284 terms

Psych 146 Final

Last psych test before I complete my major!
the period of highest sexual receptivity (or "heat") in some female mammals that coincides with the time of egg release by the ovary
females' attractiveness to males
increases during estrous
females' sexual preferences during estrous
males with putative fitness indicators (e.g. normal T male > castrated male)
hormone that regulates effects during estrous
immature eggs in ovarian follicles
rate of small follicle development
~1000/month (beginning prenatally)
follicle stimulating hormone
follicles die in absence of
FSH and LH signals
number of small follicles at birth
~1 million
number of small follicles at puberty
~.5 million
number of small follicles at menopause
if developing follicles receive FSH and LH signals
they develop further into a "dominant follicle"
support cells around "dominant follicle"
increase and produce estrogen
dominant follicle
follicle that is selected to mature and ovulate in the next cycle
estrogen primes
LH surge that triggers ovulation
birth control pills block
FSH or LH surge
blocking FSH
follicles die instead of developing
blocking LH surge
prevents ovulation
process of releasing FSH, LH
hypothalamus releases GnRH → pituitary (LH, FSH)
estrogen casuses development of
uterine lining in preparation for possible implantation of zygote
follicle after ovulation
turns into corpus luteum
corpus luteum
endocrine tissue which produces hormones, estrogen, and progesterone which prepares the uterine lining for receiving an embryo
phases of cycle
1. follicular phase
2. luteal phase
3. "fertile window"
follicular phase
extends from the beginning of menstration (day 1) until ovulation (day 14)
luteal phase
extends from day 15 (just after ovulation) to day 28 (onset of menstration); conception not possible during this phase
"fertile window"
days when conception is possible: day of ovulation and up to 5 days before
sexual receptivity in human females
not confined only to fertile window; physically possible to copulate any time
some evidence that female libido influenced by
cycle phase
reasons that the correlation between female libido and cycle phase is hard to study
1. using sexual thoughts as DV assumes that output of mechanism is actual thought

2. studying sexual activity is problematic because males and females initiate sexual contact and it confounds with female attractiveness and male interest
there is decent evidence that libido near ovulation is
Wallen (2001)
more sex initiated during "fertile window"
Roberts et al. (2004)
took photos of SAME women during late follicular phase (~day 12) and in luteal phase (~day 22)

raters chose which photo of pair was more attractive
Roberts et al. (2004) results
depending on masking conditions (obscure hairstyles or not) and rater sex, follicular chosen as more attractive ~54-58% of the time (significantly greater than chance)
Miller et al. (2007)
asked strippers to record their periods and also their tipi earnings from lap dances over a 60 day span

18 women, 7 on pill and 11 not on pill

responded on website, w/ 16.4 entries on average (out of 60 requested)
Miller et al. (2007) results
women not on pill showed spike in earnings mid-cycle
cue that drives Miller et al. (2007) stripper results
uncertain (could be odor cues, shifts in behavioral patterns, subtle morphological changes [body shape, face attractiveness])
there is evidence that women's odors near ovulation are judged as
more pleasant/sexy
there is evidence that women's attracitvenss near ovulation
inceases, but the effects are smaller than in many non-human species (more subtle "estrous" in humans)
female preference if in the fertile window
focus on potential indicators of genetic quality more so than at other times within cycle
female preference if not in the fertile window
focus more strongly on direct benefits
mixed strategy of female mate preference
choose feminine, high investing men as long-term partners; cheat with masculine, high testosterone men when fertile to get good genes
selection for extra-pair copulations
because women obtain benefits only when fertile, but could pay the cost throughout the cycle, selection may have shaped female interest in men who possess indicator traits of good genes such that it changes across the cycle
if androgens indicate genetic quality
then the whole suite of traits affected by T may be preferred within the fertile window
greater testosterone
lower FA, facial masculinity/symmetry, muscularity, behavioral displays, odors, deeper voice pitch
Gangestad & Thornhill (1998)
tested effects of cycle phase on preferences for odors of symmetrical men

men wear clean T-shirt to bed for 2 nights whille attempting to stay odor-neutral

