Evolutionary psychology offers a powerful framework for understanding the ultimate function of emotions, and that understanding can be applied usefully in the mediation context. In this article, we first introduce the relevant theoretical foundational assumptions of the evolutionary approach to emotions and then use anger and gratitude to illustrate the evolved functions and effects of emotions on cognition and behavior before exploring specific implications for mediation. We also discuss mediator strategies for leveraging anger and gratitude, as well as the potential for future research applying an evolutionary approach to understanding emotions in mediation.

We all know that emotions are useless and bad for our peace of mind and our blood pressure.

– B.F. Skinner (1948: 92)

A plaintiff punctuates his statement by slamming his fist against the table. A defendant raises her voice in denial. Another disputant reaches for tissues to stem the tide of tears. No matter the basis for dispute, mediators are accustomed to the expression of emotions throughout the dispute resolution process. Indeed, mediation experts note that strong emotions are a fundamental component of the conflict experience (Jones 2001; Frenkel and Stark 2012). Emotions affect our physiology (e.g., heart rate, body temperature), cognition, and behavior. As such, emotions may act as psychological barriers to settlement (Frenkel and Stark 2012). Emotions, however, can also facilitate agreement (Adler, Rosen, and Silverstein 1998). Thus, fluency in understanding emotions and how they are expressed can help mediators to identify underlying interests, keep the conversation productive, and guide participants toward resolution.

Although previous scholars have acknowledged the importance of emotions in dispute resolution, in this article we suggest that evolutionary psychology can illuminate the function of emotions and their application in the mediation context. An evolutionary psychological approach posits that emotions represent psychological adaptations, which can have significant implications for social interaction (Cosmides and Tooby 2000). Additionally, evolutionary psychological theorists propose that different emotions address the functionally distinct and recurrent challenges and opportunities that our human ancestors faced, facilitating their reproductive success across a range of functionally distinct contexts (Nesse 1990). Thus, they expect the purpose of each emotion, as well as the ways in which people express it, to differ: each emotion has a different purpose and the utility of its expression changes according to the situation (Lazarus 1991). According to evolutionary psychology, emotions evolved as coordinated responses to predictable stimuli – for example, people respond with fear to a threat to their physical safety, with disgust to a threat to their health. Importantly, this adaptationist framework suggests that emotions and emotional expressivity are functional, rather than irrational, and predictable, rather than arbitrary.

Evolutionary psychology has sought to explain a wide range of human psychology and behavior, including mate preferences, stereotyping and prejudice, health behaviors, social influence, and financial decision‐making (Neuberg, Kenrick, and Schaller 2010). Mediation scholars have not yet applied this theoretical approach to the mediation context; doing so, we argue, can help mediators better understand and respond to their clients’ expressions of emotion.

In this article, we apply the evolutionary perspective to emotions in mediation, focusing on anger and gratitude as examples. We describe the evolved functions of these emotions as well as their effects on cognition and behavior. We also examine their specific implications for mediation and identify several potential mediator strategies for dispelling – or leveraging – outbursts. Ultimately, we seek to introduce mediation scholars to the evolutionary framework and to encourage additional exploration and discussion of its utility within the context of mediation and other conflict resolution processes.

Whether conveyed by facial expression, tone of voice, word choice, or body posture, emotions in mediation are often easily recognizable and play a critical role in how disputants respond to conflict. Mediation experts have long acknowledged the emotionality of conflict, and have argued that being aware of and embracing emotion is critical to successful dispute resolution (Golann and Folberg 2011; Lieberman 2012; Moore 2014). Some scholars have suggested that emotions generally arise as a result of parties’ incompatible positions and needs, and act as motivating forces for the pursuit of important goals (Adler, Rosen, and Silverstein 1998; Frenkel and Stark 2012). Some contend that emotional expression serves an important venting function, allowing the parties to convey key interests and clear their minds, and is a component of the “healing process” (Moore 2014: 139). This cathartic effect helps parties to resolve inner conflict, so that mental abilities and energies can instead be focused on external conflict (i.e., the dispute at hand).

Conversely, suppressing or refusing to address emotions may perpetuate and even intensify negative emotions by causing individuals to mentally rehearse and relive negative experiences (Jones 2001). Such censorship is seldom effective because unexpressed emotions seep into the conversation, affecting the suppressing party’s tone of voice, body language, facial expression, and listening ability (Stone, Patton, and Heen 1999). In the dispute resolution context, ignoring feelings can result in unsatisfying outcomes that fail to address the root cause of the conflict and underlying needs of the parties (Golann and Folberg 2011). Thus, some mediation experts advise tackling emotions head‐on, but stress that the mediator needs to tailor her response to the specific emotion expressed (Lieberman 2012). Sadness may be best met with empathy, such as verbal expressions of acceptance (“It’s O.K. to cry”; “I can understand how you feel”), and, under appropriate circumstances, physical contact (patting the shoulder; briefly touching the hand). Anger, while also productively met with empathy and acknowledgment (“That sounds pretty frustrating”), necessitates a response that is calm, yet firm. According to this thinking, remaining composed will elicit reciprocal behavior from the angry party and help return her or him to a calmer emotional state (Lieberman 2012).

In contrast, other experts suggest addressing core needs and interests rather than focusing on the expressed emotion itself. Roger Fisher and Daniel Shapiro (2005) argued that dealing directly with emotions is complicated, given the difficulty in accurately identifying and managing the many emotions that people experience. Instead, these authors suggest that many of the emotions that disputants express reflect five underlying core concerns: appreciation, affiliation, autonomy, status, and role. When these needs are unaddressed, emotions commonly viewed as negative arise; when they are addressed effectively, the parties are more likely to experience emotions typically seen as positive (Fisher and Shapiro 2005). Thus, the authors suggest that attending to these core concerns can enable the mediator to better understand the emotional experience of the parties and help generate more desirable emotions.

