Feature Article: Evolution and Integral Leadership: How the Homo Got Its Sapiens

Roger Stace


Roger StaceWhile much is known about how biological evolution has shaped human physical traits, less is known about why human mental traits evolved. It remains an ongoing puzzle how humans could have evolved the traits that integral leaders exhibit, such as interpersonal warmth, compassion and wisdom. This paper reviews existing theories for why these human capacities evolved, and then proposes a new theory for why these beautiful and inspiring aspects of human nature are adaptive. Specifically, transcendence has been sexy for hundreds of thousands of years. Implications for Integral Leadership are then discussed.


For many years I have been fascinated by both evolutionary psychology and integral theory. Reconciling these two interests has been difficult, since the result is an atheistic view of human virtues and spirituality. Ever since Sir Charles Darwin introduced the idea of evolution, many have found it offensive, since it plausibly explains the nastier aspects of human nature, without clearly explaining the higher and more beautiful aspects of human nature. This paper, based on part of my doctoral dissertation, proposes that the capacities displayed by integral leaders are natural, evolved, and rational. Homo sapiens translates as wise hominid, and this paper proposes how our species evolved an ability to display wisdom.

In his influential book The Selfish Gene (1978), Richard Dawkins described how evolution requires that genes are selfish. This requirement has often been interpreted as meaning that people, like their genes, must be fundamentally selfish. The idea that humans are innately selfish is therefore biologically plausible, and has become a basic axiom of microeconomics and game theory (Schwartz, 1986b). Within academia a number of researchers have theorized about why people are not always totally selfish. These theories tend to be called theories of human cooperation or altruism, rather than theories of human virtuousness. These existing theories can explain some, but not all forms of human virtue.

Existing Theories of Why Humans Aren’t Always Selfish

The four theories that currently exist to explain the evolution of human cooperativeness are group selection (Wilson & Sober, 1994), kin selection (Hamilton, 1963), reciprocal altruism (Trivers, 1971), and costly signaling (Zahavi, 1975). These theories each have limitations. For example group selection requires individual selection to be relatively weak, which many biologists doubt (Dawkins, 1994), while kin selection can’t explain generosity between individuals who are not related.

Direct reciprocal altruism was initially described by Trivers (1971) as an evolved psychological willingness for people to be generous when they have excess resources (such as food), because such generosity is likely to repaid in the future (such as when the giver is hungry). Axelrod and Hamilton (1981) formalised this insight that the expectation of future interactions (or more dramatically, “the shadow of the future”) forces altruism to be repaid. If future interactions are unlikely, then the altruism is unlikely to be repaid, so altruism should not occur. Henrich et al. (2005) however found strong evidence that people around the world are typically generous even when future interaction is impossible. Recent mathematical models of direct reciprocal altruism have also shown that cooperation should be restricted to small cliques within a group, rather than to all members of a group (Hruschka & Henrich, 2006). For these reasons, there are difficulties in relying on direct reciprocal altruism to explain widespread generosity by humans.

Another version of reciprocal altruism is indirect reciprocal altruism (Fehr & Fischbacher, 2003; Nowak & Sigmund, 1998) in which individuals are altruistic in order to earn a good reputation, and observers who are not direct recipients of the altruism will subsequently reciprocate the observed generosity when needed. The difficulty with this theory is a lack of enforcement mechanism (Zahavi, 2003). A person’s generosity will hopefully be reciprocated by some impressed observer, but even a genuinely impressed observer doesn’t need to return a favor they didn’t receive (Panchanathan & Boyd, 2004).

In biology, costly signaling is a widely accepted model for understanding animal communication. A trait or behavior that is costly to an individual can also make that individual more sexually attractive. This strange effect occurs because only a costly signal can honestly advertise the true quality of an individual. The most famous example of this advertising is the peacock’s tail. Only those peacocks with good genes and health can afford the burden of possessing and displaying a large, bright, symmetric tail. Weaker peacocks can not afford to advertise as much. Therefore peahens wishing to select the peacock with the best genes and health are attracted to the peacock with the largest, brightest, most symmetric tail. A mathematical model has shown that costly signaling is generally applicable for ensuring reliability in communication between competing organisms (Grafen, 1990aa; 1990bb). Gintis et al. (2001) similarly demonstrated that cooperation by individuals within a group could have evolved as a sexual advertisement..