women raters sniff shirts on morning after second night and rate for pleasantness, sexiness, and intensity

women's "conception risk" estimated
Gangestad & Thornhill (1998) results
women near fertile window show preferences for odors of more symmetrical men (low FA)
sensory modality singled out by women as that which most affects their sexual responsivity and mate choice
higher correlation in Gangestad & Thornhill (1998) odor study
greater preference for symmetry
voice pitch generally found more attractive in men by women
low pitch
preference for artificially lowered voice pitches becomes greater when
women are tested near ovulation (Feinberg et al, 2006)
Gangestad et al. (2004)
videotaped men being "interviewed" by an attractive woman for a possible lunch date; a male competitor was interviewed at the same time and his responses visible on a video monitor

women watched 1-min. clips of these men and rated them for both long and short-term attractiveness
men with low body FA in Gangestad et al. (2004)
used more direct and competitive strategies: asserted superiority, derogated competitor, etc. 9vs. asserting he was nice guy, etc.) and had greater "social presence" (less nervous, direct eye contact, etc.)
Gangestad et al. (2004) results
preference for masculine behavioral displays increased right before ovulation
evidence for EPC argument
very strong
if women are seeking good genes near ovulation
they may present themselves more attractively near ovulation
Haselton et al. (2007)
women brought into lab twice: once within fertile window (high fertility) and once in luteal phase (low fertility)

from view photographs taken

judges rated in which of two photos woman was trying to "look more attractive"
Haselton et al. (2007) results
judges chose high fertility photo 59% of the time
evidence exists for cycle phase effects on
1. sexual receptivity
2. attractiveneess
3. self-presentation
4. preferences for testosterone-dependent traits in men
homologies with estrous-cycle effects in nonhuman species are difficult to explain via
traditional socialization-based accounts of human psychology
alternative explanation to EPC model
there are none; it is an inference to the best explanation

"...it is difficult to understand the nature of these preferences otherwise." - Gangestad (2000)
Within-Cycle (EPC) Position
shifts in mate preferences are designed to change behavior WITHIN a given cycle

point is to pursue mixed mating strategy
Between-Cycle Position
evolved mechanisms are designed to produce shifts in mating psychology BETWEEN different cycles

holds that female mate preferences designed to shift over long periods of time
according to within-cycle position, brain mechanisms read hormonal signals to answer the question
Am I currently within the fertile window?
according to between-cycle position, brain mechanisms read hormonal signals to answer the question
Am I currently in a fertile cycle?
mating mechanisms in less fertile cycles
lower libido/preference for fitness indicators
mating mechanisms in more fertile cycles
higher libido/preference for fitness indicators
low estrogen/progesterone
lactation, food shortage, high energy expenditure, illness/stress
high estrogen/progesterone
no lactation, sufficient food, moderate energy flux, healthy/low stress
it makes functional sense to think about men's genetic quality
across the cycle (NOT just during fertile window) during high fertility cycles
between-cycle logic
turn on mating psychology during times of likely fertility
why no keep mating psychology turned on all the time?
there are other adaptive problems to address
attraction to stimuli has
motivation functions that affect behavior
example of motivational functions of stimuli
motivation to pursue food and eat when hungry and food is attractive
EPC position predicts
tight coupling to fertile window
Between-cycle predicts
high estrogen times > low estrogen even outside fertile window

*preference curves should mimic estrogen curves
more fertile cycles have
more follicular estradiol
follicular E predicts
luteal E
Roney & Simmons (2008) Paper
tests hypothesis that preference curves should mimic estrogen curves using faces as dependent measure
limitations of past faces studies
artificial faces, no T measures, no evidence regarding the physiological mechanisms that may regulate cycle phase shifts in women perceivers
Roney & Simmons (2008) hypothesis
estradiol concentrations will predict preferences for higher testosterone faces
Roney & Simmons (2008) method
39 heterosexual men from UCSB (18-24 yrs.)