Regardless of whether mediators first focus on the specific emotions or the underlying needs that drive them, mediation scholars agree that acknowledging, rather than ignoring, emotions is critical because of emotional arousal’s cognitive and behavioral effects (Golann and Folberg 2011; Moore 2014). Incorporating findings from social and clinical psychology, mediators have noted that certain emotional states can diminish individuals’ ability to think clearly and rationally, and interpret information objectively (Adler, Rosen, and Silverstein 1998). This resulting cognitive impairment can then escalate existing negative emotional states, creating an undesirable and unproductive feedback loop in which parties mentally rehearse negative emotions over and over, and develop “internal scripts” leading them to perceive others’ motives as entirely hostile (Frenkel and Stark 2012). Emotions can, however, also play a critical role in generating useful feedback – signaling information about parties’ moods and willingness to agree that can then be incorporated into the mediator’s strategy for resolution (Adler, Rosen, and Silverstein 1998; Moore 2014).

Clearly, mediation theorists have recognized the importance of emotions in the mediation context – for providing insight to underlying interests, for creating psychological barriers to resolution, and even for facilitating agreement. But where do these emotions “come from?” In considering the sources of emotion, mediation scholars focus on proximate explanations – that is, the relatively immediate causes – of these emotions and disputants’ expression of them. For example, people get angry when they perceive wrongdoing, disrespect, untrustworthiness, or unfairness (Frenkel and Stark 2012). The few mediation scholars who have touched upon the evolutionary origins of emotions have done so with little depth, describing “negative” emotions as tools for survival. For example, Robert Adler, Benson Rosen, and Elliott Silverstein (1998) argued that fear helped ancestral humans avoid predation and suggested that emotions commonly viewed as negative carry greater “survival potential” than ones generally considered to be positive. We contend that a deeper understanding of the evolutionary perspective adds important nuance to our understanding of emotions in a mediation context.

“Evolutionary psychology” is a metatheoretical approach that examines psychological phenomena through the lens of natural selection (Neuberg, Kenrick, and Schaller 2010). An evolutionary psychological approach begins, first, with the assumption that much of human behavior ultimately serves a function: reproductive fitness, that is, the successful perpetuation of one’s genes into subsequent generations (Neuberg, Kenrick, and Schaller 2010). Behaviors are “functional” in the sense that they, and the psychological mechanisms that produce them, have had positive implications for reproductive fitness in the past. In other words, if the cognitive mechanisms underlying a behavior somehow gave at least some of our human ancestors a reproductive advantage then that behavioral tendency was passed on to offspring and perpetuated.

“In the past” is critical because psychological adaptations to ancestral environments may be maladaptive in contemporary environments. For example, in the relatively resource‐scarce ancestral environment, individuals exhibiting a preference for sugary and fatty foods – and who were thus more likely to gorge upon these calorie‐rich foods – were more likely to survive and reproduce, in turn producing offspring with similar inclinations to enjoy calorie‐rich foods (Neuberg, Kenrick, and Schaller 2010). In today’s resource‐rich environment, however, such an evolved preference may lead to over‐consumption resulting in obesity, diabetes, heart disease, and other illnesses (Fessler, Pillsworth, and Flamson 2004).

Importantly, reproductive fitness encapsulates more than the act of producing offspring (Kenrick et al. 2010). For example, one must survive to reproductive age by avoiding disease, predation, and other threats to physical safety. One must acquire and perhaps also retain a mate, which likely first involves gaining resources and status. And, after producing offspring, one must effectively care for those offspring until they reach reproductive age and can produce offspring of their own. Thus, successful reproductive fitness necessitates the navigation of multiple recurrent challenges and opportunities, going far beyond direct reproduction alone (Kenrick et al. 2010).

Evolutionary psychological theory posits that, through the process of natural and sexual selection, mental adaptations evolve to address recurrent challenges and opportunities for reproductive fitness. For example, just as physical features, such as eyelids, eyelashes, and tear ducts evolved to protect the eye and its critically important functions, psychological mechanisms also evolved to protect individuals from dangers and to facilitate achievement of reproductively relevant goals (Neuberg, Kenrick, and Schaller 2010). These psychological mechanisms may become activated in functional, context‐dependent circumstances such that specific social and environmental inputs trigger specific psychological and behavioral outputs. Thus, an evolved psychology – and human behavior more broadly – reflects ongoing interactions between the individual, the situation, and the environment, rather than genetically predetermined behavioral scripts (Neuberg, Kenrick, and Schaller 2010).

From an evolutionary psychological perspective, emotions are defined as superordinate cognitive mechanisms that coordinate and guide information‐processing programs (e.g., attention, perception, memory) and direct behavior, overriding (or simultaneously activating) programs within the mind specific to the relevant problem at hand (Tooby and Cosmides 1990; Cosmides and Tooby 2000). In other words, emotions have survival and reproductive functions.

Emotions are therefore discrete, elicited by different stimuli and serving different functions, and should not simply be categorized as either positive or negative (Griskevicius, Shiota, and Neufeld 2010; Shiota et al. 2011). Evolutionary researchers initially focused on a limited subset of emotions, so‐called “basic” emotions (e.g., fear, sadness, disgust) that are closely tied to survival and characterized as possessing distinctive universal signals (Ekman 1994). Recent work has broadened the classification to include any emotion that works as a superordinate coordination mechanism fitting the definition above (including, for example, romantic love, guilt, envy, and pride) (Al‐Shawaf et al. 2015).