For a signal to be informative, it must allow an individual to distinguish themselves as somehow ‘better’ than a lower-quality competitor. For example, the fact that I can walk around a room is an informative signal that I’m better at walking than a newborn infant: I can do it, and a newborn can’t. The same signal is not informative if I’m trying to show that I’m better than someone else who can walk. The signal is too easy since both of us can successfully display the signal. If a signal is so hard so that no one can display it, it is also useless. Other mathematical models of costly signaling (Bergstrom & Lachmann, 1998; Bergstrom, Szamado, & Lachmann, 2002; Lachmann, Szamado, & Bergstrom, 2001) have shown that a signal can be informative even if it’s only costly (or otherwise difficult) for low-quality types of signaler.

As Henrich et al. (2005) point out, there are many types of costly signal that individual humans use that enhance their reputations- including turtle hunting (Smith & Bleige Bird, 2000) , kerosene drinking (Diamond, 1991; In addition to kerosene drinking by Indonesian kung fu enthusiasts, Diamond (1991) describes other eye-poppingly costly signals of vitality such as bungee jumping using jungle vines by men in Vanuatu; ancient Mayan hallucinogenic enemas; and tattoos. Diamond also speculates that tobacco and whisky advertisements function by implying these products signal an individual’s social desirability and vitality.), and mountain climbing (Loewenstein, 1999). Costly signaling theory therefore could explain the evolution of altruistic cooperation, but does not explain the diversity of signals used by humans. The remainder of this paper describes a refinement of costly signaling theory that plausibly explains why people willingly behave in a wide variety of ways that advertise their virtue. Displaying competence as an integral leader is innately pleasurable because even though it is difficult, it is reproductively valuable for our genes.

An Outline of Emergent Costly Signals Theory

Of his theory of sexual selection by mate choice, Charles Darwin wrote that both extravagant physical traits and impressive mental traits seem to have arisen by sexual selection, which in turn depends on the psychology of the observer:

“He who admits the principle of sexual selection will be led to the remarkable conclusion that the cerebral system not only regulates most of the existing functions of the body, but has indirectly influenced the progressive development of various body structures and of certain mental qualities. Courage, pugnacity, perseverance, strength and size of body, weapons of all kinds, musical organs, both vocal and instrumental, bright colours, stripes, and marks, and ornamental appendages, have all been indirectly gained by the one sex or the other, through the influence of love and jealousy, through the appreciation of the beautiful in sound, colour or form, and through the exertion of choice; and these powers of the mind manifestly depend on the development of the cerebral system” (Darwin 1871, vol 2, p 402).

Darwin’s theory of sexual selection recognized that typically, females shape the evolution of a species by choosing males. From this perspective ‘survival of the fittest’ is less important than ‘reproduction of the sexiest’. Perhaps because of its political incorrectness, academic theorizing based on sexual selection has been uncommon until recently (Miller, 2000). Emergent costly signals theory is a theoretical model based on sexual selection both by males and females, and is proposed in this paper as a potential explanation for human values and virtues.

The mathematical details of emergent costly signals theory are described elsewhere (Stace, 2008), but the intuition is as follows: Imagine there is one best sexual advertising strategy used by all members of a species (this is known as an evolutionarily stable strategy). Each successive generation will on average be better than its parent generation at displaying the advertising strategy (since only the best advertisers pass on their genes). This results in a ‘red queen’ process, which is named after the queen in Alice’s Wonderland who had to run as fast as she could just to keep up with everyone else (Ridley, 1993). The red queen effect means that after many generations, an individual can’t just be very good at the advertising strategy (since everyone else will also be very good), they must be extremely good to be seen as sexually attractive. Sooner or later the advertising strategy will become so absurdly exaggerated that a practical constraint will be reached. No matter what the constraint is, when a large number of advertisers reach the constraint, the advertising strategy will become less effective for telling quality apart, and a supplementary strategy is needed. For example in a classroom, if all students become able to get 100% in a test, the test becomes useless for identifying who the best students are. To identify who the best students are, a more difficult test would need to be given.

