Ana Arias

Christine Hansen

Brooke Smith

A Mind of her own

The evolutionary psychology of women

Anne Campbell

 

Chapter 3

High stake and low risks: Women and aggression

 

            There are significant sex differences in the areas of aggression, status seeking, group formation, risk taking, and self-esteem that can be explained by only the males’ need to compete for mates, not the females’.  Females naturally became the evading sex, meaning that their mind set was determined by the fact that they were not males (64).  Female competition was kept in balance by the mothers’ need to guarantee her own survival and her reproductive investment.  In order to fix the theoretical gender balance, one must look at the three premises that have been used to explain aggression and risk taking in terms of the sex differences.

The first premise states that the want to mate with many females causes strong male competition.  Men are always going against each other to try to be the victor in the gene pool of the next generation.  “The disparity between male winner and losers is great.  Men who win, win very big.  Those who lose, leave no descendants whatsoever” (64).  The variance in reproductive success among men is a lot larger that in women.

Men are much more willing to risk their lives in competition because the reproductive rewards are greater for them, as suppose to females.  Interestingly though, the majority of men almost everywhere have monogamous marriages.  This is either because it is the law in that area or because very few men have the resources needed to support more than one wife, even if polygamy is legal there.  Also, recent studies have shown that the advantages of male dominance are not as big as people might have thought.  This is due to the important role of female choice in choosing a mate (66).

Female choice can sometimes counteract what the male is trying to accomplish as far as copulating purposes go.  Females have their own agenda and likings and can use these to put a stop to a male’s attempt at copulation by not cooperating or by protesting noisily.  Some males will respond to an unwilling female by trying to remove and replace her current pursuer.  Even if a male does achieve this dominance in the mating game, it might be brief and not very helpful to his reproductive success.  He could be right back at the bottom of the chain just as quickly as he rose to the top.  Success also depends on other factors.  “Success depends not only on insemination and infant survival but also on the extent to which the progeny attain adulthood and are successful reproducers themselves” (69).  A male who has offspring that don’t reproduce has simply failed at his mission for long term reproductive success.  Monogamy can actually help ensure offspring survival, especially with females.

            The second premise states that male competition cause’s generalized taste for risk.  As a consequence of the mating competition, in general risk taking is higher in males than in females.  One factor that contributes to this is advertising because it is a useful strategy that increase’s a male’s chances of winning in competition.  The more fearless a male appears to be, the more other males will back down from him (70).  Risk taking becomes generalized to non-competitive conditions and a critical component of advertising is that it has more success when done in public places.

Men’s precarious behavior comes from their lack of concern with their own wellbeing compared to that of women.  This is the basis for men’s “greater involvement in gambling and drug use, and their greater vulnerability to injury and death from external causes, especially car accidents” (70).  Women are more fearful of illness than men are, and rate the importance of health care much higher than men do.  Men also show less of a fear for crime than women do.  Men are much “more willing to walk unaccompanied in unlit and dangerous areas of cities despite the fact that men are more likely to be victims of crime than women.” (70)

The third premise states that the rewards of female competition are low.  According to the male based argument, women have lower aggression because they do not need to battle with each other in order to copulate.  Men and their natural want for sex pretty much anytime and anywhere means that they will coerce any woman seeking sex.  Women have little to gain from mating with many males.  Once she is pregnant, other copulations will not make a difference in the number of offspring she has during that time.  Females compete for all the resources they need to help their pregnancy move along properly and to raise their offspring once they are born.  The main resource they fight for is food (71).  A woman’s reproductive success depends heavily on her ability to provide food to her children.  Overall, female aggression is much less than male aggression.

Men are more competitive for copulation rights because if they fail they lose out in spreading their genes to the next generations.  Women are more competitive concerning each of their offspring’s well being because they have similar reproduction rates.  “Females’ high parental investment means fewer children, and fewer children mean greater competition because so much rides on each one of them” (72).  A female, unlike a male, should not put her life on the line for copulating, but she should be very competitive about the survival of any child born.  She is competing in an environment in which the survival of just one more offspring could make a large difference in reproductive success.

