Evolutionary

Evolutionary

1. Family

   • Trivers (1974): parent + offsring should disagree over how long the period of parental investment should last/amount
   • Kin Selection/ Inclusive Fitness Theory (Hamilton, 1964)
     • Altruistic behaviours are favoured if relatedness+benefit to recipient > cost to actor
       • DeBruine (2014 for a review) into contextual and phenotypic cues
     • Bateson (1978): Optimal outbreeding theory
       • too close = genetic defects; too distant = hybrid incompatibility/ sterile offspring
         • Little et al. (2012): mixed-race face shape is preferred amongst both Europeans and Afircans = human preference for heterozygosity/diverse genes
   • Dawkins (1979): kin selection
     • special + complex. only invoked when 'indiv selection' is inadequate
     • Form of group selection. in groups selfless>selfish in terms of offspring production
     • only works for rare genes
     • expected to give each relative altruism proportional to the coefficient of relatedness
   • DeBruine (2005): trustworthy but not lustworthy. + effects of facial self-resemblance in prosocial/trustworthy contexts. Not the same affects on attractiveness (no effect on LT relationships where trust & attractiveness are important. and negative effecton ST where just attractiveneess is important)
     • DeBruine (2004): ratings of self-resembling attractiveness signif higher for same-sex (vs. opp-sex) faces -- self-resesmblance is used as a cue for kinship
   • mate preferences = based on parental sexual imprinting? (Jedlicka, 1980; Kendrick et al. 1998 ; Immelmann et al., 1991

2. Fathers

   • Fernandez-Duque et al. (2009):only 5-10% mammals exhibit paternal care
   • Pagel (1997): revealing paternity cues through physical cues may increase paternal care BUT concealing parternity may be ++ if there is a possibility of non-paternity and consequently neglect, abuse or infanticide
   • Daly & Wilson (1982): --videos of people right after birth-- paternal resemblance is more remarked upon than maternal
     • mothers allege paternal resemblance > fathers
     • Fathers will betray reserve/skepticism when others allege paternal resemblance
     • BUT -- mothers do not allege paternal resemblance more in his presence than absence
   • Christenfeld & Hill (1995): do babies ACTUALLY look more like their fathers?
     • children in general do not look like their parents enough for a resemblance to be detected (exception = 1y.o. look like fathers)
     • BUT could be due to things not captured by photos (e.g. mannerisms)

3. Fitness

   • Tybur & Gangestad (2011): mate prefs and infectious disease reviewed
     • benefits = less risk of pathogen transmission to self or offspring, also indirect benefits to boosting offspring fitness through heritability
       • costs = searching, missed opportunities (esp. if the male has no parenting effort = non-zero rejection rate means a loss of potential reproduction), trade-offs with other preferences
     • mates are preferred partly on the basis of cues to health. overt signs of infecction + sexually dimorphic features + symmetry + skin tone/colour
       • Jones et al. (2001): facial symmetry and judgements of aparent health (health = attractive)
       • Kalick et al. (1998): longitudinal data on facial attractiveness + health. adolescent attractiveness not related to health. BUT attractive people were rated as healthier than their peers. When attractiveness was controlled for, ratings of health were more accurate --> attarctiveness suppresses accurate recognition of health
     • prefs for seuxal dimorphism (spec. males) evolved at least partly to obtain INDIRECT genetic benefits for offspring. Prefs for skin tone = selected for DIRECT disease avoidance (research investigating the absence of overt signs are likely to also function for long term dieases avoidance but have yet to receive attention)
     • Gangestad et al. (2010): individuals rated as more physically attractive had lower oxidative stress (assoc w serious health problems)
     • Henderson & Anglin (2003): physical attractiveness covaries with longevity -> may relate to health
     • Evidence for relationship between attractiveness and health/immunocompetence = inconsistent. Weeden & Sabini (2005): only WHR + weight appear to be both predictive of health AND attractiveness. (symmetry + sex-typical hormonal markers failed to predict both/either
       • suggest a relationship in women but not with men
     • Boothroyd et al. (2005): healthiness of mens/womens faces reflect variations in skin tone + texture, but dont covary with measures of masculinity/femininity -> these dimensions reflect largely different qualities + highlight trade offs
     • DeBruine et al (2010): womens sensitivity to pathogen disgust covaries with prefs for facial masculinity in morphed and unmanipulated male faces.
       • moral, pathogen & sexual disgust; only pathogen = predictive
       • ARGUED: manipulated masculinity doesnt not = unmanipulated faces (Rhodes, 2006; Rennels et al, 2008)
         • BUT DeBruine et al. (2006/2010); demonstrates equvalent masculintiy prefs for manipulated and unmanipulated faces
       • Jones et al. (2013): pathogen disgust also predicts women's prefs for masculinity for in men's voices, faces and bodies
         • in men: salivary cortisol (biomarker for immunosuppression) and pathogen disgust predicts men's prefs for feminine cues in women's faces
       • Jones et al (2013): pathogen disgust predicts women's prefs for masculinity in mens voices, faces & bodies
     • Little et al. (2011) report that after exposure to visual pathogen primes, Ps demonstrate increased prefs for symmetry and sexual dimorphism in opp sex faces (but not same sex)
       • is health preferred in partners in a different way from general social partners? Still dont know whether this is due to direct pathogen avoidance or indirect genetic benefits.
       • fluctuating asymmetry = inbreeding/mutation/homozygosity OR nutrient deficient/parasite --- symmetry = contagion avoidance OR healthy genes
       • Moller (1997): review of whether symmetry = quality
   • Stephen et al. (2009): facial skin colouration affects perceived health of human faces -- spec red, yellow and light skin colours as health cues -> blood colour + high carotenoid + low melanin
     • Fink et al. (2006): skin colour distribution (independent of facial form and skin surface topography) has a major influence on perception of female facial age, attractiveness + health
       • Fisher et al (2014): the extent to which faces with low levels of adiposity were rated more ++ than faces w relatively high levels was greater for faces with healthy colour cues (vs. unhealthy)
   • de Barra et al. (2013): frequency of illness in childhood (spec. dihorrea) was positively correlated with prefs for exaggerated sex-typical characteristics in opp-sex (not same-sex) faces. Even stronger in those with current poor health
   • Thornhilll & Gangestad (1993): averageness + symmetry = attractive. average reflects high indiv protein heterozygosity and therefore an array to proteins to which parasites must adapt (important defense). symmetry = certification of overall phenotypic quality and developmental health --- parasite driven selection
     • 2006: sexual dimorphism covaries with self reported frequency of respiratory infection (but not gastrointestinal) over the past 3 years (men + masculinity = fewer whilst women + masculinity = more)
   • Gangestad & Buss (1993): across nations, parasite pravalence covaries with the degree to which physical attractiveness is prioritised.
   • DeBruine et al. (2010): reported relationship between nations health (mortality rate /life years lost to infectious disease) and women's prefs for male facial masculinity
     • Brooks et al. (2011) questioned robustness; DeBruine et al. (2011); response
   • Wincenciak et al. (2014): the relationship between partner choice and preference for health in oppsex face is moderated by the women's own attractiveness. -- builds on biological market theories where more attractive can better translate their preference into choice (e.g. can be more picky)