Ego Development Stages as Sexual Advertising Strategies

We can now speculate on how emergent costly signals theory might apply to human levels of consciousness. Stages of ego development may exist in humans because they are a sequence of emergent sexual advertising strategies. The evidence that humans are innately capable of using these particular strategies comes from features common to a large number of ‘stage’ theories in developmental psychology (Wilber 2000). In ancient humans, whatever strategy was best for surviving and reproducing spread throughout the population. Whenever medium quality individuals became able to imitate high quality individuals, a supplementary advertising strategy became adaptive for high quality individuals to distinguish themselves.

Ego development theory (Cohn & Westenberg, 2004; Loevinger, 1976, 1983; Loevinger & Knoll, 1983; Manners & Durkin, 2001) provides a detailed sequence of cognitive strategies that people progressively utilize as they mature. Loevinger and colleagues documented that young children are ruled by impulses (impulsive stage), but soon learn to restrain their impulses by anticipating reward and punishment (self-protective opportunist stage). Rules are only followed to avoid getting in trouble. However, older children usually learn to appreciate rules and norms, and to internalize their value, because following the rules signifies membership within a group (conformist diplomat stage). At widely varying ages, a majority of people begin to appreciate that even within their group there is value in being distinctive, by developing and showing off expertise (self-conscious expert stage). A large number of adults develop beyond just wanting to be an expert, and learn to appreciate that getting results is more important than being seen to be right. They willingly admit mistakes in order to achieve goals (conscientious achiever stage). This conscientious achiever stage is self-driven and enjoys meaningful work- usually for the benefit of an organization. Some adults progress into a more complex stage of cherishing diverse perspectives, and the uniqueness of every individual (individualistic pluralist stage). People at this stage are painfully aware that some perspectives oppress other (equally valid) perspectives, and so are highly egalitarian, and endorse post-modernist or feminist ideals. A small number of adults develop to a further stage of being able to reconcile diverse perspectives- honoring both compassion and pragmatic action (autonomous strategist stage). Loevinger found some evidence of further stages, but due to the rarity of people to study, only characterized other stages tentatively. Subsequent work by Cook-Greuter (2000) focused on these higher stages of ego development. The sequence of ego development stages examined in the present chapter is: impulsive, self-protective opportunist, conformist, expert, achiever, pluralist, and integral.


Ego development theory describes young children as ruled by their impulses. Although any speculation on the psychology of proto-humans will necessarily be at best incomplete, it may be useful to use the approximation of selfishness as a starting point. Imagine a population in which each individual acts only in response to selfish impulses. They eat when hungry, drink when thirsty, and fight if a competitor gets in the way. In particular, competing individuals fight over resources and sexual access. “Nature, red in tooth and claw”, and life as “nasty, brutish and short” may be apt descriptions of any population limited to such a strategy ( From the poem In Memorian (1850) by Lord Alfred Tennyson, and Leviathan (1651) by Thomas Hobbes respectively). Survival would depend on well-designed survival impulses, and reproduction would depend on displaying such traits as apparent vitality, fertility, and fighting prowess. Sexual selection of males by females would presumably use some form of “He-man” criterion (Dawkins & Krebs, 1979), in which size, strength and fighting prowess are important. If “He-man” displays were an ESS, fighting prowess, physical impressiveness, and ruthlessness would have been selected for. These traits would therefore increase over time due to the red queen effect (Dawkins & Krebs 1979).

