Based on biology personality culture tradition Developmental Sexuality Sex vs Gender Sex o Biologically determined We hold a dichotomous view Gender o Psychological identity Biology Prenatal differentiation o Conception Zygote 23 pairs chromosomes 23rd pair sex chromosomes XX for females XY for males Variations in Biological Sex Klinefelter Syndrome o XXY extra X Symptoms not always shown 1 500 1000 males physical attributes lack hair broad shoulders develop breasts some feminine and some male characteristics taller and heavier than men higher risk for auto immune disorders breast cancer osteoporosis Low fertility Learning problems Reading and writing Turner Syndrome o X0 1 2000 2500 female births physical signs webbed neck puffy hands and feet no secondary sexual development no breasts very short 4 7 higher rate of hearing problems kidney and heart abnormalities non functioning ovaries sterile Learning disabilities Math and spatial intelligence Biology Prenatal Hormonal Influence rats o Organizing vs activating influences Organizing type of behaviors Activating frequency of behaviors o Feminization Masculinization behavior o De feminization De masculinization Decreasing tendencies Hormones and Sexual Differentiation Hormones lead to tendencies toward sex typical o Males embryonic testes produce androgens Testosterone male duct system inside Dihydrotestosterone DHT male external genitalia Antimullerian Hormone AMH prevents female duct system o Females female default system low androgens develop o Changing hormones changes behavior even biological sex is not neatly dichotomous Intersexuality Sexual anatomy neither completely male or female o XY with external female genitalia o XX with external male genitalia o Ambiguous genitalia Should we surgically correct ambiguous genitalia Strongly against cosmetic do not do surgery unless life threatening Hormonal Variations Androgen insensitivity syndrome o Complete AIS XY but insensitive to androgens Female external genitalia No duct system Usually raised as girls May be hyper feminized because of estrogen Tend to have Taller Athletic build Enlarged breasts Small amounts of hair under arm pubic Flawless completion No baldness Sterile Diagnosed and puberty of after Female gender identity Hines 2003 Compared to XX women No differences personality and behaviors o Partial AIS Some sensitivity to androgens Less sensitive more AIS symptoms Ambiguous genitalia at birth Congenital Adrenal Hyperplasia o Too much androgen prior to birth and throughout life o In boys Not very many signs at birth May appear to enter puberty early No differences in gender typed behavior o In girls features Masculinized external genitalia some male like May experience developmental male features and disruption of menstruation at puberty Early research Sex atypical behaviors Reject stereotypical female roles Orientation Recent studies Higher rate of bisexuality lesbianism More likely to be transgender Other effects of hormone exposure o Androgen exposure and sexual orientation Finger length ratio Men Second finger shorter Women Same or second finger longer Androgen marker Lesbians More male typical butch even more Penis size Diethylstilbestrol DES exposure Gay men have slightly larger penis o Synthesized estrogen given to pregnant women o DES converts to testosterone Masculinizing effect on fetus o Female fetus More likely to be bisexual or gay Genital development typical Later outcome are atypical Other Brother Effect o Youngest brother has the highest chance to be gay o Woman produces a chemical reaction to Y chromosomes in the mother for first boy increases overtime in subsequent males Conclusions orientation orientation o Strong biological influence on gender identity and o Some genetic influence on gender identity and