digital photos at a standard distance with a neutral expression

saliva samples collected to assay testosterone
Roney & Simmons (2008) ratings of face photographs
75 women from UCSB, none on hormonal contraceptives, statistics on cycle recorded

viewed photos in random order on PC at self-paced rated, rated photos for physical attractiveness
Roney & Simmons (2008) results
women show stronger preferences for masculine/high T traits in men during high vs. low estrogen times in the cycle
testosterone preference in women
increases with estradiol levels (r = 0.52, p = 0.002)
within vs. between-cycles debate
not clear whether it is one, the other, or combination of the two
hormones (FSH and LH) that stimulate the development of ovaries and testes
leydig cells
cell that produces testosterone and other androgens and is located between the seminiferous tubules of the testes
male sex hormone process
hypothalamus releases GnRH → anterior pituitary (LH, FSH) → testes → testosterone
organizational (developmental) effects of testosterone/androgens
produce relatively irreversible effects on body and brain (e.g. sex-differentiation of genitalia) and possible early effects on brain organization
activational effects of testosterone/androgens
more temporary and reversible effects (e.g. many secondary sex traits in nonhuman species that atrophy when T is withdrawn like antlers during nonbreeding season)
organizational effect in schematic model of specialized mechanisms
affects the "developmental program" (early sex hormone exposure)
activational effects in schematic model of specialized mechanisms
affects the "cognitive program" through T input
Case-study (Diamond, 1997) demonstrates
organizational effects of early androgen exposure despite minimal activational exposure to androgens and gender role socialization intended to produce opposite effects
Case-study (Diamond, 1997)
"John" reassigned to be female at 8 months, still displayed male behavior and rebelled at living as a girl at age 14
5-α Reductase Deficiency
deficiency in enzyme that converts T to dihydrotestosterone (DHT)
dihydrotestosterone (DHT)
androgen required in high levels for masculinization of genitals
5αRD effects on body
genitals appear female at birth, but produce large amounts of T at puberty, which overcomes deficiency and genitals masculinize along with development of typical secondary sex traits
5αRD in Dominican Republic (Imperato-McGinley et al., 1979)
socialized (strongly) as females, but most quickly switched to male identity and sexual preferences
5αRD in Dominican Republic (Imperato-McGinley et al., 1979) findings
provides evidence that socialization alone does not explain gender identity and that T acts in wiring up brain mechanisms (without needing to be converted to DHT)
general theory of testosterone
testosterone promotes physiological and behavioral processes related to mating effort and directs energy away from competing processes related to survival effort
hormone analogy
hormones are like a radio broadcast to the entire body, received by any cells that tune to the right frequency
hormones can reach
any calls that express receptors for them
muscle cells express
T receptors
skeletal muscle mass increases under
T exposure
Bhasin et al. (2001) T manipulation study
gave 61 men a drug that blocked GnRH production (eliminating natural T) and assigned them to T injections at does between 25 mg and 600 mg
Bhasin et al. (2001) T manipulation results
gains in fat-free mass and leg strength occurred with higher doses
testosterone promotes
fat catabolism as source of energy
breakdown of more complex substances into simpler ones with release of energy
Luteinizing hormone
(LH) a gonadotropic hormone that is secreted by the anterior pituitary
Yesilova et al. (2000) study
studied young men with hypogonadism and measured various antibody counts before and after treatment with synthetic LH
Yesilova et al. (2000) results
testosterone increased and antibody counts dropped 20%-40% after treatment
testosterone suppression of immune responses
modulated by energy availability (males with large energy budgets can afford both higher T and larger immune responses)
example of T suppression modulation
T injections reduce immune responses to a pathogen in male zebra finches, but leptin injections reverse the suppressive effects
behavioral effects of T in paternatlly investing birds
1. reduce offspring provisioning
2. increase aggressiveness toward other males and attempts at territory expansion
