Human Mate Choice Melissa Karson Psych 141 … From the Perspective of a Male Melissa Karson Psych 141

Key Questions What do males find attractive in females both short and long term? How do short and long term relationship preferences differ based on gender? Why is human mate choice important to males?

Human Behavior Based off chimpanzees and baboons Oestrus Share 98% genes with Chimps and possible common ancestor – both have males dominant over females, which have best priorities and most resources Gorillas share same ecological pressures as humans Oestrus – female’s sexual cycle when mating leads to fertilisation and is signalled via a swelling and reddening of the large external genitalia area – very noticeable! (they are ready to mate) -- leads to mate guarding (form consort relations with females in oestrus by following her and mating with her intermittenly during fertile period… means that male genes will be in offspring/ proliferate/ not someone else baby)

Closer Look at Oestrus What about humans? Cryptic Oestrus Human females do not have oestrus– often mistaken as a woman’s period/ menstruation cycle– however, do not see period or oestrus… so how do males know that females are ready to mate with? Cryptic oestrus – make men attractive to them even if not ovulating (will appear to be permanently in that state of oestrus) i.e. through swollen breasts Permanently swollen breasts during fertile years especially (false signals… dishonest oestrus.. And girls can get push up bras that fake their youthfullnes and ability to mate)

Fertile Window of Attraction Female facial attractiveness increases during the fertile phase of the menstrual cycle Follicular vs Luteal Phase Photgraph Study Visual cues to female ovulation do exist! Study: Digital photographs of 48 women (23 in UK and 25 in Czech Republic) in follicular (highest probability of conception 8-14 days into menstruation cycle) and luteal phase (17-25 days in cycle). Same location, same lighting conditions, same neutral facial expressions, performed test twice with digitally masked images (obscuring ears and hair) and with masked images (retaining those cues), men raters aged 19-44 yrs and females raters 18-33 years) Results: raters select follicular phases images as more attractive than luteal phase images, even with masked images, raters (both women and males) prefer follicular phase, people who had their pic taken also chose themselves as more attractive photo in their follicular phase Very easy to actually detect woman’s fertile condition, women are able to better discriminate subtle differences and that men might fail to detect some available cues to fertility, Enhanced attractiveness around ovulation lead to reproductive benefits for females in that they could enlarge the pool of potential mates or extra pair partners or could act more specifically as a fertility signal that is detectable only by long term partners

The Power of Smell Study on attraction: body odor (T-shirts) vs. picture Positive correlation between facial attractiveness and body odor Contraception in females Subjects wore a T–shirt for three consecutive nights under controlled conditions. Opposite–sex raters judged the odor of the T–shirts and another group evaluated portraits of the subjects for attractiveness. We measured seven bilateral traits of the subject's body to assess body asymmetry on a universal scale (measurements)…. Result: positive correlation between facial attractiveness and body odor (men who smelled tshirts rated the tshirts same as men who assessed the pictures), men could detect physical attraction most prominently in follicular stage (8-14 days into menstraution cycle – highest conception probability) Contraception: Common contraceptive, medroxyprogesterone acetate (MPA), on the olfactory cues of female ring-tailed lemurs (Lemur catta), and the behavioral response these cues generated in male conspecifics, MPA also changed a female's individual chemical ‘signature’, while minimizing her chemical distinctiveness relative to other contracepted females ( all had same smell and males could not tell which was most attractive based on smell alone), Lastly, males preferentially investigated the odorants of intact over contracepted females, clearly distinguishing those with immediate reproductive potential. (shows there is a way to tell smell as being attractive and for how woman will fake oestrus

Long Term Relationships Love Is “love” just a myth? Why do people try to change their physical appearance if love is rated as most important? Emotional stability Pleasing disposition Same for men and women Males and females both want love (highest to max scale of 3, males= 2.81 and females =2.87) Love: commitment, time, effort Physical attraction – people able to change/fake their true selves (i.e. straighten/curl hair, wear nicest clothes, wear color contacts, make up) but why should people change their appearance if love is what is rated highest.. Shouldn’t physical appearance not matter then? Kindness

Chastity More important to a male when looking for a female Long term mate selection Male Parental Investment (MPI) Chastity defined as resisting to have sex until marriage.. On Buss Study, chastity was low on list for both males and females… but even so there was a great difference for males than females Found more when looking for a long term mate not short term (possibility of having offspring and putting in effort and time into baby) Males score this as more important for a woman to be a virgin because it proves the baby is his (female can disguise their ovulatory signals and trick men into thinking that the baby is theirs to gain more male parental investment).. MPI is hard to find and if think can get it, the woman will trick man… Reduce possibility of cuckoldry (which is where the man is with a woman who is cheating on him)

