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Summary of:
Buss, D. M. (2007). Evolutionary Psychology: The New Science of the Mind. (3rd Ed.).
Boston: Allyn and Bacon.
And
Dawkins, R. (1989). The Selfish Gene. (2nd Ed.). New York: Oxford University Press.
Summaries by Megan St. Clair and Stacey Hewitt
For Dr. Mills’ Psyc 452 class, Spring, 2009
Evolutionary Psychology: The New Science of the Mind
Chapter 12 Summary
Summary By Megan St. Clair
STATUS, PRESTIGE, AND SOCIAL DOMINANCE
Why would people falsify their credentials and risk exposure as frauds in order to
enhance their status and social position? The answer is simple, social position is everything.
Status, prestige, esteem, honor, respect, and rank are accorded differentially to individuals in all
known groups. Therefore, people devote tremendous effort to avoid disrepute, dishonor, shame,
humiliation, disgrace and loss of face—because all of these things could result in lower status in
the social hierarchy. Studies show that status and dominance within these hierarchies form
quickly, sometimes taking only one to five minutes (Fisek & Ofshe, 1970). This suggests that a
strong universal human motive is status striving.
THE EMERGENCE OF DOMINANCE HIERARCHIES
Dominance hierarchies are even evident in the behavior of crickets and hens. A cricket
that tends to win a lot of fights will become more aggressive and will thus continue to win fights.
While a cricket that tends to loose fights will become more submissive and will thus continue to
loose fights. This shows the ability of crickets to assess their own fighting ability relative to
others and behave accordingly. Overtime, a dominance hierarchy emerged, whereby each cricket
could be assigned a rank order, with crickets lower in the hierarchy giving in to those higher up.
Hens establish a “pecking order” where they fight frequently until each hen learns that
she is either dominant or subordinate. However, both roles have advantages because both would
be better off if each could determine who would win in advance and simply declare a winner
without suffering the costs of fighting.
Therefore, selection will favor the evolution of these assessment abilities—psychological
mechanisms that include assessment of one’s own fighting abilities relative to those of others.
For humans, assessment mechanisms include the ability to enlist powerful friends, allies and kin.
The primary function of each is to avoid costly confrontations when outcomes of conflict can be
determined in advance. Dominant and submissive strategies both have functions for the
individual, and in the aggregate, the produce a dominance hierarchy. Dominance Hierarchy
refers to the fact that some individuals with a group reliably gain greater access than others to
key resources that contribute to survival and reproduction.
DOMINANCE AND STATUS IN NONHUMAN ANIMALS
Dominance and status striving is also evident in the behaviors of crayfish and
chimpanzees. Research has revealed that crayfish undergo changes in their nervous system as a
result of winning or losing dominance. In a dominant crayfish, serotonin makes the neuron more
likely to fire. In the subordinate, serotonin inhibits the neuron from firing. It is important to
remember; however, that one battle doesn’t determine permanent social status. This means that a
subordinate crayfish can become dominant if the circumstances change.
Chimpanzees also battle for dominance. In order to become dominant, male chimps make
themselves look larger and heavier, which will cause them to receive submissive greetings from
subordinate chimps. The achieved dominance status of male chimps comes with the perk of
increased sexual access to females who are most likely to conceive.
These behaviors have theoretical implications. First, hierarchies are not static. Depending
on the situation, a subordinate can become dominant and visa versa. Second, rising in primate
hierarchies depends heavily on social skills, notably the ability to enlist allies who will support
them in contests with other individuals. Increased sexual oppurtunities with females provide a
powerful adaptive rationale for the evolution of dominance-striving mechanisms. It also suggests
an evolutionary basis for the sex difference in the dominance-striving motive.
EVOLUTIONARY THEORIES OF DOMINANCE, PRESTIGE, AND STATUS
No complete theories of human status hierarchies have been proposed that do all of the
following:
- Specify the adaptive problems that are solved by ascending status hierarchies, as well as
explain why individuals accept subordinate positions within hierarchies
- Predict which tactics people will use to negotiate hierarchies
- Why status-striving is more prevalent among males than females
- Account for the behavior consigned to subordinate status
- Explain why people often strive for equality among members of the group
- Differentiate between dominance hierarchies (allocation of resources) and production
hierarchies (coordination and division of labor for achieving group goals)
- Should identify the different routes or paths to elevated rank or status, with dominance
and prestige as the important ones.