3. increase pursuit of extra-pair females
correlational evidence for effects of T in humans
1. greater status-seeking
2. greater dominance
3. greater aggressiveness (small effect)
4. greater sensation-seeking
5. greater risk-taking (financial measures)
6. greater extraversion
hockey players with greater penalty minutes
have higher T
general effects of T
directs energy for muscle mass, decreases immune response/fat breakdown, increased behavioral aggressiveness/competitiveness
Muehlebein et al. (2005) malaria quasi-experiment
8 male, 9 female Honduran villagers infected with malaria compared to healthy matched controls, assessed T during diagnosis and treatment
Muehlebein et al. (2005) results
T increased after treatment
T levels in seasonally breeding species
drops to castrate levels in non-breeding season (not want to pay costs of higher T if there are no current mating benefits
circumstances when mate-seeking is less important in humans
1. no females are around
2. male already has a partner/in a relationship
3. male has kids, paternal investment more important
Anonymous (1970) beard study
researcher isolated himself on a remote island and recorded his beard growth (androgen-dependent) during periods of isolation, and also when he visited girlfriend on mainland or she visited island, weighed beard shavings each day
Anonymous (1970) results
beard shavings decreased in isolation
Grey et al. (2002)
collected saliva samples from Boston-area men to measure T (29 unmarried, 14 married w/o children, 15 married w/ children), hypothesized lower testosterone in married men and fathers, to avoid costs of T and promote paternal care
Grey et al. (2002) results
lower T in married, even lower T w/ children (not necessarily causal though)
immune challenges, food shortages, stress
lowers T
mate-seeking/female presence
raises T
courtship responses
how many nonhuman males respond to females or cues from females
cognitive program for vertebrate courtship
cues from females → activation of limbic-hypothalamic structures (GnRH, LH, T) → courtship behaviors (immediate), T increase (post 15-20 min)
immediate result of activation of limbic-hypothalamic structures
courtship behaviors
t increase in activation of limbic-hypothalamic structures happens
post 15-20 minutes
limbic-hypothatlamic transducing pathway
chemosensory → VNO → AOB → amygdala → medial preoptic area (mPOA) → limbic-hypothalamic structures → V/I/T structure feedback
lesions to medial preoptic area (mPOA)
abolish copulation, reduce courtship, eliminate T response
sex steroids (T, E) regulate
signaling properties of neurons within structures of the transducing pathway
Visual/Auditory/Tactile transducing structures
amygdala, mPOA, hypothalamus
Oomura et al. (1988)
electrodes placed in mPOA of male macacques recording cell activity
Oomura et al. (1988) results
firing increases when shutter opened to reveal female and fires rapidly as male approaches female; decrease during intromission but then increases again just before next bout of intromission; firing stops after ejaculation; firing increases again as refractory period ends (~10 min.), when male will again press lever to access female
T injection into mPOA after castration
can restore courtship behaviors to normal levels
castration effects
same as lesions to medial preoptic area (mPOA)
T production decreased by
stress/illness, seasonal cues, subordinate status, presence of offspring
exposure to erotic or sexually explicit films causes
increased LH or T levels in men within 10-20 minutes
Roney et al. (2003)
male subjects randomly assigned to a 5-minute conversation with a male or female confederate, saliva samples were taken before and 15 minutes after interaction, confederates rated the subjects' behavior during the interaction
Roney et al. (2003) results
significant increase in T when paired with female confederate, increase in display behaviors (reported by confederate)
Roney et al. (2003) changes in T by courtship-like behaviors
higher T change, more courtship-like behaviors (female condition), no correlation for male condition
limitations of Roney et al. (2003) study
small sample size, University of Chicago students are "unusual" (little exposure to scantily clad, attractive women; introverted, neurotic, chain-smoking, nerdish, female-deprived, quasi-autistic, etc.)
Roney, Lukaszewski, & Simmons (2007)
same design as 2003 experiment, but done at UCSB
Roney, Lukaszewski, & Simmons (2007) results
T increased relative to baseline; in response to men, no change observed

