles, eye contact orlooking away, nods, postural shifts, vo-calizations, passive questions and im-plicit commands (“Why don’t you weara hearing aid?”).

Much social interaction involves in-dividuals in different hierarchical po-sitions. In such situations, during con-versation there is often a censoring ofrebellious thoughts, and a covert compe-tition of ideas. An individual may expe-rience feelings of defiance or may accepta submissive position. Emotions, at bothconscious and unconscious levels, regu-late such social processes.

Another way to conceptualize emo-tions as a social-regulation process is interms of the views of animal communi-cation proposed by Eugene Morton ofthe Smithsonian Institution and his col-leagues. They point out that communi-cation is an assessment/managementprocess aimed at survival. Communica-tion signals are selected in evolution be-cause they substitute for more risky be-havior such as fighting.

California ground squirrels stimulatea rattlesnake to rattle by kicking earth atit. This is done because squirrels use thesound of rattling to assess the snake’ssize and body temperature, two factorsthat determine how dangerous thesnake is to their pups. With many ani-mals, distress calls are adaptive becausethey may startle a predator into lettinggo, may attract the attention of otherconspecifics to mob the predator, or mayattract a larger predator to compete andpossibly allow escape. However, it is notalways easy to determine the adaptivenature of a given signal.

Emotions are part of the managementof the process. Anger, for example, in-timidates, influences others to do some-thing you wish them to do, energizes anindividual for attack or defense andspaces the participants in a conflict.

Modeling the EmotionsI have used the term “emotion” as a sin-gle, general term for a group of phenom-ena. As complex processes with func-tional value both in communication andin increasing the individual’s chances ofsurvival, emotions represent proximatemethods to achieve evolutionary fitness.To integrate many of the things knownabout emotions, model-making is useful.



unexpected event stop

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abandonment crysadness

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behaviorfeelingstate effect

Figure 5. Although emotional substrates cannot always be discerned in the behavior of non-human animals, many stimuli are experienced by people and animals alike and result in pro-totypical behavior followed by, generally, the reestablishment of an equilibrium state thatmight not have been achieved without the impulse precipitated by the inner state. In humanexperience it is common to use the term “emotion” to describe the feeling state, but in factemotion is considerably more complex.

In English there are a few hundredemotion words, and they tend to fall intofamilies based on similarity. I have foundthat the primary emotions can be con-ceptualized in a fashion analogous to acolor wheel—placing similar emotionsclose together and opposites 180 degreesapart, like complementary colors. Otheremotions are mixtures of the primaryemotions, just as some colors are prima-ry and others made by mixing the pri-mary colors. Such “circumplex” model-ing can be used as an analytical tool inunderstanding personality as well, andthe similarity between the two models isimportant. I have extended the circum-plex model into a third dimension, rep-resenting the intensity of emotions, sothat the total so-called structural modelof emotions is shaped like a cone.

The notion of a circumplex model isnot my invention, nor is it new. Socialpsychologist William McDougall notedthe parallel between emotions and colorsin 1921, writing that “the color sensationspresent, like the emotions, an indefinitelygreat variety of qualities shading into oneanother by imperceptible gradients….”The first circumplex model was one de-veloped by Brown University psycholo-gist Harold Schlosberg in 1941, after hehad asked research participants to judgethe emotions posed in a standard set ofpictures of facial expression. Schlosbergadded the intensity dimension to hismodel. My own model was proposed in1958, when I suggested eight basic bipo-lar emotions: joy versus sorrow, anger ver-sus fear, acceptance versus disgust and sur-prise versus expectancy.

Over the centuries, from Descartes tothe present, philosophers and psycholo-gists have proposed anywhere from 3 to11 emotions as primary or basic. All thelists include fear, anger and sadness; mostinclude joy, love and surprise. There is nounequivocal way to settle on a precisenumber, although factor-analytic stud-ies, similarity-scaling studies, child-de-velopment studies and cross-culturalstudies are useful. But in the final analy-sis, this is a theoretical decision to be



serenity

joy

ecstasy

acceptance

trust

admiration

interest

anticipation

vigilance

annoyance anger rage terror fear apprehension

loathing

grief

amazement

disgust

sadness

surprise

distraction

pensiveness

boredom

aggressiveness awecontempt

submission

rem

orse

love

optimism

disapproval

Figure 7. To help psychologists understandthe relations among emotions, raters wereasked to estimate the degree of similarity be-tween certain pairs of emotions. The use of asimilarity scaling method produced the em-pirical angular locations shown in the figure(where opposites have a similarity ranking of–1.0 and identical concepts have a similarityranking of 1.0). The concepts shown are a se-lection from a larger population of words.

