ANT2301 Test 2 Study Guide:• with concealed ovulation:⁃ decrease in sexual dimorphism⁃ (decreased direct male-male competition)⁃ increased reliance on male provisioning⁃ increase in pair-bonding between males and females (long-term)• male preferences- expectations:⁃ due to inequalities in investment, females face several adaptive problems in finding the right mate⁃ infer that females and males evolved preferences (information processing biases) that enable them to assess traits that indicate fitness levels⁃ INCREASE REPRODUCTIVE SUCCESS⁃ What traits are correlated with high mate value?⁃ evolutionary explanations⁃ social psychology explanations• Biological traits:⁃ 1) personality based on perceived facial features and length of relationship⁃ 2) preferential changes in preferred odor⁃ MHC-major histocompatibility complex⁃ male preferences⁃ 3) the age factor⁃ male preferences vs. female preferences• Facial preferences:⁃ Penton-Voak et al., (1999): found that females preferred masculine looking faces at ovulation, but less-masculine faces when non-fertile⁃ however, females using oral contraception reveled no cyclical change in facial preference⁃ females did have no overall preference for symmetry but this was irrespective of menstrual cycle phase⁃ overall, females prefer a more feminized face during luteal phase⁃ may indicate increased parental care (lower testosterone levels)⁃ levels are correlated to parental care⁃ short-term/high risk & more masculine faces preferred• menstrual cycle phase and face preferences:⁃ preferences:⁃ masculine (good genes) men around ovulation⁃ feminine (Caring sharing) men at other times⁃ similar patterns of change during the menstrual cycle have been observed for voice preferences⁃ changes in women's preferences for masculinity reflects change in progesterone level rather than change in estrogen level• major histocompatibility complex:⁃ MHC genes make the molecules that enable the immune system to recognize invaders⁃ the more diverse the MHC genes of the parents, the stronger the immune system of the offspring (not too foreign)⁃ Claus Wedekind experiment (1995 ): a group of female college students smelled t-shirts that had been worn by male students for two nights without deodorant, cologne, or scented soaps⁃ an overwhelming number of women preferred the odors of men with dissimilar MHCs to their own⁃ however, their preference disappeared if they were taking oral contraceptives⁃ • olfactory genetics: ⁃ body odor serves as a cue for health- Gangstead & Thornhill (1998) female olfactory preferences favor the scent of more symmetrical men during ovulation-ovulating/non-pill uses consistently preferred the scent of symmetrical men-for contraceptive pill users and females not ovulating, there was no relationship-Herz & Inzlicht (2002) asked males and females to rank various physical characteristics in a potential partner• female body odor?⁃ singh and bronstad 2001 : males smelled female shirts from different times of their cycle (no contraception)⁃ 3 nights during Follicular phase (ovulating) and Luteal phase (non-ovulating)⁃ males lead to believe one t-shirt worn by attractive female, other by unattractive⁃ rated most attractive or sexy smell=during follicular phase⁃ lap dancer tips: solid line represents females not on contraception; dashed line represents females on contraception• the age factor:⁃ in chimpanzees⁃ males prefer older females, due to higher survivorship of offspring⁃ younger females are less experienced parents⁃ Buss (1989) : in a cross-cultural survey female preference was for someone around 4 years older⁃ Kenrick & Keefe (1992): females consistently married males who were around 5 years older than themselves• evolutionary explanation:⁃ this is a powerful cue to reproductive potential as women reach their reproductive peak around the age of twenty which declines thereafter• male age preferences:⁃ in studies of mate preferences, male desire females who are at their peak of reproductive potential⁃ Buss (1999) found that in every society (n=37), males preferred younger wives, on average 2 1/2 years younger⁃ as males age, they prefer mates who are increasingly younger (Kenrick & Keefe 1992)• what about teenagers?⁃ if teenage males prefer younger partners, these females may not be old enough to bear children⁃ we would therefore predict that teenage males would prefer slightly older females⁃ Kenrick (1996) asked teenage males and females (aged between 12-19) the ideal age of dating partner, and the age limits that would be acceptable⁃ teenage males (unlike older males) preferred mates who were slightly older than themselves⁃ however, they are unlikely to be successful in this because females (on average) at all ages prefer older males!• age preference changes at different relationship levels:⁃ Buunk (2001) examined minimum and maximum age preferences for mates across 5 different levels of relationship involvement in people age 20-60⁃ women preferred partners around their own age (regardless of the relationship involvement)⁃ males preferred mates at the peak of reproductive capability (18-30) for short-term relationships or sexual fantasies⁃ for long-term relationships males preferred mates around their own age or younger• sociocultural factors:⁃ in general, mate selection is limited to the norms of society⁃ the fact that females prefer older, higher status males and males prefer younger more attractive females may be a reflection of traditional gender roles⁃ but then why do we see this trend in so many cultures?• provide resources:⁃ human males can provide a range of resources for the female:⁃ food⁃ shelter⁃ protection from other males⁃ females should have evolved preferences for males who:⁃ have good resource prospects⁃ have higher social status⁃ display hard working and industrious characters⁃ what kind of males typically have these qualities?• evidence:⁃ women tend to value the economic resources of a potential partner substantially more than men do⁃ Trivers (1985) found that American men who marry in a given year generally earn 50% more money than men of the same age who do not marry⁃ Buss (1989) showed that women valued financial prospects around twice as highly as men• males earning capacity:⁃ Kenrick (1990) : minimum percentiles of