T correlated with experimenter-rated measures of extraversion and self-disclosure in female condition, but not male condition
effect of cortisol on T
can inhibit its production
baseline cortisol elevated during
food shortage, illness, social stress (conditions in which courtship may be maladaptive)
Roney et al (2010)
men's baseline cortisol negatively correlated with size of T responses to conversation with women
functions of transient T elevations
T spike that quickly returns to baseline may not do much to re-distribute energy (too fast to change muscle mass, immune function)

spikes have informational value to brain mechanisms (signal adjustment in risk-taking, motivation, competitiveness linked to courtship effort)
Aikey et al. (2002)
used a maze with open and closed arms to measure risk-taking in male mice (rodents prefer dark, covered spaces; time in open arms a measure of boldness); male mice randomly assigned to be exposed to water or female urine
Aikey et al. (2002) results
males went into the open more often with urine condition (more risk-taking)
possible reason for rapid T increases in humans
may have quickly promoted willingness to compete for new mating opportunities when meeting young, interested woman in ancestral environments
Sociosexual Orientation (SOI)
the tendency to prefer either unrestricted sex (without the necessity of love) or restricted sex (in the context of a long-term, loving relationship)
sociosexual orientation measured in
low SOI people
(restricted sociosexual orientation) demand commitment and closeness in a relationship before engaging in sex
high SOI people
(unrestricted sociosexual orientation) comfortable engaging in sex with less commitment or closeness
higher SOI people self-report
1. having sex earlier after relationship initiation
2. more likely to have had sex with another person while dating current partner
3. lower commitment to relationships (this does not seem to be lost on their partners
discriminant validity
examines the extent to which scores on the measure are not related to scores that measure some other unrelated construct
discriminant validity of SOI
SOI does not seem to index general sex drive or libido
Simpson & Gangestad (1991) SOI correlation
no correlation between SOI scores and frequency of sex in last month for couples in sexual relationship
between-sex differences in SOI
men (on average) have higher scores than women (expected from PI theory)
within-sex differences in SOI
tends to be greater than between-sex variance
SOI attitude items
female < male
SOI behavior items
no noticeable difference
possible causes of within-sex individual differences
1. context-sensitive mechanisms designed to produce different outputs depending on current circumstances (based on own attractiveness, resources, etc.)

2. different mechanisms develop depending on exposure to different environmental inputs

3. developmental noise, accidents

4. heritable differences
example of developmental noise or accidents
greater exposure to prenatal androgens
hypothesis of within-sex individual differences in men
context-sensitive mechanisms lead to different mating strategies
Gangestad & Simpson (2000) SOI in men proposition
less sexually attractive men (lacking cues to good genes) will be rejected as short-term mates more often, so high SOI strategy does not pay for them