Signals of impulsive (even murderous) vitality still have an adaptive role in humans. For instance, Chagnon (1968) notes that in Yanomamo society men who had killed other men had more wives and children than non-killers. In some environments, young men are particularly prone to competitive violence (Daly & Wilson, 1985), and in many societies the ratio of male/female deaths increases dramatically (Kruger & Nesse, 2004) when testosterone increases in males, indicating that testosterone encourages impulsive, competitive, sometimes violent displays of vitality (Mazur & Booth, 1998). Testosterone does not necessitate violence, but does seem a plausible physiological mediator of the impulsive “He-Man” advertising strategy. Incidentally, women find facial masculinity (an effect of testosterone), and direct intrasexual competitiveness most attractive when both fertile and considering a short-term mating strategy (Gangestad, Simpson, Cousins, Garver-Apgar, & Niels christensen, 2004).

Self-Protective Opportunist

As noted by Lorenz (1966), in many species males competing for dominance do not physically injure each other. Injury is usually avoided because the weaker competitor self protectively backs down and defers to the likely winner. This behavior reveals a strategy that is a refinement of a “fight to the death” strategy. Instead, each male displays deference to stronger males, and displays a form of pity toward weaker males who defer- by not killing them. Using a “fight no matter what” impulsive strategy becomes fitness-decreasing when opponents are likely to have deadly fighting competence. Displaying deference to stronger opponents therefore becomes a better strategy than impulsiveness.

Showing deference is opportunistic, in that it disappears as soon as a strong opponent is weakened. A display of deference can be used to placate others, while continuing to behave opportunistically. A human at the self-protective opportunist level is “preoccupied with control and advantage in his (sic) relations with other people” (Loevinger 1976, p. 17). Displays of toughness, superior vitality or domination are delighted in by people at this stage. Loevinger also notes that “For such a person, life is a zero-sum game; what one person gains, someone else must lose.

A red queen race based on opportunistic deference would cause everyone to become good at cheating, as well as detecting cheats. Eventually this would result in a stalemate of nobody being trustworthy, and nobody being trusted. A population of paranoid, sneaky, and lonely individuals may plausibly have resulted.


At the conformist diplomat level, the moral code of an individual “defines actions as right or wrong according to compliance with rules rather than consequences…(individuals) do not distinguish obligatory rules from norms of conduct, as we see when they condemn unusual dress or hair styles as immoral…” (Loevinger 1976, p. 18). Displays of loyalty, obedience, conformity with norms, and moralistic enforcing of norms are enjoyable for a person at this level. This strategy of avidly seeking membership of a group could well have emerged as optimal in a population of sneaky-but-lonely ancestral humans, but eventually when nearly everyone learned how to conform enough to win membership of a desirable group, then some other strategy would become necessary.

Self Conscious Expert

At the self conscious expert stage, people are only too willing to prove their expertise, their prowess, and the many, many ways in which they are almost always right. The phenomena of the ‘self-appointed expert’ or the insecure ‘know-it-all’ are examples of people signaling at this level. In a population of obedient-but-unimaginative conformists, this strategy of displaying expertise to one’s group could feasibly have been optimal. Individuals not only gain admittance to a group (by being obedient), they gain status within the group (by displaying expertise useful to the group).

Conscientious Achiever

The conscientious achiever not only “aspires to achievement”, but also “is likely to feel guilty if what he does hurts another person, even though it may conform to the rules” (Loevinger 1976, p. 21). In a population of experts all trying to impress their group members, the strategy of walking the talk and conscientiously getting results would be an effective refinement, and better advertising strategy than just being a know-it-all.


People at the individualistic pluralist stage of ego development value diverse perspectives, and are upset by the oppression of anyone. They are “consciously preoccupied with social problems” (Loevinger 1976, p.24). In a population of self-important experts, an achiever strategy is clearly superior for attaining an exalted social position. In a population of achievers however, proving one’s worth by achieving results that benefit the group requires ever-greater achievements. A positional arms race of achievement may lead to increasingly admirable achievements, but may also instigate an escalation of accomplishments that deplete natural resources and are ultimately harmful for a group (Diamond, 2005).

With many individuals competing to display their quality by achieving results, it becomes tempting to achieve results by exploiting others rather than by constructing “win-win” solutions. Other parties who are treated unfairly will quickly complain at the lack of distributive justice. Only individuals who are particularly skilled at the achiever strategy will be able to achieve results without exploiting others and incurring their vengeful wrath.