The overall nature and mind set of females depends on the winning strategies of past generations.  Something in past years has essentially programmed women not to be as aggressive or as competitive as men.  Evolution has also created women to survive longer.  This is because whichever sex provides the most parental care should be selected by nature for better longevity so they can protect their offspring to maturity.  “Sex differences in life expectancy favored whichever sex took the most parental responsibility” (73). 

An emotion that explains restraint from aggression is fear. It affects the high weight and costs put on women’s physical combat.   Fear tells the mind to move away from certain situations.  “The decision to withdraw is made when fear is the predominant emotion” (74).  Women are more inclined to overreact to closed spaces in which they could be trapped, open spaces in which they could be in danger, and any predator that might cause injury or death.  This sex difference could have resulted from nature selecting and adjusting to two kinds of mechanisms, a sensation seeking attitude and an absence of fear.  “Females lower risk taking resulted from a sex difference in the magnitude of what could be gained by aggression and consequent differences in sensation seeking” (77).  Fear is a negative motivational state that drives “avoidant behavior” while sensation seeking is a positive motivational state that drives “appetitive behavior”.  Fear makes people avoid situations, and sensation seeking makes people approach situations.

 

The biology of fear and sensation seeking

Monoamine transmitters are responsible for the monitoring incoming information and prioritizing it. “Various monoamines jointly infiltrate the whole brain but each travels along its own it own unique path with its own receptors” (79). The receptors activate second-messenger proteins that alter the postsynaptic cell and generate activity among other proteins located within the cell. Activating these proteins can “trigger gene-switching transcription factors leading ultimately to long-term changes within the cell’s behavior”(79).

“The amygdala has been strongly implicated in emotion and specifically in the emotional tagging of memory representations of the world” (79). Research done by Joseph LeDoux have clarified the pathways and functions of the amygdala in fear, he trained animals to anticipate an electric shock at the sound of a tone. The tone was supposed to provoke all the behavioral signs of fear. By starting at the brain, he worked along the neural path to the innermost part of the brain. “At each stage he ablated or destroyed the tissue so that he could establish at what point fear no longer appeared”(79). LeDoux found that, “what was critical was that the incoming neural impulses, after reaching the sensory thalamus, were passed to the amygdala”(79). When that connection was broken, the fear response disappeared. The study found that the amygdala was receiving a message to ‘be afraid’, although there was never a noise that had been registered in the cortex. “The central nucleus of the amygdala is critical for every measure of conditioned fear-behavioral freezing, autonomic responses, stress hormone release, pain suppression and reflex potentiation- and each one of these is controlled by a different output from the amygdala”(80). Because this system is fast, it can allow for an immediate reaction to a fear-provoking event without conscious recognition of danger. “At the same time in the prefrontal cortex these images are given emotional ‘tone’ resulting from the recognition of the original primary emotions that were experienced at the same time these images were placed in memory”(80). We have a representation of the experience and the emotion but without the amygdala we cannot ‘re-feel’ the emotional component without the amygdala. This is why when we sometimes remember a very frightening experience we cannot help but physically wincing at the memory.

            Decision making weighs heavily on ‘secondary emotions’. Damasio has called them ‘somatic markers’ and “they are our autonomic ‘gut’ reaction to a prospective state of affairs”(80). When a decision has to be made we rarely have time to weigh the pros and cons, so we usually go with what memory has tagged the experience with. “According to the incentive theory, risk taking is positively tagged for males-they seek it out” (81). It is believed that females are less likely to take risk because they are negatively tagged. It is important to look at the emotional aspect of the tagging.