Because emotions evolved to address distinct adaptive challenges, the physiological, cognitive, and behavioral effects of different emotions are equally distinct. For example, fear motivates self‐protection and thus physiological responses (e.g., increased heart rate) and behaviors (e.g., running away from the threat) that facilitate surviving dangerous circumstances (Cottrell and Neuberg 2005). Alternatively, sexual jealousy motivates mate retention and produces physiological responses and behaviors (e.g., increased attention and monitoring) that decrease the likelihood of a partner committing sexual infidelity and deter rivals from mate poaching (Goetz et al. 2008). Although both fear and sexual jealousy are thought of as “negative” emotions, they diverge in genesis, function, and outcome.

Emotions influence far more than downstream behavior. They also serve a coordination function: they shape individuals’ perceptions, memories, attention, communication, and learning; determine their priorities; and motivate their actions (Cosmides and Tooby 2000). This coordination is necessary given our various goals (e.g., self‐protection, mate acquisition) and finite cognitive and physiological resources to achieve them; for example, we cannot run away from a predator and engage in sexual intercourse at the same time (Kurzban et al. 2013; Patrick 2015). Emotions thus orchestrate the mind’s various tools to prioritize “the relevant ancestral goal over others … allocating the cognitive toolbox accordingly to place the mind and body in the best position possible to solve the [presenting] problem” (Patrick 2015: 14). In this respect, emotions may also serve a recalibration function, attuning the mind to relevant information that reweights or recomputes decision rules and priorities (Cosmides and Tooby 2000). For example, a coworker offers to pick up your shift so that you can attend your child’s birthday party. You likely experience the emotion of gratitude, and recalibrate the value you place in your coworker (e.g., “this is an important social relationship; I should behave in a way that protects and expands this relationship”).

Given the influence of emotions on individuals’ cognition and behavior, the ways in which we communicate our emotions and recognize those of others convey valuable information. Visual cues to emotion are largely salient and recognizable across cultures (Ekman 1994). For example, studies show that individuals from a wide range of cultures recognize expressions of anger to include a furrowed brow, whereas widened eyes and a lifted brow characterize surprise (Ekman 1994). Such detectable and distinguishable expressions are beneficial for communicating emotions, providing observers with useful information about an actor’s mental state, goals, and capacities. For example, anger cues may induce a target to correct his or her possible wrongdoing or avoid the angry individual, whereas displaying fear cues may communicate the danger to other in‐group members or kin. But communicating emotions can also entail risk. For example, anger expressions may provoke avoidance from not only hostile targets, but from desirable targets as well (e.g., potential mates, trading partners, friends), and fear expressions may signal weakness or vulnerability.

In sum, ancestrally recurrent cues elicit specific emotions, which in turn elicit behaviors intended to produce functional outcomes. Emotions orchestrate cognition, facilitate goals, and guide behavior. Emotions influence not just what we think, but how we think (Lerner and Tiedens 2006). They are a critical component of social interaction. The evolutionary perspective, as described above, highlights the richness and complexity of emotions. How might this perspective contribute to our understanding of emotional expressivity in the mediation context? The following section uses an illustrative example, anger, to explore the implications of evolved emotions for conflict and dispute resolution.

According to evolutionary psychology, each emotion evolved to solve specific recurrent, adaptive problems. The utility of expressing a particular emotion depends on the goals and capacities of the expresser and the particular challenge to be addressed. The same stimuli – for example, an alluringly dressed woman – may cue distinct emotional reactions depending on the goals of the perceiver, for example, romantic attraction on behalf of a man seeking a sexual partner, sexual jealousy on behalf of a woman concerned about her partner’s fidelity, or anxiety on behalf of a father worried that his daughter will attract undesirable attention.

Similarly, additional situational features influence the strength of the emotion and the likelihood that the person feeling it will actually express it in a noticeable way. So, in our example, the attracted man’s emotional expressivity may be very different depending on his proximity to the anxious father. Thus, considering emotions in mediation – and any context – necessitates a multi‐level inquiry: what is the function of the emotion? Under what circumstances is the emotion likely to be expressed, and by whom? In exploring these questions, we focus here primarily on the emotion of anger, which we have selected because it is ubiquitous in the conflict resolution context and has clear implications for mediation.

As discussed above, evolutionary psychologists are primarily interested in the evolved function of behavior, referred to as an “ultimate” level of analysis (Goetz et al. 2008). In contrast, most literature on emotions in mediation has focused on more immediate, “proximate” causes of behavior. Both analyses are important, and often produce compatible explanations. For example, we began this article with the image of an individual slamming his fist onto the table. A researcher might suggest that a proximate cause of the disputant’s behavior is “anger,” and perhaps that this anger was caused by the belief that a settlement offer he has just received was “unfair.” A researcher with an evolutionary perspective might agree, but this researcher might also ask: what is the function of anger? In other words, how might the experience of anger in specific contexts (e.g., when one believes she is being taken advantage of) have increased reproductive fitness in the past? And for which individuals are such expressions of anger most likely to be effective?