One way to distinguish oneself from competitors who are also using an achiever strategy, is to competitively derogate their achievements as being ultimately harmful to the group or exploitive in some way. This behavior epitomizes the pluralist strategy (Loevinger, 1976). The pluralist strategy doesn’t deny the achievements of others, but rather interprets them in a negative light. Individuals using the conscientious achiever strategy are accused (from either their victims or from pluralists) of being cruel, greedy, vicious, exploitive, small-minded tyrants. In order for individuals to avoid getting labeled with this sort of bad reputation requires a refinement of the achiever strategy, in which multiple perspectives are carefully considered.

A red queen race using the pluralist strategy however leads to an increasing number of perspectives being allowed for. While one highly achieving pluralist may incorporate three perspectives, another may allow for four. Such an arms race will quickly lead to “perspectival madness”, or being paralyzed by too many partially-competing perspectives. As a result, the pluralist strategy can encourage ‘idiot compassion’- trying to respect all perspectives, even dangerous or self-defeating ones. Appreciating the importance and contribution of all perspectives is a hallmark of post-modernism. The destructive effect of not prioritizing between a potentially infinite number of perspectives has been criticized by Wilber (2002) in the phrase “mean green meme”.


People at the integral, or autonomous strategist stage are “able to unite and integrate ideas that appear as incompatible alternatives to those at lower stages” (Loevinger 1976, p.24). They find it fulfilling to use skilful means to transform and resolve what others see as intractable conflict. This refinement of the pluralist strategy involves generously acknowledging the partial truths of multiple and apparently competing perspectives. Rather than competitively dismissing each perspective as “just one point of view”, for individuals skilled at seeing multiple perspectives, integrating perspectives to enable ‘win-win-win’ outcomes becomes an achievable challenge. ‘Win-win-win’, or integrative outcomes means facilitating solutions that are acceptable to competing parties, and also benefit the ‘common good’, of worldcentric ideals such as society and the natural environment. Attaining such win-win-win outcomes represents a display of wisdom (Sternberg, 1998).

For instance, “…an individual is wise to the extent he or she uses successful intelligence as moderated by values to (a) seek to reach a common good, (b) by balancing intrapersonal (one’s own), interpersonal (others’) and extrapersonal (organizational/ institutional/ spiritual) interests, (c) over the short and long term, to (d) adapt to, shape, and select environments” (Sternberg & Vroom, 2002) (p. 306). Displaying wisdom therefore requires compassionately integrating the partially-overlapping needs of parties within a given situation.

It is possible that displays of compassionate, sage-like wisdom have been a selected-for trait in humans since before the advent of agriculture. Anthropological accounts of small-scale societies refer to individuals who are venerated for their wisdom that transcends parochial interests. For example a man who has sufficient charisma to negotiate trade, marriages and military coalitions across multiple clans has a socially useful role, sometimes known as a “big man” (Johnson & Earle, 2000). Individuals fulfilling such a role not only facilitate regional economies, they also have social prestige, and multiple wives. Through being able to take multiple perspectives to resolve intergroup conflicts and win communal approval through charisma rather than aggressive dominance, a successful ‘big man’ displays generosity and wisdom that transcends ethnocentric fault-lines and selfish interests.

Over the course of human history many people have enjoyed high social status and reproductive success without being compassionate and wise. This observation is inconsistent with the theory developed in this paper. One explanation for the apparent inconsistency is that behaving as a petty tyrant or impulsive celebrity in a hunter-gatherer society (which is the environment our species evolved in) would not have worked. Rather, sage-like statesmen since before King Solomon have on average sired many children. For women it is feasible that for thousands of generations the role of wise woman, held in reverence across a network of communities has facilitated the genetic success of her children and grandchildren. The adaptive value of displaying compassionate wisdom is not a common topic for theoretical speculation, but it is perhaps a beautiful thought.