             Noradrenaline is the chemical messenger of the sympathetic nervous system and sudden danger can increase the firing rate of noradrenaline by up to ten times its normal rate. “While the body is primed by the sympathetic nervous system, the brain is woken up too by simultaneous activity of the locus ceruleus”(81). Some of the earliest neurochemical work examined the role of noradrenaline on aggression. Rats that were placed on electrified grids rear up and fight, and in turn produce large amounts of noradrenaline. The problem was that this rearing up is a very specialized form of aggression. “It seems likely that the noradrenaline rise that the rats show is not correlate of aggression per e but simply of fear”(81).

            Some have argued that “one particular form of human aggression is in fact associated with a lower than normal fear response”(82). Individuals with antisocial personality disorder usually have a lower fear response than normal. Because of these low levels, “they fail to learn from punishment and show a callous disregard for the safety of both themselves or others”(82). “It is rare indeed that a woman’s fear response shows this kind of suppression and in evolutionary terms it is unsurprising-such a careless disregard for her own safety would certainly have compromised the survival of her offspring”(82).

            The principal function of the noradrenergic system is to raise the psychological and bodily alarm signal. “The feeling alert us to danger but they do not tell us what to do about it”(82). It is important to note that noradrenaline does not guarantee aggression any more than it “guarantees running away or freezing”(82). The alarm reaction is necessary for our own safety. “And the system malfunctions more in males than females, suggesting that in men evolutionary pressures have not been great enough to correct it”(82).

“Serotonin is chemical pathway of behavioral inhibition and has been more closely and directly linked to aggression than noradrenaline”(83) Serotonin tailors responses to the demands of situations preventing overreaction. Research has shown that aggression is always the last line of resort because it can be very painful and dangerous. “The chemical that holds us back from aggression is serotonin”(83). Low levels of serotonin seem to increase aggression by blocking our ability to inhibit impulsive behavior. Valzelli and co-workers did research with mice and found that “as their aggressiveness rose their serotonin levels dropped”(84). Further research has suggested that serotonin is “especially associated with impulsive aggression”(84). This proved to be true when research was done linking serotonin to suicide. Scientist found that suicidal patients had lower levels of serotonin. This research found that, “lower serotonin is the source of male aggression and risk taking”(85).

There are sex differences in this particular neurotransmitter. A recent study concluded that “women displayed significantly higher presynaptic serotonin activity than men- especially in the frontal cortex that is responsible for behavioral inhibition”(85). These is true because women have always been know to control social and emotional impulses. 

            “Male sexual behavior is influenced by both dopamine and serotonin but each of these transmitters acts in opposing and unique ways”(86). Dopamine is known as the ‘feel good’ system and it is important in sexual motivation. During mating dopamine levels rise and introducing a female increases dopamine levels event further. Males have to be “ready, able and eager to perform sexually” in order to be a successful reproductive male (86). “Serotonin- the ‘don’t rush into things’ chemical- impairs his ability to do this. Male than gave up some behavioral reserve in order to gain a higher sexual drive”(86). This may imply that other aspects of male behavior have been affected by the dampening of the “serotonergic system- including their ability to inhibit risk taking”(86).

 Dopamine is the chemical that underlies both liking and wanting. “Dopamine elevation is associated with positive affect- feeling good”(89). Johnson and Tversky did research and found that individuals that are dopamine-high are less likely to take risk. For example, in a fight they would not choose to fight because the will be disappointed if they loose. They are already happy and loosing would only cause them distress. Low levels of dopamine make people seek out excitement. Individuals seek out other “new and stimulating experiences in order to boost their arousal (or dopamine) to pleasurable levels of sensation seeking”(89). But these finding have not been supported by recent studies. Zuckerman, who has devoted his life to studying sensations seeking, notes, “aggression is not a high correlate of sensation seeking”(90). The association between low levels of dopamine and search for excitement has not been found.