The Evolved Function of Anger

Anger is one of the most commonly felt emotions, with individuals reporting experiencing mild to moderate anger, on average, anywhere from several times a day to several times a week (Averill 1982). The emotion appears in infancy and is universally present across cultures (Sell, Tooby, and Cosmides 2009). The typical notion of anger is that it is an irrational, counterproductive, and destructive force (Fessler 2010). And indeed, anger can lead to many negative behaviors, including physical aggression, impulsivity, and carelessness (Lerner and Tiedens 2006). (We note, however, that from an evolved perspective, referring to behavior as “negative” does not imply a lack of functionality. Behaviors that are “negative” from a moral or social‐normative standpoint may nonetheless produce fitness‐enhancing outcomes.) Given the costliness of these behaviors, the species‐wide pervasiveness of anger strongly suggests that anger carried ancestral fitness benefits.

Evolutionary scholars studying anger support this proposition, arguing that the emotion serves multiple important, fitness‐enhancing functions. Anger activates a motivational system intended to overcome blocked goals, remove obstacles, and punish transgression, serving to resolve conflicts of interest in favor of the angry individual (Sell, Tooby, and Cosmides 2009; Fessler 2010). Although evolutionary psychologists generally agree as to these functions of anger, researchers have focused on different potential explanations as to the primary process motivating the experience and expression of anger. Some researchers suggest that anger’s key purpose is to motivate behaviors that stop ongoing transgressions and deter future transgressions (Fessler 2010). Transgressions, in this context, impose fitness costs (i.e., acts that lower an individual’s reproductive fitness) upon an individual against his or her will. From this perspective, these transgressions against the individual (or other people whom the individual values) elicit his or her anger, and he or she then behaves in a way intended to harm the transgressor. Because deterring future harm (from both the transgressing individual and other potential transgressors) is an important objective, anger responses may be disproportionately large when compared to the harm originally inflicted upon the individual (Fessler 2010).

Other evolutionary researchers have posited that anger serves the cognitive function of alerting us when others place insufficient weight on our welfare (Sell, Tooby, and Cosmides 2009). When someone behaves in ways suggesting that he or she places too little weight on another person’s interests, that person’s anger “program” is activated, leading to one of two tactics: inflicting costs (e.g., aggression) or withdrawing benefits. Psychologists have dubbed this the welfare trade‐off theory: anger motivates behaviors intended to recalibrate the value of a person’s welfare in the mind of the person who has angered her (Sell, Tooby, and Cosmides 2009). Cues to anger, therefore, communicate that the angry person will inflict costs or withdraw benefits unless the target places sufficient weight on her welfare.

How the target responds – whether he somehow expresses more consideration for the angry person’s welfare or not – depends on the potential fitness costs of doing that versus the relative fitness cost that might be imposed by the angry actor. For example, when an angry person is physically formidable and thus has significant potential to harm the target of his anger, recalibration may be more likely (Sell, Tooby, and Cosmides 2009). Conversely, when the target of the anger perceives she will receive few benefits by showing greater consideration of the angry person’s welfare (or incur few costs if she doesn’t), she is less likely to do so. In sum, these researchers suggest that the primary function of anger is to produce behavior that creates incentives for the target of the anger to visibly place greater weight on the angry individual’s welfare.

Because anger serves to deter transgression and to enhance others’ concern for one’s welfare, it follows that anger serves to protect one’s reputation (that is, the ways in which one is perceived by others). As social animals, our reproductive fitness and well‐being depend on our ability to successfully manage the perceptions and behavior of others (Neuberg and Cottrell 2008). When individuals place little value on our welfare and impose costs on our fitness, this also has implications for how others may behave toward us in the future, hence the impulse to go “overboard” to deter such behavior. Such responses attempt to reduce the likelihood that we will be transgressed against in the future. Anger thus helps people protect their reputations by motivating them to address, rather than ignore, the transgressions of others, even when doing so may put them at risk of harm.

Evolutionary scholars view anger as having evolved functions, assisting individuals with their pursuit and achievement of goals. In turn, the experience and expression of anger influences individuals’ cognition and behavior in important and dramatic ways.

Anger’s Influence on Cognition and Behavior

Anger is unique among the emotions commonly seen as negative, for several reasons. First, such emotions typically motivate the individual experiencing the emotion to avoid, rather than approach, the emotion‐eliciting stimuli (Lerner and Tiedens 2006). Fear, for example, leads individuals to avoid the fear‐inducing stimuli, removing one from dangerous or threatening circumstances (Cosmides and Tooby 2000). Anger, conversely, motivates approach, increasing individuals’ eagerness to act, inclination to take risks, and willingness to incur costs to oneself in pursuit of seeking redress from others (Lerner and Tiedens 2006). Second, anger is distinctive because of its unusually strong influence on cognition, including basic judgment and decision‐making processes. Anger does not “turn off” thought – rather, it seems to “hijack” thought, directing perceptual, motivational, attentional, and judgment processes away from typical operation, and toward the emotion‐eliciting stimuli; in other words, whatever makes you angry grabs and holds your attention (Lerner and Tiedens 2006).

Anger has numerous effects on behavior. For example, it can make people indiscriminately punitive, indiscriminately optimistic about their likely success, more self‐confident, and more likely to make snap decisions based on heuristics (decision‐making rules) rather than engaging in careful, effortful thought (Petty and Cacioppo 1986).