vice versa with more sexually attractive men
Gangestad & Simpson (2000) SOI in men hypothesis
brain mechanisms that encourage high vs. low SOI strategies are turned on or off depending on feedback men receive regarding own attractiveness
evidence for Gangestad & Simpson (2000) position
men with low FA seem to adopt more short-term strategy (targeted differentially by women in fertile window)
Evidence for success of low FA men relative to high FA men
1. greater lifetime # of sex partners
2. self-report more extra-pair partners and being chosen more often as extra-pair partners
3. FA (-) correlates significantly with SOI scores (r= -.20 across a few studies)
cost-benefit critique of Gangestad & Simpson (2000) position
in modern environments, oversupply of fertile young women (cities, single bars, IV), in ancestral environments, # of fertile young women may have been extremely limited & even very attractive men would be limited in # of insemination opportunities
expected estrogen in hunter gatherer populations
men playing pure short-term strategy limited by rarity of fertile cycles in small group environments
cost-benefit critique conclusion
expect men to be designed primarily for long-term mating with psychology of opportunistic copulations on the side
low SOI men and opportunistic mating
"go to bed with me tonight" study suggests that even low SOI men must be more open to opportunistic sex than most "high" SOI women
Roney's conclusions on men and SOI
men don't have 2 sets of mechanisms that are conditionally activated (LTM, STM), but are primarily designed for LTM, but have mechanisms that motivate interest in opportunistic copulations
Roney on within-sex SOI differences in men
differences exist in part because some have more opportunistic copulation opportunities than others, but not playing fundamentally different strategies
Gangestad and Simpson (2000) types of benefits women seek in men
direct benefits (food, shelter, protection, care of offspring)
indirect benefits (good genes)
may be trade-offs in men's likelihood of providing each
high SOI women argued to prioritize
good genes
high SOI women self-report
physical attractiveness more important to them than low SOI women
high SOI women rated symmetrical men as
more attractive than did low SOI women
good genes may be more important to women if
they have other sources of direct benefits
evidence that women may prioritize good genes vs. direct benefits if they have other sources of direct benefits
poor since wealthier women show stronger preferences for men's resources
hypotheses of within-sex individual differences in women
different mechanisms develop different cognitive programs, one that demands commitment before sex and another that does not
Belsky et al. (1991) developmental theory
Human mating systems vary and a child's early environment may provide clues regarding the type of system they are growing up in (father present, conflict at home, etc.). If they receive clues that they are growing up in a system with unstable pair-bonds, then implement a developmental program that promotes early and fast rate of reproduction (waiting for committed relationships wastes time when they are unlikely to arrive).
Belsky et al. (1991) developmental theory consequences of unstable upbringing
earlier puberty, more unrestricted sexuality (high SOI)
Belsky et al. (1991) developmental theory flow chart
A. family context → B. childbearing → C. psychological/behavioral development → D. somatic development → E. reproductive strategy
two pathways that ultimately influence mating strategy in girls
Type I - stable
Type II - unstable
three types of stress in developmental theory
1. nutritional/resource stress
2. socioemotional stress
3. father absence
nutritional or energetic stress
consistently related to DELAYED puberty
lower fat reserves, higher WHR, high energy expenditure (e.g., female athletes) associated with delayed puberty
socioemotional stress
family conflict, fighting, lack of parental warmth and support
retrospective studies (people recall level of conflict as adults) on socioemotional stress
tend to find more stress associated with earlier puberty
prospective studies (observe families in childhood, come back years later to measure pubertal development) on socioemotional stress
