ANTH 216 Exam 2

Sex hormones (CAH, 2D:4D)

-CAH-girls have more masculine hormones. drugs for preventing. female sexuality affected by prenatal horomone signaling -butch lesbians have shorter index finger 2d:4d low 2d:4d shows high prenatal androgens 2d:4d decreases with fraternal birth order, homosexuality increases with birth order. high prenatal androgen leveles led to male homosexuality

What is sociosexuality? Explain the sex difference we see in sociosexuality

-a persons' willingness to engage in uncommitted sex/men are more willing to engage in it (less parental care required)

What predictions can we make about humans using sexual selection theory? (Are men or women more competitive for mates? Are men or women choosier about mates? Are men more or less choosy compared to most male mammals? Are females more or less competitive compared to most female mammals?)

-men are more competitive -women are choosier -men are less choosy compared to male mammals -females are more competitive than mammals

What are the potential costs of mixed reproductive strategies?

-men: their investment decreases w each child -women: you may not know who the father is/cheating

Genetics and Xq28

-monozygotic twins twice as likely male sexual orientation between 31 to 74 compared towomen 27-76concordant-sons shared alley dicordant dont share same allle Sex hormones-genetic variation affect hormonrd during birth -increased frequency of the Xg28 genetic marker in gay men. Homosexual brothers were 2x more likely to share Xq28.

What is inbreeding avoidance and the Westermark Effect? How do they relate to mutations and harmful recessive alleles?

-studies show that we have a learned sexual disinterest between people who are raised together (smell?) -Increased risk of harmful recessive alleles due to inbreeding (PKU allele)

Why are fluctuating asymmetry (FA) and sex hormone-dependent traits thought to reflect genetic quality?

FA: freedom from harmful mutations, ability to develop normally in the face of stressors............Sex Hormone-dependent traits: immune system activation, sex steroid production, indicate an efficient immune system

What do women gain from mixed reproductive strategies?

Get investment from long-term mate(s), good genes from extra-pair mate(s)

What is the Kinsey scale? Explain the different dimensions.

Kinsey scale is used to measure one's sexual orientation ranging from 0 (heterosexual) to 6 (homosexual).............it is based on four categories: self-identification, attraction, fantasy, and behavior [attraction & fantasy most stable]

What is MHC compatibility and why is smell relevant to MHC compatibility? Why is MHC compatibility relevant to the Red Queen Hypothesis?

Major histocompatibility complex (MHC).....MHC compatibility accounts for some differences in people's preferences for mates............Women prefer the smells of men with different alleles from their own.

What four hypotheses have been put forward to explain why genes associated with homosexuality have not been eliminated by natural selection? Explain each. Be familiar with evidence for each.

1) heterozygous advantage where heterosexual men with one copy of the gay gene have high fitness than those without. 2) maintained by kin selection. 3) sexual orientation is polygenic. 4) antagonistic pleiotropy

The perirhinal cortex and INAH-3

INAH-3: approx 2-3x large in heterosexual men as in women and homosexual men. INAH-3 appears to be related to sexual motivation, but it's not clear whether differences in the size or structure of this region directly result in sexual orientation.

What do men gain from mixed reproductive strategies?

Invest in one or more mates and mutual offspring, obtain extra-pair fertilizations opportunistically

What patterns of genital arousal do men and women exhibit?

BASED ON SAME-SEX SEXUAL STIMULI: men tend to only get aroused to their preferred sex while women tend to get aroused to every stimuli

What is the sex difference in the capacity for investment? What are the implications of this difference for men and women's mate preferences?

Both sexes expected to prefer investment. But sexes differ in how they can invest. Females can invest physiologically in offspring. Males can invest only "economically".

Maternal Immune Hypothesis and Y-Linked Neuroligin

"antimale"antibodies effect development of son. increases with more expose to every male. directly involved in brain development and T production.

How do men and women guard against mixed reproductive strategies?

Men: secure sexualy faithful in one mate, divorce partner and minimize investment........ Women: Attempt to make competitors less attractive to men by stressing the competitors' promiscuity

How does the Red Queen Hypothesis (parasite and host co-evolution) relate to the importance of physical attractiveness?