Anger can also increase dispositional attribution, leading angry individuals to perceive that others (rather than the situation or the self) are responsible for negative events (Quigley and Tedeschi 1996). Interestingly, anger also tends to intensify certainty about what happened (Lerner and Tiedens 2006). Additionally, research suggests that this may be a two‐way process: the person is more likely to feel anger when she is already overconfident about what happened and inclined to blame another person for it. For example, Jennifer Lerner and Larissa Tiedens (2006) suggest that when individuals are uncertain or lack confidence about the cause of negative events, their typical emotional reaction is fear or anxiety, not anger. Similarly, when individuals feel responsible or blameworthy for negative events, the typical emotional reaction is not anger but guilt or shame. When situational forces outside the control of the self or another individual are blamed for negative events, the typical emotional reaction is sadness (Lerner and Tiedens 2006). Thus, assignment of blame, and (over)confidence in such assignment, seems to be a key component of anger: these both catalyze anger and are catalyzed by it.

Evidence also suggests that men and women do not differ in either the frequency or intensity of experiencing anger (Fessler 2010), but they do seem to diverge in their likely responses: men are more likely to use direct aggression intended to inflict physical costs, whereas women are more likely to engage in indirect aggression intended to inflict reputational costs (Fessler 2010).

In sum, angry individuals tend to be overly confident, optimistic about their chance for success, inclined to blame others, and unlikely to engage in effortful thought – effects that sound like a cocktail for disaster in the mediation context. The evolved functions of anger, however, and the downstream cognitive and behavioral effects of being angry, have important implications for successfully managing anger in dispute resolution.

Conflict often occurs as a result of perceived transgression and also when people believe that the actions of others present obstacles in the way of achieving their own goals. Thus, if anger evolved to facilitate positive fitness outcomes in the face of obstacles and transgressions, it is no surprise that dispute resolution is a fertile ground for activating an anger response. Understanding the functions of anger and the environmental cues likely to elicit it, we argue, can provide mediators with useful tools for managing (or even leveraging) anger and keeping conversations productive. Here, we examine anger in the mediation context through the lens of evolved psychological processes (welfare trade‐off and transgression response).

Anger and Negotiation

Negotiation, an interactive process by which parties attempt to coordinate their behavior or allocate resources in a way that they believe will make them better off (Korobkin 2004), is widely recognized as an emotional activity (Adler, Rosen, and Silverstein 1998; Leary, Pillemer, and Wheeler 2013). Because mediation is broadly defined as the “process of assisting the negotiations of others” (Frenkel and Stark 2012: 2), an essential skill for mediators is managing negotiators’ emotions and their emotion‐laden communications in an attempt to keep bargaining efforts progressing (Sinaceur et al. 2013; Moore 2014).

Some social scientists have studied anger in negotiation contexts from a social‐functional approach, under the premise that emotions have two primary purposes: facilitating individual survival and group cohesion (Olekalns and Druckman 2014). Researchers using the “emotions as social information” model (EASI) have focused on the impact that expressions of anger have on other parties in negotiation settings (Adam and Brett 2015). The broad conclusion from this research is that expressions of anger elicit greater concessions from negotiation counterparts than do expressions of happiness or emotional neutrality (van Kleef, De Dreu, and Manstead 2004; Côté, Hideg, and van Kleef 2013), although several factors have been found to moderate this effect (e.g., the parties’ relative power, their cultural backgrounds, and so forth) (Adam and Brett 2015).

In one study, Hajo Adam and Jeanne Brett (2015) examined the effects of anger expression on concession‐making in negotiation. They found that targets of anger respond differently depending on whether the negotiation setting is more cooperative, more competitive, or balanced between the two. The researchers defined cooperative settings as those in which people “experience high levels of trust, benevolence, and the motivation to work together,” competitive settings as those in which people “experience high levels of distrust, selfish and defensive desires, and the motivation to engage in strategic behavior,” and balanced settings as containing “both cooperative and competitive elements that render the situation uncertain and ambiguous” (Adam and Brett 2015: 45).

In both cooperative and competitive settings, the researchers found that expressions of anger elicited hostile reactions in targets, such as decreased interpersonal liking, reciprocal anger, or the desire to retaliate, which resulted in fewer concessions. In balanced settings, however, expressions of anger led targets to make “strategic inferences,” predictions about the expresser’s toughness and intentions. Targets of anger then used this information to assess whether there was a real threat of impasse or escalation, requiring behavioral adjustments (Adam and Brett 2015). As a result, the expression of anger in balanced settings led targets of anger to make greater concessions.

To explain these findings, the researchers proposed that in cooperative settings anger displays are inappropriate signs of hostility that violate norms of positive and socially engaging emotions. As a result, targets of anger respond with “particularly powerful negative” hostile reactions (Adam and Brett 2015: 46). Similarly, in competitive settings, negotiators are already likely to be defensive and primed to react with hostility; anger “adds fuel to the fire and increases the likelihood of a retaliatory emotional response” while decreasing the likelihood of a measured response (Adam and Brett 2015: 46). In contrast, the inherent uncertainty and ambiguity of balanced situations requires negotiators to move past their emotional reactions and focus on diagnostic cues in order to determine exactly what information is being conveyed. Thus, balanced settings provide negotiators with the space necessary to even consider the intent and toughness of the person expressing anger.

Viewing the results of this study (Adam and Brett 2015) through an evolutionary lens, findings about anger in the cooperative situation suggest that anger itself may be perceived as a transgression. The researchers acknowledge that anger expressions in cooperative settings violate social norms calling for positive and agreeable behavior. If the initial anger is viewed as a norm violation, the anger target may then be driven by a “hostile reaction” to deter future transgressions by inflicting costs on the transgressor (e.g., withholding concessions). Similarly, in competitive settings, Adam and Brett (2015) acknowledge that negotiators are more likely to be defensive and quick to match anger with anger. If an angry negotiator violates certain negotiation norms, such as notions of fair dealing, those violations may be met with anger to deter future transgressions.