generally find little evidence that it leads to later puberty
father absence
associated with earlier puberty, more distant relationship with father than when present
early puberty predicts
early onset of sexual activity
pubertal timing, SOI or # of partners
most studies find no relationship between them
Hoier (2003) development and reproductive strategy findings
no correlation between onset of puberty and SOI, sex partners/year, or preferences for attractiveness
lowest SOI reported in Hoier (2003)
one stepfather after separation from biological father, or both biological parents present
Hoier (2003) correlation between onset of puberty and number of desired partners
early onset linked to more desired partners over lifetime
stress type with strongest evidence of effect on earlier pubertal development
father absence
early puberty alone
does not seem to predict SOI or # of partners
the proportion of variation among individuals that we can attribute to genes
heritability of universal traits
close to 0
(heritability indexes genetics with respect to individual differences)
evolutionary psychology tends to study
design universal mechanisms with low heritability
phenotype is a product of
genetic and environmental influences
twin studies on female SOI and pubertal timing
suggest at least 1/2 of the variance in pubertal timing can be explained by genetics and SOI scores have substantial heritability
androgen receptor (AR) gene
encodes for the androgen receptor
androgen receptor
T binds to it and it then binds to DNA, allowing T to turn on/off whole suites of other genes and produces sex differences during development
AR gene is highly
poylmorphic (many different versions of the gene exist in the population), CAG repeats between 9-31 times in code depending on person
long # of CAG repeats in AR gene
less active receptors
short # of CAG repeats in AR gene
more active receptors (greater risk of prostate cancer, higher rates of sperm production, higher rates of violent crime)
Androgen receptor gene predict variance in mating psychology?
might predict men with shorter repeats will be more responsive to potential mates, have more sensitized pathway structures that lead to greater hormonal responses to females
Roney et al. (2010) AR receptor study
exposed men to either a flirtatious woman experimenter or a friendly male experimenter and took saliva samples before and 40 min. after interactions and cheek cells
Roney et al. (2010) AR receptor study hypothesis
shorter CAG repeats will predict larger T increases among men in female condition
Roney et al. (2010) AR receptor study results
shorter CAG repeats predicted larger T increases among men in female condition
summary for AR receptor gene
shorter repeats may predict greater physiological and behavioral investment in mating effort (larger T responses to women, greater phsyical strength, greater dominance, higher rates of sperm production)
chemicals produced by one organism that is capable of altering the reproductive behavior, psychology or physiology of another member of the same species
McClintock (1971) women living together study
after spending a lot of time together, there is a significant decrease in the difference between period onset dates between women
McClintock (1971) women living together assumption
synchronizing mechanism is a pheromone
critics of menstrual synchony argument
about 1/2 of women are likely to exhibit some synchrony by chance alone
female signaling of estrous in nonhuman species
explicit (odors, sexual swellings)
Singh & Bronstad (2001) human estrous argument
it would be adaptive for men to be able to detect timing of ovulation via women's odors
Singh & Bronstad (2001) female odor study
women wore t-shirts to bed during fertile window and during luteal phase, men sniffed t-shirts and rated for intensity, pleasantness, and sexiness
Singh & Bronstad (2001) female odor results
t-shirts worn during follicular phase rated more pleasant and sexy and were rated higher on average than luteal t-shirts
Havlicek et al. (2006) female odor study
between-women variation in odor attractiveness is consistently greater than within-cycle variation across studies
explanations for attractiveness of follicular odors
1. estrogen is higher in more fertile cycles