 

Women, competition and low risk-aggression

Fear is what keeps females at a less lethal level of competition than that of males. Females still need to compete. There are two forms of low-risk tactics that females use. 1. An unwillingness to escalate to direct combat 2. A preference for indirect rather than direct forms of aggression. Meta-analysis is a statistical technique that combines studies to estimate the magnitude of the sex differences based on thousand of subjects. Meta-analysis confirms that the sex difference is greater for physical aggression than for verbal/psychological aggression. Using meta-analysis it was found that the smallest sex difference for physical aggression was that 62 percent of men are more aggressive than the average woman, while the largest finds that 82 percent of men exceed the average woman. With verbal aggression it was found that there was no significant sex difference. It is suggested that 69 percent of men are more aggressive than the average woman.

            Eagly and Steffan did an experiment and concluded that women have a general tendency to experience greater fear than men do in relation to anger-provoking situations. It was concluded that the greater the danger and anxiety the female feels the less likely she is to be aggressive. Men and women faced objectively the same situation and yet males showed less fear and more aggression. For men, provocation raised their levels of aggression and it did so equally for verbal and physical aggression. For women, provocation had a much greater effect on their willingness to be verbally aggressive than on their willingness to risk physical aggression. The ironic part is both men and women have anger, and it had been recorded that both sexes are “angry” six times a week. The sexes do not differ in the intensity of their anger that they feel. Women are reluctant to express their anger as an upright physical attack but there are other ways of competing.

            Indirect aggression is one way that females compete, it is a form of social manipulation where the target is attacked indirectly and the aggressor can therefore remain unidentified. Some examples of indirect aggression are shunning, stigmatizing, and gossiping. It excludes rivals and destroys their reputation without a head on confrontation and it is one form of aggression in which females exceed males. Girls are more likely to exclude newcomers than are boys. This form of aggression starts in girls as they polish the social and verbal skills necessary for this invisible form of victimization. By the age of eleven girls are higher than boys on becoming friendly with someone as a way of revenge, gossiping, and a way to suggest shunning another. Studies of school bullying also report that girls employ indirect strategies of stigmatization and exclusion that often has a devastating effect upon the victim. This form of aggression continues into adulthood. Investigating victimization in the workplace found that women more than men use indirect forms of aggression such as spreading false rumors, and not speaking. An ethnographic study in Buenos Aires concluded that women are extremely competitive envious of each other, and female competition is expressed through comparisons regarding clothing, and appearance.  

            Primate females also use indirect aggression. Females have been observed harassing other females for days or weeks and interrupting her when she is trying to rest, feed, or mate. This harassment takes its toll on the female by causing stress and can even cause abortion. These indirect tactics diminish the reproductive success of the victim; therefore there are more resources for the victor and her offspring.

 

Maternal aggression-a predictable paradox

There is one clear situation where the pay offs for aggression by females are much larger than that of males-saving her child's life. The life of her offspring has cost the mother much time, and effort. The cost for the male is a few minutes of his time and easily replaceable sperm. The cost of replacement for the mother is measured in years while the father is measured in minutes. Maternal aggression has been documented in many species, and it occurs when another animal approaches or interferes with one of a female’s offspring. The species in which it has been documented are those where male infanticide is a serious threat to female reproductive success. The mothers attack is ferocious and immediate, in these species the females are extremely sensitive to the presence of males near infants and when an infant shows distress a nearby male may be attacked even if he has displayed no aggression towards it. Maternal aggression begins during pregnancy and continues through lactation, suggesting a strong hormonal component. The duration of maternal aggression corresponds with the period when the young are most vulnerable. It disappears when the pups are removed for five hours but it is restored five minutes after the pups are returned. If the pups are attacked or killed, maternal aggression switches off immediately. The severity of maternal attack is directly related to the size of the litter that the female is protecting. In primates threats to the infant come from other females as well as infanticidal males. Females will start pulling, rough handling, kidnapping and using direct aggression towards the young. In these species females display a dominance hierarchy that is based on matrilines. High ranking females of course have little to fear from low ranking females. This leads to a distinct pattern of maternal protection of young that depends on the females’ standing in the group. Low ranking females protect their infants by restraining them, high ranking mothers give their offspring greater freedom because they have less fear from launching an attack on any low ranking female that tries to abuse them.