From a welfare‐tradeoff perspective, anger displayed in both cooperative and competitive settings may suggest insufficient weight placed on the welfare of the target, leading the target to use reciprocal anger as a welfare recalibration strategy. Adam and Brett’s (2015) findings suggest, however, that the targets of anger may themselves recalibrate when settings are balanced, making inferences about the formidability of the angry negotiator and their ability to inflict costs or withhold benefits. As predicted by the welfare trade‐off framework, Adam and Brett (2015) find that targets of anger are most likely to make concessions when the angry negotiator is perceived as dominant and tough, and poses the threat of an impasse.

Anger and Power

Power, broadly defined as the ability to make things happen or to bring about desired outcomes, is a fundamental variable in negotiation (Coleman 2000). Parties in negotiation rarely have equivalent power because power is a relational concept determined by the interaction of the characteristics of the person(s) involved and the characteristics of the situation (Coleman 2000). Because negotiation power is an abstract and ambiguous concept in negotiation, bargaining power is sometimes described as stemming from “the negotiator’s ability to, explicitly or implicitly, make a single threat credibly: ‘I will walk away from the negotiating table without agreeing to a deal if you do not give me what I demand’” (Korobkin 2004: 867). Because negotiators are left to calculate the credibility of this threat, it is the perception of power that matters most, rather than its mere presence (Adler and Silverstein 2000).

Social scientists have long been fascinated with power and its role in social interactions. For example, researchers have found that more powerful individuals are more expressive of anger, are less likely to take the perspective of others, are more likely to use others as means to an end, are more sensitive to rewards, and are more assertive in pursuit of those rewards (Overbeck, Neale, and Govan 2010). In the negotiation realm specifically, researchers have found that the combination of anger and power has both intrapersonal (internal) and interpersonal (external) impact on negotiators. On the intrapersonal front, high‐power negotiators are more likely to respond to their own anger by becoming more cognitively focused on the negotiation and making higher demands, resulting in an ability to claim more value (Sinaceur and Tiedens 2006). Low‐power negotiators, on the other hand, are more likely to respond less to their own emotional state than to that of their higher‐power counterpart (Overbeck, Neale, and Govan 2010). When confronted with anger from high‐power negotiators, whether such anger is justified or not, low‐power negotiators lose cognitive focus and make more concessions (van Kleef and Côté 2007; Overbeck, Neale, and Govan 2010).

Interpersonal impact is not just a driving force for low‐power negotiators. When confronted with angry low‐power negotiators, high‐power negotiators respond with higher demands when the anger is seen as unjustified (van Kleef and Côté 2007). When confronted with justified anger from low‐power negotiators, high‐power negotiators demand less from them than from negotiators expressing no emotion at all (van Kleef and Côté 2007). Thus, with some exceptions, expressions of anger can be somewhat risky for low‐power negotiators and tend to enhance negotiation outcomes for high‐power negotiators.

The studies discussed here did not investigate the psychological mechanisms behind the reported results, but they nonetheless appear to support both transgression theory and welfare trade‐off theory. If categorizing a low‐power negotiator’s anger as justified is synonymous with a high‐power negotiator’s recognition of having committed a transgression, offering better negotiation terms would be one method of making amends for the transgression. Moreover, high‐power negotiators likely perceive unjustified anger from low‐power negotiators as a transgression in itself; presumably the resulting unfavorable negotiation terms are harms inflicted for the purpose of reducing further transgressions.

From a welfare trade‐off framework, high‐power negotiators are better able to inflict costs or withhold benefits, thus motivating the low‐power negotiators to recalibrate the weight placed on the high‐power negotiators’ welfare. Furthermore, when low‐power negotiators express anger, high‐power negotiators may not perceive sufficient potential fitness benefits for recalibrating and thus are unlikely to increase the weight placed on low‐power negotiators’ welfare, increasing their own demands instead.

Mediators have long been advised to address emotional issues when they arise so that they do not thwart resolution (Lieberman 2012). Here, we discuss how understanding the evolutionary underpinnings of anger can be usefully put into practice by mediators, including the use of possible strategies for mitigating its potential negative effects going forward. We begin by briefly reviewing well‐established approaches to managing anger in mediation, and then highlight potential insights drawn from an evolutionary psychological perspective.

First, mediators must understand that emotions cannot be “resolved,” they can only be experienced, released, reconsidered, and understood (Moore 2014). Thus, mediators should accept and acknowledge a party’s anger, essentially giving permission for anger displays (Golann and Folberg 2011). This allows the anger to become a part of, maybe even the focus of, the conversation for a period of time, and lets the angry person know that his or her feelings matter. Most importantly from a conflict resolution perspective, the person expressing anger knows that the mediator is working to understand the entirety of the conflict and its presenting problems (Moore 2014).

Failing to address anger in mediation typically affects negotiation in three counterproductive ways (Moore 2014). First, it indicates that the mediator is not attentive to the entirety of the conflict, which is often described by the disputant as “not listening.” This results in decreased faith and trust in the mediator. Next, as described earlier, lingering anger negatively affects one’s ability to listen. Finally, the anger will likely reappear in subsequent conversations, typically in an unproductive way. Simply stated, acknowledgment is “a step that cannot be skipped” (Moore 2014: 106).

Simple acknowledgment is not enough, however. Mediators need to understand the expresser’s anger. Most people want others to understand why they are angry and to see merit in their concerns (Fisher and Shapiro 2005). Expressions of a true understanding of their experience humanize the mediator and allow her to develop trust with, concern for, and respect from the angry individual, all of which serve to defuse anger (Fisher and Shapiro 2005).