An Evolutionary Theory of Sex Differences in Status Striving
Males and females differ dramatically in their reproductive outputs. Male reproductive
success is typically much more unpredictable than female reproductive success. While they may
have an abundance of sperm and minimal investment in offspring, they still have to compete for
the available women to impregnate. On the other hand, all fertile females will succeed in
reproducing, regardless of their social status. Therefore, males need elevated dominance and
status, in order to increase their sexual access to women. This can be accomplished along two
paths: (1) Dominant men might have preferential selection by women as a mate, merely because
of their higher-status and accompanying ability to offer more (2) Dominant men might simply
take or poach the mates of the subordinate men, leaving these low ranking men helpless to
retaliate (intersexual domination).
Status and Sexual Opportunity
Is there evidence that elevated status in men actually leads to more sexual opportunities
with women? One research study assembled research data from the first six civilizations that
showed that kings, emperors, and despots routinely collected women in harems, choosing the
young, fertile, and attractive. Even more recent genetic analyses have confirmed the effects of
status, power, and position on reproductive outcomes of these kings, emperors, and despots
whose genetic results can be linked to an abundance of offspring. This linkage appears to hold in
modern times as well, despite the changes in time and the movement toward monogamy. Men
greater in social status gain greater access to a larger number of women, (even if married)
through short-term sex partners or extramarital affairs. High-status males also have more
frequent sex and a larger number of children. Furthermore, high-status men are able to marry
females who are considerably more physically attractive, as well as women who are younger and
more fertile. Thus, despite modern day changes in sexual affiliation, the link between a man’s
status and sexual access to young, attractive women has remained the same. This suggests a sex
difference in the strength of the motivation to achieve high status, whereby men are considered
to have a more powerful selective rationale for a status-striving motive because it increases
sexual access to women.
Are Men Higher in Status Striving?
Research findings support the evolutionary theory that there is a sex difference in
motivation to gain dominance or status. Studies have shown that young boys immediately issue
dominance challenges to their peers, whereas, girls tend to display nurturance and pleasing
sociability. Furthermore, research on social dominance orientation (SDO) revealed that those
who were high on this orientation should be higher in men than in women because such an
orientation led ancestral men to greater control of, and access to women. In addition, women
would have been selected to choose men high in SDO, since this would offer them and their
children more benefits. Also, men consistently score higher than women on SDO scales. In sum,
men appear to score higher on attitudes endorsing getting ahead, including those that justify one
person’s status than another and one group’s dominance over another.
Men and Women Express Their Dominance Through Different Actions
Another source of evidence for a sex difference in dominance comes from the acts
through which men and women express their dominance. One study listed 100 acts mentioned as
dominant. Profound sex differences emerged. Women more then men tended to rate prosocial
dominant acts as more socially desirable, while men tended to rate more egoistic dominant acts
as more socially desirable. In other words, men tend to perform acts in which others are
influenced for the direct personal benefit of the dominant individuals. While, women appear to
express their dominance primarily through actions that facilitate group-functioning and wellbeing.
Another researcher, Megargee, examined the effect of dominance on leadership among
four groups: (1) high dominant man with low dominant man, (2) high dominant woman with low
dominant woman, (3) a high dominant man with a low dominant woman, and (4) a high
dominant woman with a low-dominant man. Megargee wanted to find who would become the
leader and who would become the follower. He found that 75% of the high dominant men and
70% of the high dominant women took the leadership role in same-sex pairs. When high
dominant men were paired with low dominant women; however, 90% of the men became
leaders. When the woman was high and the man low, only 20% of the high dominant women
assumed the leadership role. These results show that women express their dominance in a
different manner than the men in the mixed-sex condition. In sum, the study highlights a key sex
difference: Men tend to express their dominance through acts of personal ascension whereby
they elevate themselves to positions of power and status. While women tend to be less oriented
toward personal striving for status over others, opting instead to express their dominance for
group-oriented goals.