            There are two types of theorists. The first type are called the high-fear theorists who believe that it is extreme levels of fear that switch on the severe form of aggression used by mothers. The second type are called the low-fear theorists who believe that it is a temporary reduction in fear that enables the mother to attack with such ferocity. The high-fear theorists make a distinction between two forms of aggression. Offensive aggression is used by female rodents principally against other females and these attacks rarely cause severe injury. These attacks on females by females seems to be a warning to the female intruder to get away from the space she considers her own. These attacks involve a very low level of fear on the part of the aggressor. However, females show a very different response to a male intruder because they are far more likely to have infanticidal intent than females. A dispute with a male isn’t about the space but about her pups survival. Here the female uses a defense attack and it takes a much more serious form. When the mother attacks a male it is a vicious attack without warning or the use of threats. High-fear theorists believe that when fear is high, the attack is defensive and severe, when the fear is lower the attack is offensive and serves to warn off the opponent. The high-fear theorists have a view that maternal aggression is an adaptation that depends on fear. Mothers launch their lethal assaults not despite the fear but because of it.  Low-fear theorists see aggression as a straightforward continuum from mild to severe. they believe that the more fearful the animal is the less likely it is to launch a severe attack. It is there fearlessness that opens the door for aggression. It was found that mice from genetic lines that show high levels of aggression also show lower levels of anxiety, and a high level of anxiety is inversely related to the probability of showing maternal aggression.

            Oxytocin is a neuropeptide made in the hypothalamus that stimulates the contractions that expel the infant from the uterus. It is responsible for the milk letdown and is triggered by the nipple stimulation of suckling. Oxytocin has been called the love and bonding hormone. It has a very special affect on mothering . Psychologically, Oxytocin promotes a feeling of well being and tranquility. It enables the growing sense of love and attachment to the infant. The more the infant suck the more Oxytocin is produced. Evidence from animals suggests that Oxytocin decreases blood pressure and can even block the experience of pain. Oxytocin seems to be a de stressing hormone that activates the parasympathetic nervous system responsible for keeping basic body functions ticking over in a relaxed state. In mothers it increases their attachment to their infant, promoting the feeling of love, and makes her infant more valuable to her. It also suppresses the fear that would normally cause her to back off from threat.

 

Fear and fitness

The difference between men and women in their willingness to move from conflict to violence is tied to the reproductive strategies of the two sexes. With males physical aggression has brought rewards that outweighed the risks. Males are more concerned with reproducing rather than their own survival and well being, therefore they will risk their own life for a chance to reproduce. Physical aggression for males intimidated other males and in doing so, won the victor status. The more successful he was the greater freedom he had, not only to claim fertile females but also to monopolize over disputed resources and food. For females aggression has costs that males do not have to face. For females injury or death means the loss of her current offspring. For these reason females avoid unnecessary conflict and stay away from physical aggression-both threaten the huge investment that a woman had made in rearing her dependent young. Anne Cambell believes that the mechanism that underlies the sex difference of aggression is fear. “For males, low levels of fear open the door to extravagant displays of bravery and combat that can be used to achieve a reputation in the community. The prize is status and all the benefits that come with it.”

 

A Mind of Her Own: The Evolutionary Psychology of Women

By: Anne Campbell

 

I.                    High Stakes and Low Risks: Women and Aggression

A.     Sex differences

1.      Females became “the default sex” meaning their psychology was determined by the fact that they were not males.

2.      Female competition was kept in check due to mothers’ need to ensure her own survival and reproductive investment.