Here, an evolutionary approach may provide insight. Displaying understanding using the language of transgression deterrence or welfare trade‐off theory cultivates empathic understanding and creates trust in the mediator, a mediator’s most valuable asset. For example, when a party’s anger is transgression‐related a mediator can say things like: “She is still upset with the fact that her team knew you were in negotiations with potential replacements before she even knew her job was in jeopardy,” or “You’re angry with your colleague for taking credit for your work, that makes sense,” or “There’s no need to apologize for being angry, it’s a normal reaction when one feels victimized. I would be surprised if you weren’t angry.”

With regard to welfare trade‐off theory a mediator could say, “You’re saying that driving that fast in those conditions showed a complete lack of regard for the safety of others, not to mention the kids in the backseat. That would make a lot of people angry,” or “It makes sense to me that you’re angry when your business partner makes a major business decision without any regard for the impact it could have on your personal finances.” Furthermore, directing the conversation along those lines may make it easier to discuss the emotion going forward by creating temporal distance from the expression of the anger, giving the angry person time to regain composure – a crucial step in dissipating anger (Ladd 2005; Moore 2014).

Discussions around anger are also productive for other purposes. They can provide important talking points for subsequent meetings with both the angry person and his or her counterparts in the dispute. For example, the discussion may be the entrée in reorienting a party on what might be a reasonable expectation as opposed to focusing strictly on demands (Schein 2015). The information gleaned could also help the mediator anticipate strategic problems and opportunities that may present themselves later in the negotiation and facilitate distributive moves (Fisher and Shapiro 2005).

Again, familiarity with an evolutionary psychological framework offers helpful tools. For example, the mediator may be able to point out that steps to “correct” the perceived transgression could be overly costly. Also, when a mediator knows that the angry disputant is both less powerful and her or his anger seems unjustified, the mediator may help the disputant by explaining to the opposing party why the anger may be more justified than it appears.

As mediators well know, bargaining over money or distributive issues often generates anger. The parties may communicate indirectly by making financial proposals, and their messages are often unclear, reactive, and inaccurate (Little 2007). As a result, mediators spend a lot of time helping the parties overcome their angry and hostile reactions to offers and counteroffers in order to keep the mediation moving forward.

This is when good mediators act as negotiation coaches, advising parties on their negotiation strategy and tactics and how their proposed counteroffers may be received (Hoffman 2011). An evolutionary approach can be helpful here as well. For example, in response to a proposed offer that appears to be a clear violation of negotiation protocol, such as “going backwards” by making an offer that is less attractive than the party’s last offer, the mediator can discuss the potential anger response this move could generate, even if it is justified (Little 2007). Similarly, the mediator could address a hostile response to a low‐ball offer in a personal injury claim by making a nod to the angry disputant’s welfare, acknowledging that she believes that the offer fails to sufficiently consider her ongoing condition. When the mediator both understands and normalizes the anger response in these ways, a party is likely to pass through the anger more quickly; this is an important transition to undergo before proposing a productive counteroffer.

Understanding the evolutionary underpinnings of anger may also help mediators prepare for mediation. Mediators can anticipate where anger is likely to arise such as during discussions of real or perceived transgressions, whether these perceived transgressions are part of the substance of the conflict or actually occur during the mediation process. The same can be said for discussions surrounding welfare recalibration and reputation. Mediators may strategize their responses to anger (e.g., diving into the emotion, or simply listening, understanding, acknowledging, and empathizing) and recognize the need to be flexible in response to anger expressions (Golann and Folberg 2011). If anger fails to arise in those moments, mediators can direct the conversation to discover why. It may be that the emotion is being suppressed, or there may genuinely be no anger. No matter the circumstance, mediators must be prepared to listen to strong anger expressions without becoming flustered or unilaterally quelling them (Golann and Folberg 2011; Moore 2014). A better understanding of the functions of anger will aid mediators to predict and manage its expression.

Finally, experienced mediators know anger outbursts are different when disputants are together compared to when they are in caucus. From an evolutionary perspective, such face‐to‐face interactions have implications for heightened reputational concerns. The challenge for the mediator is assessing the party’s or parties’ anger in the context of the dispute and determining the circumstances in which expressing the anger and delivering the angry messages will be most productive (Schein 2015). If presented with a choice, most mediators would rather do their anger‐related work in caucus, where it is less likely to result in unproductive behavior that may cause barriers to resolution (Moore 2014). But mediators are not always presented with a choice. If anger arises when parties are together in a joint session, mediators are best advised to remain empathic, and to gauge whether the anger expression is productive or counterproductive. If a mediator cannot reorient the discussion to a more productive path, a caucus should be taken to address the emotion (Moore 2014).

We have chosen the emotion of anger to illustrate how evolutionary understandings of emotions can be useful in mediation because anger is rife in conflict resolution and has been well researched by both mediation scholars and evolutionary psychologists. We submit, however, that an evolutionary psychological perspective may be applied to any of the emotions exhibited in mediation, including anxiety, joy, fear, sadness, shame, and so forth, each of which have important implications for effective dispute resolution. To demonstrate the breadth of our approach, we briefly discuss our framework as applied to gratitude, an emotion that sharply differs from anger in experience, function, and “valence,” which refers to whether it is negative or positive.