Dominance Theory
Dominance theory was developed by Denise Cummins who started with the proposal that
the struggle for survival in human groups was often characterized by conflicts between those
who were dominant and those who were trying to outwit those who were dominant. Selection
will favor strategies that cause one to rise in dominance but also will favor the evolution of
subordinate strategies to subvert access of the dominant individual to key resources needed for
survival and reproduction.
This theory has two propositions: (1) Humans have evolved domain-specific strategies
for reasoning about social norms involving dominance hierarchies. These include understanding
aspects such as permissions, obligations, and prohibitions. (2) These cognitive strategies will
emerge prior to, and separate from, other types of reasoning strategies.
Evidence that supports the propositions made by this theory are summarized below: (1)
Children as young as age three appear to reason about dominance hierarchies, including the
property of transitivity; (2) people tend to remember the faces of cheaters more if the cheaters are
lower in status than if they are higher in status; and (3) people tend to look for violations of rules
among lower-status individuals when they are asked to assume the perspective of a higher-status
individual.
Social Attention Holding Theory
Paul Gilbert introduces another theory that emphasizes the emotional components of
dominance. His theory is partly based on Resource-Holding Potential, which refers to an
evaluation that animals make about themselves relative to other animals regarding their relative
strengths and weaknesses. The behaviors that follow from these relative assessments give rise to
dominance hierarchies. Three types of behaviors may follow in response to another individual:
(1) attack, (2) flee, or (3) submit.
Humans have adopted a similar mode called social attention-holding potential (SAHP).
This revolves around the quality and quantity of attention directed at an individual. In this
regard, humans are thought to compete with each other, to be attended to, and valued by, others
in the group. Differences in rank, therefore, result from the differences in attention—those high
in attention have high status, and those low in attention have lower status, respectively. In
addition, Gilbert suggests that humans bestow attention to those who perform a function that is
valued by the bestowers. People compete to bestow benefits on others, in this view, to rise in
SAHP.
Gilbert’s most novel theoretical contribution comes from hypotheses about the role of
moor or emotion as a consequence of respective changes in rank. An increase in rank produces
two emotional consequences: elation and an increase in helping others. Meanwhile, a decrease in
rank produces a different set of consequences for mood and emotion—the onset of social anxiety
(which occurs in situations where there is the possibility of gaining or losing of status), shame
and rage (as a response to status loss), envy (as a form of retaliation to motivate the acquisition
of what others have), and depression (to facilitate submissive posturing to avoid further attacks
from superiors). In sum, this theory proposes that many aspects of human emotional life are
evolved features of psychological mechanisms designed to deal with the adaptive problems of
status hierarchies.
Determinants of Dominance
A variety of verbal and nonverbal characteristics signal high dominance and status. These
range from time spent talking to testosterone. Correlation between dominance and status were
found; however, it is important to remember that causation cannot be inferred.
Verbal and Nonverbal Indicators of Dominance
One researcher found that dominant individuals tend to stand tall, face their group, place
hands on hips, expand their chests, smiling is minimal, they touch others, and speak in a loud and
low-pitched voice. Whereas, behaviors of low-ranking or submissive individuals is typically the
opposite: their posture is bent, they frequently smile, speak softly, look while the other is
speaking, they don’t interrupt others, and they address the high-status group members rather than
the group as a whole.
A separate study predicted a link between walking pace and status that would only occur
for men and not for women. This is because males overtime have had to compete for females by
impressing them with signs of their hunting skills, including locomotory speed and perseverance.
This study proved the hypothesis, yielding a significant correlation between walking speed and
socioeconomic status for men but not for women.
Size and Dominance
Sheer size remains an important factor. The term “big man” has a dual meaning in most
cultures, referring to both a man of large physical stature and a man of importance, influence,
power, and authority. This comes together in the human tendency for rank or social stature to
correlate with physical stature. People have a preference for leaders who are tall. This is shown
in a study where audiences described a man said to be high in status as taller than when the same
man was said to be low in status. In the United States, tall men also have an advantage in being
hired, promoted, paid, and elected.