Short Term Relationships Sperm Competition Cost-Benefit Ratio Men have less costs than females Men want their genes to proliferate Amount of sperm produced increases with size of testes, largest quantities of sperm most likely to inseminate females and pass on their genes (most sperm = most powerful.. Females want males with power) Less context dependant in casual preferences (do not have to reproduce and hold baby… females have one egg and need to go to best suitor who could potentially provide for their offspring and give male parental investment (MPI)

Physical Attraction Males rate physical attraction higher on priority list than females Universal definition of attraction Large eyes, good teeth, lustrous hair, full lips, small jaw, low waist to hip ratio (0.6), Symmetrical face and body 0.6 – ratio of circumference of waist to hips .. Compare to a coke bottle (attraction and youthfulness) Universal definition = youthful ness!! (men have it for awhile, but women start to not look youthful anymore – that is why see odd couple… women with older man for financial resources and men with female for youthful look More important in short term vs long term relationship (Buss study where rated… 0-3 0= unimportant and 3= indispensible … males score= 1.91, females score = 1.46 … high difference in scores between gender but low on Buss Scale (about half)) Good looks – better health, higher priority? (woman would place more emphasis on good looks where parasites are common because it would indicate good health) Relationship between signals of general fertility in women and what men find sexually attractive

Personal Advertisements Gender Typical Roles Females emphasize physical looks and youthfulness Have “flashier” photos as it is seen as “attractive” When seeking male, will mention the male should be career oriented Men emphasize status symbol, financial resources Rarely ever include age When seeking female, will mention physical attractions of a desired woman Example of Male Seeking Female: “She appears to be between 26 and 40 years old, but may appear younger than her age. She is at least 5'7" (I am 6'), she's either a blonde or a brunette … I can offer a reward of lifetime devotion … and am a partner that loves to cook and doesn't mind sharing in the household chores” One hundred fifty-one Internet personal advertisements were analyzed for attractiveness, income, mention of physical attributes, and mention of other positive personal characteristics. Results were generally consistent with predictions. In males, both wealth and attractiveness were related to decreased emphasis on other positive personal characteristics, while in women, emphasis on physical attributes (but not objectively rated physical attractiveness) was negatively related to emphasis on other positive personal characteristics.

Experiment on Casual Sex Clark and Hatfield Study Replications of BBC Study Is this a reliable study? Study: attractive men and female confederates walk around college campus, go up to stranger and ask them if they will have sex with them, 75% males say yes, 0% females say yes, males: compliment and an opportunity, produce offspring at a little cost, females: threat/ insult, more to loose Replicated recently with a BBC study.. Same concept, done in different culture (British culture), same results However, is this a reliable study? Reasons why not: culture taken into account? (also, not realistic for someone to just randomly come up to someone.. Not natural), age representative of entire population (college students are typically just experiencing first encounters with sex) male may be most desirous of sexual contact in his early years, while the responses of the females are still underdeveloped and while she is still struggling to free herself from the acquired inhibitions which prevent her from participating freely in the marital activity. But over the years most females become less inhibited and develop an interest in sexual relations, which they may maintain until they are in their fifties or even sixties, stereotypes of how supposed to act? (i.e. seen as wrong for a female to be seen as a whore, men gets more power in seeming like a pimp)

Coolidge Effect New = More Rat Study and Dopamine Lead Towards Polygyny, Polyandry, Infidelity, Divorce? Interest in new females, continue to copulate/produce more sperm for much longer than had he remained with same women (cross-cultural feature) Wont be able to produce as much sperm with same person (desire for sex decreases) As a rat copulates repeatedly with the same partner, less and less dopamine is released in the reward circuitry of its brain, dopamine – reward and pleasures, less dopamine = desire for new partner Humans are monogamous even with coolidge effect, porn = new mating opportunity (increase dopamine effect)

We Choose … Ourselves! Positive Assortative Mating Based on age, race, religion, ethnic background, physical location, physical characteristics, education Do opposites really attract? Buss study - -Positive Assortative mating (also sometimes called assortative narcissim)– we choose our mates based on similarity (pick mates who are more like us) Age- younger couples are more closer to age, 2nd marriages is where there will be seen more of an age gap Propinquity related to similar SES Physical characteristics – especially height The outcome of selection for positive assortment is to increase the genetic relatedness among family members, thus facilitating communication and altruism and increasing inclusive fitness without an additional reproductive effort

The End! Thank you!! Any Questions?