Physical attractiveness is reliable cue for fitness enhanced mates, symmetry/youthful appearance, evolved to view these signs of good health as attractive (low waist to hip ratio—fertility, bright eyes, shiny hair)

Fraternal Birth Order

The more older brothers a man has, the likelier he is to be homosexual. Homosexual men with older brothers are significantly smaller at birth than are heterosexual men with older brothers. This difference in birth, or some other consequence of differential fetal development, leads to homosexuality

What is gender?

behaviors that characterize males and females (usually socially)

What case involving sex reassignment at birth did we discuss in class? What do cases like this say about the blank slate view? What do they say about the effects of early development on later gender identity?

born Bruce, had botched circumcision, parents make him become Brenda, he rejected this and went back to Bruce.........debunks Blank Slate Theory, early development does not always affect gender identity

What are hormones and how do they work?

chemical messengers that are released into the bloodstream to stimulate specific cells or tissues into action

What psychological sex differences do we see in humans?

childhood play patterns, aggression, uncommitted sex preferences, etc

What is Congenital Adrenal Hyperplasia? How is it related to childhood toy preferences, childhood play patterns, and sexual orientation in women?

condition where instead of producing cortisol, it produces androgens (enzyme deviancy where you cannot produce cortisol, so it produces more androgens instead).......men aren't affected, women act more similar to men (aggression, play patterns, attracted to females)

What is the Lek Paradox? What are the two sources of continued genetic variation?

describes the paradox if women are always choosing the best genes every time, why aren't there only good genes left? ........ not always the case due to fluctuating selection pressures

What indicators of investment capacity in men do women prefer?

economic resources, high status, general good health

Heritability

estimates for sexual orientation are always ginifcantly lower than 1, male sexual orientation is heritable

In rats, what are male typical and female typical sexual behaviors? What hormone manipulations are necessary to change these behaviors?

females: lordosis (mounting behavior), males: mounting........you can switch these behaviors by treating sexes with the opposite sex's hormones (males would have lordosis, females would mount)

What gene on the Y chromosome leads to male development? What is the series of events that this gene sets in motion?

gene: SRY..........codes for testicular production (produces androgens)

What does the OSR look like in humans? Explain the relative parental investment and relative reproductive rates of men and women.

in humans, men reproduce quicker, so there are more men looking for mates; men are more competitive; women invest more into offspring/men invest economically

What are the three different types of reproductive strategies? Explain each.

investments (LT) genes (short term) mixed (both)

What is Adult Gender Identity Disorder?

medical term for being transgender (can be used for insurance reasons to get a sex change)

What are the Mullerian and Wolffian ducts and how do they develop?

men: Wolffian (develop into sperm ducts), women: Mullerian (develop into fallopian tubes)

What do the distributions of sexual orientation look like for men and women?

men: bimodal(few bi people)...........women: unimodal

What are the sex differences in minimal parental investment?

men: don't have to invest at all women: must go through at least 9 months of gestation and 18 months of lactation

What mating system characterizes humans?

monogomous

What are organizational and activational effects?

organizational: permanent changes affected by hormones (voice pitch) / activational: temporary (releasing cortisol when frightened)

What indicators of investment capacity in women do men prefer?

physical attractiveness, low WHR ratio, youth, fertility

What are gonads?

sex organs that produce gametes.....females (ovaries), males (testes)

What lines of evidence support the idea that women are more competitive mates compared to other female mammals?

sexually selected traits: body fat distribution, neonatenous features (feminine features)

What are effect sizes and Cohen's d, and why are they relevant for quantifying sex differences?

small (.2): smaller variance between men and women [more overlap], medium (.5), large (.8) [less overlap]

What lines of evidence support the idea that men are more competitive among themselves for mates than are women?

strength, aggression, same sex homicide (sexually selected traits)

What were the results of the Clark and Hatfield study?

study where questions of "would you go on a date with me/would you go back to my apartment with me/would you have sex with me" .......men almost always said yes to all three, where women rarely ever did (men are more interested in uncommitted sex)

Be familiar with gender nonconformity in the North American Indian alyha and in the Brazillian travesties.

third gender category, men who take on women-like roles............alyha imitate female actions and travesties incorporate female attributes through hormones and surgery

What is the difference between homosexual transsexualism and autogynephilia?

transsexualism: normal (male transitions into woman, attracted to men)............autogynephilia: men who get sexual arousal by thinking of themselves as females (usually where men who transition into women remain attracted to women)

What is Childhood Gender Nonconformity (CGN)? What behaviors characterize individuals with CGN? What is the relation between CGN and sexual orientation?

where a person doesn't really fit into their gender norms (tomboy), usually grow up to be homosexual

What is Complete Androgen Insensitivity Syndrome (CAIS)? How is it related to sexually differentiated psychological traits?

where you produce androgens but the receptors make you unable to use them (boys with these appear more phenotypically female)

Be familiar with the sexual behavior and sexual orientation of the Sambia of Papua New Guinea.

young boys preform felatio on older men in the tribe as initiation..........most boys remain straight but it does keep them out of the dating pool for a while so the older men can marry the younger women