Tim Devereaux

Ashleigh Anderson

Margaretha Kasim





Fisher, H. (2000).  Lust, Attraction, Attachment:  Biology and Evolution of the Three Primary                            Emotional Systems For Mating, Reproduction, and Parenting.  Journal of Sex Education                                                    & Therapy.  25(1), p.96-103.  Retrieved September 24, 2002 from EBSCO Host database                                     on the World Wide Web: http://web19.epnet.com.



            Fisher’s (2000), article examined human selection of mates and the drives that evolved to what they are today. Fisher (2000) examined three separate systems, that could work together but are separate entities, that have evolved in human brains. The three systems are Sex drive or lust, attraction and attachment (Fisher 2000). In this article, separate neurotransmitters were identified as contributors to each system.

            Fisher (2000) argues that these three emotional systems were used for mating, reproduction and parenting. Sex drive or lust, “is characterized by a craving for sexual gratification; it is associated primarily with the estrogens and androgens. The sex drive evolved principally to motivate individuals to seek sexual union with and appropriate member of the species” (Fisher, 2000, pp. 97). The attraction system, passionate or obsessive love is, “characterized by increasing energy and focused attention on a preferred mating partner…feelings of exhilaration, intrusive thinking about the love object, and a craving for emotional union with this partner or potential partner” (Fisher, 2000, pp. 97). Fisher (2000) speculated that this system evolved to facilitate mate choice, which enabled individuals to choose between mating partners and focus their attention on genetically superior individuals. The final system termed the attachment system, “is characterized by…feelings of calm, security, social comfort, and emotional union…This emotional system evolved to motivate individuals to engage in positive social behaviors and/or sustain their affiliative connections long enough to complete species-specific parental duties” (Fisher, 2000, pp. 97).

            Fisher (2000), stated that these systems regularly act together with other bodily systems and with each other. For example a person may start a sexual relationship merely for pleasure, then feelings may develop between the two people (Fisher, 2000). However, these systems may act totally independently of each other. For example a person could have an attachment with a spouse while may feel attraction or lust for someone else, or merely a picture of someone else (Fisher, 2000).



Lust or sex drive has long been regarded as a drive that is innate, or unlearned. It is common to all birds and all mammals alike. It is associated with androgens in both men and women. It is also associated with primary neural structures in the avian and mammalian brain (Fisher, 2000). While all animals experience the sex drive, there is still a preference of which mates to accept and which to avoid, suggesting that the sex drive and the attraction systems are separate (Fisher, 2000). This separation of all three systems is seen more clearly in humans. “…Humans can express sexual desire toward individuals to whom they are not emotionally attached, and they can feel deeply attached to a mate or spouse for whom they have no sexual desire” (Fisher, 2000, pp. 98).

It has been shown that men with higher levels of testosterone, which increases the sex drive, have less desire to form and attachment. “Men with high baseline levels of testosterone marry less frequently, they are more abusive during marriage, and they divorce more often” (Fisher, 2000, pp. 98). This negative relationship between testosterone and attachment can help us to understand why individuals in long-term relationships express less sexual interest in each other (Fisher, 2000). In these relationships levels of vasopressin and/or oxytocin may increase which will decrease the levels of testosterone (Fisher, 2000).



            Attraction is related to sex drive, but serves a separate purpose. Referred to as romantic love, passionate love, infatuation or obsessive love, attraction is common to all birds and mammals (Fisher, 2000).  Attraction is a drive that serves to focus attention on the best mating partner and pursue this potential mate (Fisher, 2000). Fisher (2000) suggested that romantic attraction is associated with high levels of both norepinephrine and dopamine, while serotonin levels are lowered.

            When a person falls in love they tend to only focus on the positive qualities of their mate. They tend to believe that their object of love is unique and there are often no thoughts of being with another mate. This could be due to the increased levels of dopamine in the CNS (Fisher, 2000). “This tendency to focus on, remember, and cherish specific traits of the beloved, as well as the tendency to focus on specific moments associated with the beloved, are additional indications that dopamine is involved in the feeling of romantic attraction” (Fisher, 2000, pp. 99).

            A person that is in a new relationship tends to reorder their lives and priorities, change their clothing, mannerisms, habits and values in order to become available to the loved one (Fisher, 2000). They also tend to experience higher than normal levels of jealousy if they suspect infidelity. Fisher (2000) explained this as an adaptation, that functions in order to drive away other suitors.



            Attachment is seen in mammals as behaviors such as maintaining proximity and displaying separation anxiety when they are apart (Fisher, 2000).  Feelings of closeness, security, social comfort, peace and mild euphoria when in contact with a partner, were all reported by individuals with a secure attachment (Fisher, 2000). There is data that vasopressin and oxytocin are released in the CNS that lead to feelings of attachment (Fisher, 2000).