2. men could track odor cues of estrogen to identify when own partner or other women experiencing fertile cycles

3. may see small within-cycle shifts because estrogen is also highest near ovulation in cycle
2 functions for tracking estrogen
1. mate choice
2. mate guarding across more fertile cycles
if odor attractiveness is couple to estrogen
odor attractiveness may not be a good predictor of fertile window
bad explanation for attractiveness of follicular odors
men target STM mating effort toward women in fertile window (unlikely because between-women variance > within-cycle variance)
female attractiveness in nonhuman species
facilitated by estrogen
pheromonal explanation for Miller et al (2007) stripper study
men give tips because of response to odor and estrogen
Roney's human pheromone proposal
mechanism makes higher estrogen smell better (used to index when women are fertile vs. infertile cycles)
Savic et al. (2005) PET scan study
heterosexual men and women and gay men smell AND (derived from T and found in men's sweat), EST (odor similar to that produced by women when E is high), control odors and plain air and run brain scans on participants while smelling
Savic et al. (2005) PET scan results
gay men responded like straight women to steroid odors and unlike straight men
T injections in nonhuman species
improve odor attractiveness of males in some nonhuman speices
Ferkin et al. (1994) meadow mice study
castrated male meadow mice and then injected them with different doses of T, rubbed them on glass slides and put slides in female's cage
Ferkin et al. (1994) meadow mice study results
female investigated scent of higher T males for longer
Rantala et al. (2006) theater study
men wore t-shirts while watching movies for 5 hours; t-shirts rated by women tested at any phase of cycle
Rantala et al. (2006) theater study results
men's T not correlated with women's ratings of T-shirts
found in men's sweat and possibly evidenced to cause activation of hypothalamic nuclei in women's brains
pheromones from men
there is some evidence that women may detect androgen-dependent pheromones from men
Saxton et al. (2008) speed dating studies
women randomly assigned to have (1) AND in clove oil, (2) clove oil only, or (3) water to upper lip while speed dating; experimenter tested whether the same men rated more attractive by women exposed to AND vs. to other odors
Saxton et al. (2008) speed dating results
AND condition only significantly higher than others in first study
AND-related conclusions
T-derived compounds in AND may act as chemosignals and produce sex-specific brain activations in hypothalamic nuclei and increase ratings of men's attractiveness, but no evidence that natural variations in AND production affect women's judgments of men
major histocompatibility complex (HMC) genes
encode for proteins that recognize foreign antigens
immune system compatibility and pheromones
mice prefer odors of MHC dis-similar individuals as mates to:
(1) avoid inbreeding
(2) diversify immune system genes
Wedekind et al (1995) MHC-dependent odor preference study
took blood samples to determine MHC genes of participants; men more t-shirts to bed for 2 nights and women sniffed shirts to rate for pleasantness, sexiness, intensity
Wedekind et al (1995) MHC-dependent odor preference results
some evidence that women find odors of MHC-different men more attractive
MHC similar couples
longer time to get pregnant, longer birth spacing if no birth control used
MHC implications
there is a potential cost to the use of hormonal contraception during the process of mate choice since in blocks choosing mechanisms
Buss et. al jealousy prediction about men
should be more upset by sexual vs. emotional infidelity
Buss et. al jealousy prediction about women
should be more upset by emotional vs. sexual infidelity
Buss et al. (1992) "What would upset you more?"
men far more distressed by sexual infidelity
"double-shot" hypothesis
emotional infidelity in men also predicts sexual infidelity, while sexual infidelity in women also predicts emotional infidelity, which is why one infidelity type is chosen as more disturbing
"double-shot" conclusion
men and women do not have distinct jealousy mechanisms, the simply have different beliefs about predictors of double-shot
response to double-shot critique
if you specify clearly that a double-shot or single-shot has occurred, should see no sex differences in judgments of whether sexual or emotional infidelity is more disturbing
Buss et al. (1999) double-shot study
gave participants scenarios in which both types of infidelity occurred and asked which is more troubling
Buss et al. (1999) double-shot results
men more troubled by sexual infidelity even when stated specifically that double-shot or only single shot has occurred
physiological effects of jealousy
men show greater physiological reaction to sexual vs. emotional infidelity; woman vice versa
Harris (2000) physiological effects of jealousy results
physiological responses were just as strong for imagining self have intercourse as for imagining partner's sexual infidelity
Harris (2000) physiological effects of jealousy implications
no evolutionary explanation for sex difference in physiological responses to jealousy
cognitive description of jealousy
Baker and Bellis (1989) ejaculate adjustment study
couples asked to collect semen in condoms from both acts of intercourse and masturbation
Baker and Bellis (1989) ejaculate adjustment hypothesis
longer couple has been apart, more sperm will be found in copulatory ejaculate
Baker and Bellis (1989) ejaculate adjustment results
sperm in copulatory ejaculate decreases the longer the couple is together since last copulation
symptoms of romantic love
1. obsessive thinking about target/intrusive thoughts
2. idealization of partner
3. involuntary physical symptoms (giddy smiling, trembling, heart rate)
4. euphoria/elation vs. depression
frequency of full-blown romantic love syndrome
relatively rare (<5 times per lifetime)
"mate value" (MV)
someone's effective market value as a romantic partner, operationalized as the proportion of others who would accept them as a romantic partner
MV is a function of cues to:
1. fertility
2. parenting ability (direct benefits)
3. good genes (indirect benefits)
media's negative effect on mating psychology
possibly affects the construction of mate value curves
should stop searching for partner when
benefits of current partner > (benefits of better partner - costs of searching for a better partner)
commitment problem
arises when it is in a person's interest to make a binding commitment to behave in a way that will later seem contrary to self-interest
commitment problem in mating context
man pursuing STM strategy could signal desire for LTM, but then abandon woman once he obtained sex; men really seeking LTM face problem of signaling commitment when they could be faking
Frank (1988) argument
love can function as solution to commitment problem
love as solution to commitment problem
desire to be with other person based on "love" for and idealization of that specific partner vs. rational calculation of costs and benefits of relationship
love as behavioral regulator
emotional device that implements long-term interests over short-term benefits of infidelity
irrationality of desires in love
if reasons for attraction are too rational, suggests person is replaceable
humor as signal
involuntary laughter may send hard to fake signal that parties like each other
why love is difficult to fake
1. love can make you look foolish
2. love signals similar to submission signals
3. attractiveness of someone who signals "in love" too soon plummets
4. behavioral confirmation (time commitment, etc.)
5. other costs (engagement rings, etc.)
courtship process
1. signal attractiveness, mate value, dominance, better than others
2. signal commitment to specific individual
cognitive description of love
"love" provides
insurances against abandonment that allows mutually beneficial partnership for producing offspring