The Latin name of our species is Homo sapiens: the wise hominid. Emergent costly signals theory suggests the strategy that most effectively advertises an individual’s high reproductive value is to demonstrate appreciative, compassionate wisdom. Using this strategy requires the ability to sympathize with and use all earlier strategies, but also a willingness to forego relying on these earlier strategies. From this perspective, displaying wisdom transcends and includes the impulsive, opportunist, conformist, expert, achiever, and pluralist strategies.

Implications for Integral Leadership

An integral leader is a person who has attained competence at all of the advertising strategies described above, but most of all is capable of sustaining the intrinsic cost of displaying compassionate wisdom (i.e. the ‘strategist’ advertising strategy). They develop competence at empathizing with numerous perspectives and noticing their truths and limitations, without being ‘emotionally hijacked’ (Goleman, 2003) into using the competitive derogation characteristic of earlier strategies. Instead, they un-self consciously acknowledge the (partial) validity of even hostile viewpoints as an intellectually and emotionally honest “witness”. This integrity is a prerequisite to being an effective integral leader. The relative rarity of managers and policy-makers utilizing this strategy points to its difficulty (Bazerman, Baron, & Shonk, 2001; Cameron & Lavine, 2006; Kofman, 2006).

The effectiveness of leaders being able to display warmth, wisdom and compassion despite temptations to resort to earlier innate advertising strategies can be seen in the construct of transformational leadership. Transformational leadership was first described as ‘transforming leadership’, in which a leader seems to transform the motives of their followers from lower-order needs on Maslow’s hierarchy of needs to higher-order needs (Burns, 1978). Subsequent research has tended not to refer to Maslow, and has been criticized for lacking clarity on the underlying process of how transformational leaders influence subordinates (Yukl, 1999).

Emergent costly signals theory is consistent with the observed effects of transformational leadership. Transformational leaders are those who consistently use later signaling strategies rather than earlier strategies. They are able to avoid temptations to engage in competitive derogation (a feature of earlier strategies), and emphasize world-centric goals and aspirations rather than selfish aspirations. In doing so, transformational leaders are facilitating subordinates to themselves use later signaling strategies. Transformational leaders go beyond self-interest for the good of the group, help others develop their strengths, and articulate a compelling vision. Through these behaviors leaders can increase the salience of inclusive ‘possible selves’ (Lord & Brown, 2004), and credibly invite “internalization”, whereby a follower’s primary self-identity becomes service to the organization’s cause (Shamir, House, & Arthur, 1993). In this way, the phenomenon of transformational leadership is consistent with emergent costly signals theory.

Table 1 summarizes how different innate advertising strategies display distinct virtues and leadership behaviors. The fact that these displays are attractive does not mean that leaders are consciously showing off to appear sexy. Rather, displaying virtue using these strategies feels innately rewarding for the leader. Our human genes have programmed us to enjoy enacting a spectrum of human qualities.

table 1
Table 1: Costly signaling strategies, virtues displayed and leadership behaviors

Table 1 suggests that integral leaders are visionary, compassionate, and attentive to performance as well as conflict. These leadership behaviors are possible because the earlier innate advertising strategies (which capture the attention of many leaders) are perceived by integral leaders as relatively easy. They have little need to dominate, deceive, or prove others wrong. The bigger challenge is instead to create inspiring “win-win-win” solutions that honor people, organizations, and the environment in a manner that is workable (short term) and sustainable (long term). Because of their willingness to treat conflict as a challenging puzzle rather than as necessarily a cause of stress and anger, integral leaders are likely to manage poor performance and conflict in an attentive and useful way.

For humans to display Integral Leadership is not easy, even though it results from a natural, evolutionary process. Integral Leadership is therefore not artificial or a fad, but an innate expression of human potential. While existing theories of evolution have little relevance to Integral Leadership, emergent costly signals theory may be highly relevant. Integral Leadership is currently a weakly developed paradigm, at least in part because it lacks a plausible and internally consistent theory that parsimoniously fits with what is known, and allows testable predictions of what is not yet known. While emergent costly signals theory is a tentative, as-yet untested theory, it may allow future research in Integral Leadership to gel into a coherent paradigm. More confidence could also be placed in the theory proposed here if it was found to be consistent with a wide variety of research findings outside of leadership.


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