B.     Dominant males get the biggest prizes.

1.      The desire to mate with multiple females causes intense male competition.

2.      The variance in reproductive success among men is greater than it is with women.

3.      Females prefer friendly males both as sexual partners and as group leaders.

C.     Male competition cause’s men’s generalized taste for risk

1.      As a consequence of mating competition, risk taking in general is higher in males than in females.

2.      Men’s risky behavior comes from their lack of concern with their own safety compared to that of women.

D.     The rewards of female competition are low

1.      Women’s aggression is lower because they do not need to compete with each other in order to copulate.

2.      Women’s success depends on their capacity to provide their offspring with food.

3.      Female nature depends on the winning strategy in past generations.

4.      Whichever sex provides the most parental care should be selected for longer survival in order to guard their reproductive investment to maturity.

E.      The female adaptation – fear

1.      An emotion that explains restraint from aggression is fear because it affects the high weight and costs put on physical combat. 

2.      Fear is a negative motivational state that drives “avoidant” behavior.

II.                Monoamine Neurotransmitter Family

A.     Role in the brain is to monitor incoming information and prioritize it.

B.     Without them the brain would be overwhelmed by information and would not know which activities to do first

C.     Path of the Monoamines

1.      carry messages from base in brainstem and midbrain

2.      move forward to amygdala and other subcortical structures, and react instantaneously to emotion-laden stimuli

3.      then to frontal cortex where slower more reasoned response can be prepared

4.      travel back to cerebellum and spinal cord and relay message to muscles and viscera

III.             Anatomy of Aggression

A.     Hypothalamus is the important structure for aggression

 

1.      receives incoming information from the amygdala

 

2.      this information travels along a pathway called the bed nucleus of the stria terminalis

 

3.      messages from the amygdala either turn the “volume” up or down  on aggression

 

B.     Amygdala

1.      implicated in emotion and emotion tagging of memories

2.      incoming messages go to the lateral nucleus and activates the behavioral control system

3.      central nucleus is critical for every measure of conditioned fear

4.      humans amygdala damage cannot be conditioned to fear and are unable to recognize fear on the faces of others

C.     Noradrenaline

1.      chemical messenger of the sympathetic nervous system

2.      responsible for the ‘panic’ feeling

3.      source of noradrenaline is the locus cerelus

4.      noradrenaline rise is not a product of aggression, but rather of fear

D.     Serotonin

1.      chemical pathway of behavioral inhibition

1.      closely and directly linked to aggression

2.      chief function is to tailor responses to the demand of the situation preventing overreaction

3.      aggression is the last resort, because it is painful and dangerous

4.      low levels of serotonin increase aggression because of its ability to inhibit impulsive behavior

1.      aggression is impulsive, thoughtless, and immediate

5.      studies have linked serotonin to suicide

1.      people with lower levels of serotonin were more prone to commite suicide

2.      a failure of inhibition resulted in more violence

6.      SEROTONIN IS THE SOURCE OF MALE AGRESSION

 

IV.              Sex Differences

 

A.     Women displayed significantly higher presynaptic serotonin activity than men

1.      especially in frontal cortex that is responsible for behavioral inhibition

B.     Women are better controlling social and emotional impulses

C.     There is no difference between the sexes in cognitive inhibition

 

V.                 Neuroscience of sexual behavior

 

A.     male sexual behavior influenced by both dopamine and serotonin

1.      each neurotransmitter acts in opposing and unique ways

 

B.     Dopamine

1.      the ‘feel good’ system

2.      dopamine levels rise during mating

3.      dopamine is the chemical that underlies both liking and wanting

 

VI.              Positive Association between Dopamine and risk-taking behaviors

 

A.     Basic Question: Is Aggression itself a pleasurable experience?

1.      research suggest that there is little pleasure in fighting

B.     L-dopa

1.      dopamine precursor which seemed to heighten aggressive behavior in mice

2.      in reality, it increased defensive reactions to painful stimuli and suppressed normal fighting behavior

C.     Dopamine increases the rewardingness of exploration and novelty

D.     Elevation of dopamine is associated with positive affect-feeling good

1.      its depletion is associated with a flattening of emotion

E.      Dopamine-high individuals are more likely to think that they can win a fight

1.      but individuals with high dopamine levels anticipate that they would feel more distress if the lost