            Attachment seems to play a large role in relationships. In polygamous societies fewer than 20% of men actually take two or more wives simultaneously, suggesting that when attachment is a factor, men prefer only one woman at a time (Fisher, 2000). Fisher (2000), implied that attachment was used evolutionarily as a way of protecting young offspring. When women began walking upright it was more difficult to carry children, and men were needed to offer protection (Fisher, 2000). It was also easier for a man to protect his offspring and his female companion if he wasn’t in charge of a harem of women, so one woman was ideal (Fisher, 2000).

            These three systems seem to have evolved independently, but still seem to serve an overall purpose while working together. Sex drive is found in all mammals and birds but sex will not take place unless there is an attraction. Attraction is a way for a person or animal to weed out those that are not worthy to have children with. Attraction can also help sort out any suitor that might not be worthy of an attachment. Attachment seems to be useful to raise young offspring and it also calms individuals and offers feelings of safety and peace.


Fisher, H. (2000).  Lust, Attraction, Attachment:  Biology and Evolution of the Three Primary                            Emotional Systems For Mating, Reproduction, and Parenting.  Journal of Sex Education                                                    & Therapy.  25(1), p.96-103.  Retrieved September 24, 2002 from EBSCO Host database                                     on the World Wide Web: http://web19.epnet.com.



I.  Emotions evolved for mating, reproduction, and parenting


II.  Sex drive (lust)- characterized by a craving for sexual gratification

(1)   Associated with estrogens and androgens to motivate individuals to find a partner for sexual union.

(2)   The urge for sexual consummation

(3)   Innate-common to all birds and mammals and associated with the androgen hormones and the interaction within the primary neural structures in the brain

a.       All mammals prefer to mate with some and not with others (Selection)


III. Attraction- characterized by increased energy and attention of potential mates

(1) Romantic attraction is a nearly universal phenomenon

(2)   Conservation of Energy- mammals conserve energy until they find a mate they choose to focus all their energy on

a.  Mate Choice- deciding which mate to focus energy on

(3)   Birds and Mammals evolution of body decoration for attracting mates for sexual copulation

a.       Triggers a specific “attraction circuit” in the brain, which the author claims has evolved for humans into romantic love.

(4)   Intrusive Thinking


IV. Attachment- characterized by close social contact and feelings of comfort

(1)   In birds and mammals- characterized by mutual territory defense, mutual feeding and grooming

(2)   In humans- characterized by feelings of calmness, and social comfort.

(3)   Associated with neropeptides, oxytocin and vasopressin

(4)   Motivates humans to maintain proximity and creates separation anxiety 

(5) Motivates humans to engage in positive social behavior and sustain affiliative relationships to complete parental duties


V. Emotions and Neurological Connections

            (1) Each emotion system is associated with a discrete collection of brain circuits

(2)   Chemicals within the brain correlated with emotions

i.   Catecholamines

ii.  Dopamine and norepinephrine

iii. Serotonin


(3) Measuring emotions in the brain

a.       Functional Magnetic Resonance Imaging (fMRI)

b.      Feelings of romantic attraction = high levels of dopamine and norepinephinrine and low levels of serotonin.


VI.  The Biology of Romantic Attraction

  1. Increased concentrations of dopamine in the nervous system are associated with heightened attention, motivation, and goal-directed behaviors
  2. Infatuation and Obsessive Compulsive Disorder

a.       Increased levels of norepinephrine increase memory and are associated with imprinting

b.      Imprinting

c.       Focused attention in humans is similar to imprinting and thus romantic attraction

d.   Concentration of Serotonin and Dopamine play a role in attraction

            Serotonin-Reuptake Inhibitors=↓ Obsessive-Compulsive Behavior

            ↓ levels of Serotonin= Romantic Love

            ↑ Dopamine= ↑ Excitation (Euphoria)

e.   Obsessive behavior comes from intrusive thinking

f.    Researchers have found that serotonin levels increase as time goes on in a relationship, therefore, a weakening of romantic emotions.  They estimate that passionate romantic love only lasts 9-18 months.


VII. The Evolution of Emotions

(1)   The attraction system evolved to conserve mating energy and facilitate mate choice in birds and mammals

(2)   During the course of hominid evolution, the three emotion circuits-lust, attractions and attachment became increasingly independent from one contributing to the modern pattern of marriage

(3)   The rejection of love evolved to produce adultery, divorce, and incidences of stalking, homicide, suicide, and clinical depression