Testosterone and Dominance
Testosterone is an androgen and perhaps the most important class of hormones that
contribute to the development and maintaining of “masculine” features. Sex differences are
apparent in the distribution of testosterone because men have significantly more when compared
with women. Scientists have suspected that testosterone is closely connected with dominance
and status. Evidence for this is in the finding that injections of testosterone in low-ranking
animals, subsequently increased their rank. For humans, higher testosterone levels have also
proven to be correlated with a variety of dominating behaviors. Further studies reveal that
changes in status result in changes in testosterone. In addition, mood changes accompany
testosterone changes. Both apply to athletes whose testosterone levels rise prior to a match and
continue to rise after winning a match, which is accompanied by elevated moods. Similar effects
have been documented for chess games, reaction time contests, and symbolic challenges via
verbal insults—winners show mood elevation, while losers experience a depressed mood.
The evolutionary function of these changes in testosterone is not known, but it is
speculated that winners need elevated levels of testosterone to prepare them for future contests.
They also may need elevation in self- confidence in order to confirm their higher-status role and
perhaps even fostering an increase in their sexual access to women. Meanwhile, the decrease of
testosterone in losers may function to prevent future injury by discouraging future confrontation.
A final, and more direct link between testosterone and dominance implicates the waist-tohip ratio (WHR) of men. The WHR seems to be dependent on testosterone, and men with a
higher WHR are generally healthier and have fewer health problems. The are also more often
judged as leader-like and dominant.
It is important to note that this area is underdeveloped and requires further research and
confirmation of speculations with respect to evolutionary theory. Also, it is important to note that
research on women with respect to testosterone levels is limited and further research is needed in
order to attempt to draw a link between testosterone and female status. However, in sum, higher
testosterone levels in men might lead to dominating behaviors that lead to high status in some
subcultures. But reciprocally, elevations in status appear to lead to rises in testosterone levels.
Serotonin and Dominance
Serotonin joins testosterone as one of the brain chemicals responsible for mediating one’s
position in the status hierarchy. Male monkeys with high social rank and fraternity officers had
more serotonin in their blood, when compared with low-ranking monkeys or normal fraternity
members. As with testosterone; however, causal paths can run in both directions and serotonin
levels will change if the situation allows for a change in status. In other words, when alpha males
were overthrown, serotonin levels were reduced and when lower-ranking males ascended power,
serotonin levels increased.
Needed: A theory of the Determinants of Dominance
Still, a broad theory in this area is lacking and there are several questions that remain to
be answered by cross-cultural research on prestige, status, and reputation.
Self- Esteem as a Status Tracking Mechanism
Evolutionary psychologists have increasingly become interested in emotional and selfevaluative psychological mechanisms that track adaptively significant dimensions of social
contexts. Derived from this idea, the sociometer theory was developed and is based on the idea
that self-esteem functions as a subjective indicator or gauge of other people’s evaluations.
Humans evolved in groups and needed others to survive and reproduce. This prompted
the evolution of motivations to seek the company of others, form social bonds, and curry the
favor of others in the group. Failure to be accepted by others could have resulted in isolation and
premature death. Thus, social acceptance would have been critical to survival and selection
would have favored a mechanism that enabled an individual to track their degree of acceptance
by others. Self-esteem is this mechanism. This theory has been expanded to serve several
evolutionary functions: (1) It could serve as a motivational mechanism to encourage individuals
to repeat or increase the frequency of actions that lead to a rise in the respect they received from
others; (2) It could guide decisions about whom to challenge and whom to submit; and (3) It
could lead to the tracking of one’s desirability in the mating market and hence the relative mate
value of those to whom one devotes mating effort.
Strategies of Submissiveness
There are adaptive problems posed by being low in status, it is important to consider
these problems.
Sex Differences in Submissive Strategies
One study examined sex differences in negotiating with doormen at nightclubs. The
results suggested sex differences in tactics used to negotiate with powerful men, with tactics
triggering sexual motivation in powerful men one means available to women.