Gratitude

Gratitude, like anger, is a cross‐culturally universal emotion (McCullough et al. 2001). Gratitude differs from other positive emotions, such as happiness, in that it requires a particular antecedent: the perception that one has benefited from another’s generosity (McCullough, Kimeldorf, and Cohen 2008). The extent to which we feel gratitude in response varies as a function of the perceived costs imposed on the benefactor, the value to the beneficiary, and the intentionality and voluntariness of the beneficial act (McCullough, Kimeldorf, and Cohen 2008). Because the experience of gratitude is inherently social (that is, it occurs as a result of the interaction between individuals), evolutionary psychologists suggest that the function of gratitude is also social in nature. Specifically, gratitude helps people form and sustain social relationships by motivating prosocial behavior (McCullough, Kimeldorf, and Cohen 2008). Thus, gratitude may have evolved to help convert acquaintanceships with genetically unrelated strangers into mutually beneficial reciprocal relationships (McCullough et al. 2001).

Studies provide some empirical support for this proposed process. For example, research finds that individuals who are thanked for their work are willing to give more, and work harder in the future, than people who are not thanked; in addition, simply writing “thank you” on a restaurant bill increases the amount of tip money that servers receive (McCullough, Kimeldorf, and Cohen 2008). Such expressions of gratitude signal that the beneficiary has noticed the kindness, and thus might be more likely to reciprocate in the future. This expectation of reciprocity is critical for effective social exchange, as cooperation with nonreciprocators (e.g., cheaters, free‐riders) can be extremely costly (Fehr, Fischbacher, and Gächter 2002). Gratitude, therefore, may help signal that an exchange partner is likely to reciprocate, resulting in increased trust and cooperation on the part of the benefactor.

Some evolutionary psychological theorists suggest that gratitude may motivate not only reciprocity, but also a concern for the well‐being of third parties (Nowak and Roch 2007). This phenomenon, known as “upstream reciprocity,” refers to behavior in which the beneficiary “pays it forward,” passing benefits onto third parties rather than returning benefits directly to the benefactor. Empirical research offers some support for the upstream reciprocity hypothesis, finding that gratitude increases people’s willingness to help third parties (Bartlett and DeSteno 2006). In sum, scholars believe that gratitude functions to create and sustain positive relationships, particularly with individuals from whom we are genetically and socially distant. Additionally, gratitude helps us to consider the value and benefit of our interdependent social relationships.

Gratitude’s evolved role in facilitating cooperation and prosociality suggests multiple, potentially fruitful applications for mediators seeking to assist parties to reach resolution. First, mediators can model gratitude by expressing thanks when appropriate (e.g., thanking the parties for being forthcoming or making concessions throughout the mediation process) in the hopes that their gratitude will inspire upstream reciprocity. In addition to feeling reciprocal gratitude toward the mediator, the disputant may also display an increased prosocial behavior toward the opposing party. The parties may also feel more motivated to help the mediator succeed, which can in turn benefit the opposing party in the form of concessions or improved offers. Thus, sincere efforts on the part of the mediator to show gratitude toward the parties may actually put the parties in a more cooperative frame of mind toward one another.

Second, mediators may be able to promote gratitude between the parties by encouraging disputants to proffer true and full apologies, particularly in cases in which the recipient seeks out or highly values a sincere, intentional, and voluntary apology. Apologies that the parties perceive to be insincere and forced, however, are unlikely to elicit gratitude and may be counterproductive to achieving resolution (Frenkel and Stark 2012). To ensure that apologies are effectively communicated, mediators can assist parties to craft the content of the apology and identify opportunities when apologies might have the most impact.

Third, because of gratitude’s evolved function to support reciprocal relationships, mediators can highlight positive past behaviors to leverage gratitude, especially when the parties’ relationship is long‐standing and has potential to continue, albeit with different parameters. For example, a dispute between neighbors, employees, divorcing spouses, or members of a family business may offer mediators the opportunity to leverage gratitude by emphasizing moments when the parties appreciated and were thankful for each other’s efforts. Once the parties acknowledge their past gratitude, they may slowly increase their willingness to behave more generously toward one another to reach a settlement. In some cases, the parties might actually begin discussing the possibility of a future and continuing relationship, especially in family matters involving children. In such cases, mediators can introduce potential opportunities for reciprocal benefits in the future.

Gratitude’s effects on behavior illustrate the ways in which reciprocity can be a force for achieving resolution. As individuals, we feel compelled to return benefits that are conferred upon us, and this may be especially true when we recognize that the benefactor has incurred a cost for his or her generosity. By moving parties away from the notion that opposing parties are “obligated” to accept blame, pay up, and reach an agreement, mediators can help parties view one another’s concessions as costly to the conceder and valuable to the recipient. Gratitude may inspire gratitude in turn, resulting in reciprocal cooperation and facilitating eventual resolution.

Mediators will inevitably face emotional outbursts in the course of dispute resolution. Emotions are fundamental to the conflict experience, and can both impede and promote settlement. Emotions influence not just what we think, but how we think – our attention, perception, and memory, as well as our physiological state and mood, and our goals and behaviors – often in ways intended to produce functional outcomes. In this article, we described the evolutionary psychological approach to emotions and explored how it can be applied in the mediation context, highlighting the complexity of emotions, and the implications for understanding, predicting, and managing emotions in mediation.

We also seek here to provide a coherent theoretical framework from which to consider existing research and generate new hypotheses about human behavior. We propose that applying an evolutionary psychological lens to understanding emotions is likely to be a fruitful and informative area for future mediation scholarship. Contrary to B. F. Skinner’s assertion that emotions are useless, mediators have much to gain from considering the adaptive functions of emotions and, ultimately, their effects on human behavior.

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