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Figure 6. Author’s three-dimensional circumplex model describes the relations among emotionconcepts, which are analogous to the colors on a color wheel. The cone’s vertical dimension rep-resents intensity, and the circle represents degrees of similarity among the emotions. The eightsectors are designed to indicate that there are eight primary emotion dimensions defined by thetheory arranged as four pairs of opposites. In the exploded model the emotions in the blankspaces are the primary dyads—emotions that are mixtures of two of the primary emotions.

evaluated in terms of the inferences andinsights to which it leads, the research itsuggests and the extent to which empir-ical data are consistent with it. The psy-choevolutionary theory assumes thereare eight basic emotion dimensionsarranged in four pairs.

If there are eight basic emotion dimen-sions (each with a number of synonymsor related terms), how can we accountfor the total language of emotions? Vari-ous published studies imply that the fewhundred emotion words tend to fall intofamilies based on similarity. If we followthe pattern used in color theory and re-search, we can obtain judgments aboutcombinations—the emotions that resultwhen two or more fundamental emo-tions are combined, in the same way thatred and blue make purple. Judges inthese studies have agreed that mixing joyand acceptance produces the mixed emo-tion of love; disgust plus anger produceshatred or hostility. Such mixtures havebeen called primary dyads in the theory.One can continue on this way and ac-count for hundreds of emotion terms bymixing two or more emotions at differ-ent levels of intensity.

As noted above, it is interesting andperhaps important that one of the hy-potheses generated from this structuralmodel is that personality traits shouldhave a similar structure. Again we cantake cues from language. Although per-sonality is usually taught in universitiesas if it had little or nothing to do withemotions, words such as gloomy, resent-ful, anxious and calm can describe person-ality traits as well as emotional states. Anindividual can feel depressed, or be a de-pressed person, feel nervous or be a ner-vous person. Often people are able tomeasure both emotional states and per-sonality traits using the same checklist ofadjectives, with a simple change in in-structions. When research participantsare asked how they feel now, or withinthe past few days, the instruction asksfor a self-report of an emotional state or amood. But they can be asked how theyusually feel, a question that yields infor-mation about personality traits. At theextremes are pathological states such asmania and paranoia—but even these canbe conceived as extreme expressions ofsuch basic emotions as sadness, joy anddisgust. Thus personality traits may beconceptualized as being derived frommixtures of emotions. With my colleagueHope Conte, I have been able to find acircumplex structure for certain classesof personality traits.

Furthermore, in recent years therehave been more than 100 publishedstudies concerned with identifying per-sonality characteristics in lower ani-mals. Of course lower animals probablyshould be said to have temperamentrather than “personality,” but extraver-sion, emotional stability and agreeable-ness have shown considerable generali-ty across species. Samuel Gosling of theUniversity of Texas at Austin and OliverJohn of the University of California,Berkeley, have identified extraversionand emotional stability as characteris-tics of animals as low on the phyloge-netic scale as guppies and octopuses.

Some ImplicationsAn evolutionary framework suppliesthe study of emotions with such con-cepts as functional thinking, the gener-ality of mechanisms across phyla, de-velopmental theory (to explain, forinstance, attachment), and the conceptsof inclusive fitness and proximate andultimate causation.

Happily, in combination with the se-quential, structural and derivative sys-tems described above, evolutionary the-ory can provide not only a way oforganizing data in the fields of emotion,personality and psychopathology, butalso new tools for clinical practice.

A therapist must uncover and identi-fy emotions. An evolutionary approachsuggests that the subjective feeling statesof emotion (the labels they are given) areusually more ambiguous and obscurethan are the associated impulses to ac-tion. We need not insist like the behav-iorists that only overt behavior is suit-able for study; however, impulses toaction may be probed whether or notthe action takes place.

In addition, successful adaptation im-plies the ability to feel and express allemotions in appropriate settings. Appliedto emotion, the societal dictate that “thereis a time and a place for everything” ac-tually encapsulates the idea that all emo-tions can be adaptive within human soci-ety. It is a matter of sorting out the specificcircumstances in which emotions cansometimes fail in their adaptive tasks

The psychoevolutionary theory hasguided the development of tests formeasuring moods, personality traits,ego defenses and coping styles. It hasalso proposed a connection betweenemotions and the existential crises thatall human beings are subject to—thoseinvolving hierarchy, territoriality, identi-ty and temporality.

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