Deceiving Down
This topic considers people who are stuck in a position that they perceive as below their
capabilities or beneath their station. This placement could create hostility in the relationships and
subsequent destruction of the relationships. Therefore, the adaptive solution of deceiving down
may come into play. This involves an actual reduction in self-confidence in order to facilitate
acting in a submissive, subordinate manner. Evolutionarily this serves a function because it is
considered affective for one to appear nonthreatening to those who are dominant.
The Downfall of “Tall Poppies”
A tall poppy, in general, is a special and successful person who attracts the envy of
others. The subordinate position comes with a cost that is combated through subordinate
strategies. A subordinate may disparage a more successful competitor in order to lead to other
outcomes, such as reputational damage to the competitor and redirection of one’s efforts toward
a different arena. One study showed how subordinate people take pleasure in the fall of a tall
poppy in several important conditions. The available evidence suggested that one submissive
strategy is to facilitate the fall of those with greater status and to take delight in their fall. The
pleasure that people feel in a rival’s misfortunes might act as a motivational mechanism to
promote those misfortunes. Because evolution by selection always occurs on a relative basis—
one’s success relative to others—we expect two general strategies of getting ahead in status and
dominance hierarchies. One is self-enhancement, or attempting to achieve something relative to
one’s competitors. The other is to promote the downfall of others.
The Selfish Gene
Chapter 12 Summary
Summary By Stacey Hewitt
In Darwinian terms, a nice guy is one who assists other members of its species to help
pass their genes to the next generation. According to this definition, nice guys would decrease in
number until they ultimately became extinct. If a different definition of nice is used, it may not
be the case that the nice guy finishes last, but rather finishes first. The Prisoner’s Dilemma can
be used to grasp a better understanding of altruistic behaviors amongst non-kin. Dawkins uses
the example of birds picking ticks off of each other to illustrate this point. If a bird A picks ticks
off the head of bird B, it only seems fair that bird B returns the favor when needed. Returning
this favor would require time and energy and if bird B can get away with cheating and not
returning the favor, he can get the benefits without incurring the costs. Bird B can either
cooperate or cheat or both birds could defect and refuse to pick ticks off of each other. This
creates a prisoner’s dilemma. This is example of an iterated game because it will occur over and
over again. (the birds will constantly need ticks removed).
A strategy for solving this dilemma is Tit for Tat in which individuals cooperate on the
first move an thereafter simply copy the previous move of the other person. For example, bird A
will pick ticks off of bird B at first, but if next bird B does not return the favor, bird A will stop
helping bird B get off ticks because he is copying this unhelpful behavior. Tit for Two Tats is
another strategy in which an individual defect twice in a row before the other person retaliates.
Going back to the bird example, bird A would allow bird B not to return the favor twice before
he would stop helping out bird B. These types of strategies can be characterized as forgiving
strategies because it retaliates but has a short memory. That is, it is quick to overlook cheats. In
general, nice strategies that forgive do better than nasty strategies.
How successful a strategy is depends on what other strategies are being used, or the
climate. For a strategy to remain successful it must do well in a climate where it is numerous. In
order for a strategy to be an ESS it must not be invadable by other rare strategies. Because this is
not the case for Tit for Tat, it is not an evolutionary stable strategy because it could be invaded
by another nice strategy. It is instead referred to as a collectively stable strategy. More than one
strategy can be collectively stable at the same time. Tit for Tat is in fact more stable than an ESS
because it allows for clustering. Tit for Tat can also be characterized as non-envious which
means the individual is happy if the other player wins just as much as they do, as long as both
players win.
There are two types if games, zero-sum and nonzero sum. Zero sum games are those in
which a win for one player is a lose for the other player. The Prisoner’s dilemma is a non-zero
sum game because both players can win. Non-zero sum games can be mutually beneficial.
Modern day lawsuits are typically zero sum games for the clients and non-zero sum games for
their lawyers. Sports are typically zero sum games because spectators would much rather watch a
fierce competition then players behaving amicably. Humans, and also plants, animals, and even
bacteria use the Tit for Tat strategy to solve the Prisoner’s Dilemma.