2.      so, they avoid taking risk

 

VII.           Negative Association between Dopamine and risk taking behaviors

 

A.     Low levels of dopamine make people seek out excitement

B.     Individuals with a poor ability to bind dopamine have higher levels of sensation seeking

1.      these individuals seek other things to increase their arousal to pleasurable levels

2.      low levels of dopamine are linked to aggression

 

VIII.         Women, competition, and low-risk aggression

 

A.     Fear and female aggression against other females as well as males

 

B.     Two forms of low risk tactics that females use.

 

 

 

IX.              Meta analysis

 

A.  Meta analysis is a statistical technique that combines studies to estimate

the magnitude of the sex differences based on thousand of subjects.

 

B.     Meta-analysis confirms that the sex difference is greater for physical aggression than for verbal/psychological aggression.

 

C.  Study done using meta analysis, showed males more aggressive than

females

 

X.                 Eagly and Steffan

 

     A.  They conducted an experiment and concluded that women have a general

tendency to experience greater fear than men do in relation to anger-provoking situations.

      B.  For men, provocation raised their levels of aggression and it did so

equally for verbal and physical aggression. For women, provocation

had a much greater effect on their  willingness to be verbally

aggressive than on their willingness to risk physical aggression.

 

C.     The sexes do not differ in the intensity of their anger that they feel.

 

XI.              Types of aggression

 

A.     Indirect aggression is used by females. Examples would be shunning, gossiping etc.

B.     This form of aggression continues into adulthood. An ethnographic

      study in Buenos Aires concluded that women are extremely competitive

      and envious of each other, and female competition is expressed

      through comparisons regarding clothing, and appearance.  

C.  Primate females also use indirect aggression. These indirect tactics          diminish the reproductive success of the victim; therefore there

      are more resources for the victor and her offspring.

 

XII.            Maternal aggression- a predictable paradox

 

A.     Maternal aggression has been documented in many species, and it occurs

when another animal approaches or interferes with one of a female’s   offspring       

B.     Maternal aggression begins during pregnancy and continues through

lactation, suggesting a strong hormonal component

                  C.   The severity of maternal attack is directly related to the size of the

litter that the female is protecting.

 

                  D.  Females will start pulling, rough handling, kidnapping and using direct

aggression towards another females young. In these species females display a dominance hierarchy that is based on matrilines.

 

VI. Two types of theorists

 

                  A.  The first type are called the high-fear theorists who believe that

it is extreme levels of fear that switch on the severe form of

aggression used by mothers.

       

                  B.  The second type are called the low-fear theorists who believe that

it is a temporary reduction in fear that enables the mother to attack

with such ferocity.

 

                  C.  High-fear theorists believe that when fear is high, the attack is

defensive and severe, when the fear is lower the attack is offensive

and serves to warn off the opponent.

 

                  D.  Low-fear theorists see aggression as a straightforward continuum

from mild to severe. They believe that the more fearful the animal is

the less likely it is to launch a severe attack.

 

VII.    Oxytocin

 

                 A.  Oxytocin is a neuropeptide made in the hypothalamus that stimulates the

contractions that  expel the infant from the uterus.

 

                 B.  Oxytocin has been called the love and bonding hormone.

 

                 C.  Oxytocin seems to be a de stressing hormone that activates the

parasympathetic nervous system responsible for keeping basic body

functions ticking over in a relaxed state.

 

VIII.   Fear and fitness

 

                A.  The difference between men and women in their willingness to move

          from conflict to violence is tied to the reproductive strategies of the

          two sexes

                B.  With males physical aggression has brought rewards that outweighed the

          risks.

    C.  Females avoid unnecessary conflict and stay away from physical

          aggression-both threaten the huge investment that a woman had made

                      in rearing her dependent young

 

               D.  Anne Cambell believes that the mechanism that underlies the sex

        difference of aggression is fear.