4. Fighting

   • Mueller & Mazur (1997): Facial dominance predicted rank in military cadets (social status)
   • Sell et al. (2009): accurately predict strength from facial cues of Bolivian horticulturists
   • Fink et al. (2007): hand grip strength correlates with both facial masculinity and dominance (physical strength)
   • Carre & McCormick (2008): mens face width-to-height ratio predicts aggression in lab tasks and in ice hockey players
   • Quist et al. (2011): correlation between facial masculinity and psychometric dominance in women
   • Watkins et al. (2010): taller men are less sensitive to cues of dominance in other men
   • reproductive success (Apicella et al. 2007) and potential (Rhodes et al., 2005) all correlated with indices of men's dominance
   • Masculinised men's faces (Jones et al. 2010a) and voices (2010b) are perceived to be more dominant
   • Vaz et al., (2002) height correlated with mens physical strength; aggression (Archer & Thanzami, 2007); fighting ability (von Rueden et al. 2008), reproductive success (Pawlowski et al, 2000) and social status (Hensley, 1993)
     • risky to incorrectly perceive rivals dominance -- perhaps not if you're very dominant yourself -> dominant men may be less sensitive to cues of dominance in rivals
       • Watkins et al. (2010): men perceived masculinised versions of men's faces and voices to be more dominant than femininised versions. This effect of masculinity on perceived dominance was less pronounced among tall men -> potentially as they will incur fewer costs if they incorrectly perceive it
   • Watkins & Jones (2012): men randomly allocated to priming conditions in which they imagined losing confrontations subsequently demonstrated greater sensitivity to dominance cues than those assigned to winning conditions. No such effect for trust (spec to competition-related perceptions)
     • as well as being more salient to some people, dominance cues are also context dependent
     • Are social and physical dominance related in men (Mazur & Booth, 1998)? OR does social status allow then greater protection from physically dominant rivals (von Rueden et al., 2011)?
       • 'losers' found cues of other men's dominance more salient than 'winners' -- effect not modulated by the type of confrontation (argument vs fight) -- effect specific to dominance (suggests degree of specialisation

5. Fertility

   • Shifts across menstrual cycle: argued that oestrous mate preferences weigh cues of intrinsic genetic benefits more heavily than their prefs outside the fertile phase. Womens mate preferences for a variety of masculine features function most markedly to acquire mates of high genetic quality rather than motivate disease avoidance (Thornhill & Gangestad, 2008)
     • In sum: documented changes in women's prefs across the menstrual cycle suggest at least partialy distinct functions of prefs for sexual dimorphism and healthy appearance (latter appears to function more strongly as a means of avoiding disease)
       • Fessler (2001): women adaptively engage in disease-avoidance behaviours to avoid contact with pathogens during the sensitive luteal phase
         • Jones et al. (2005): reported no relationship between high fertility and womens emphasised incrased attraction. BUT stronger during luteal phase -> indicates raised progesterone assc w increased attraction to facial cues assoc w possible direct benefits and suggest prefs are influenced by adaptations that compensate for weakened immune system responses during pregnancy and reduce the risk of disrupting foetal development
       • Healthy face morphs are more attractive in luteal phase than in late-follicular phase of cycle
         • follicular = most fertile; luteal = blastocyte implants
   • Little et al. (2011): REVIEW
     • Buss & Barnes (1986): both men and women are highly concerned with good looks in a potential partner
       • Langlois et al (2000): certain features are attractive across individuals and cultures and are treated more positively
         • Dion (1972): what is beautiful is good
         • Wolf (1991): initially suggested that cultures vary dramatically in what is perceived to be attractive
           • although true considering cultural practices such as neck lengthening/teeth filing/lip ornaments/being fat in Africa
     • Rhodes (2006): meta-analyses -- traits such as symmetry, averageness and secondary sexual characteristics all attractive
     • direct benefits = good for you + offspring AND liked in same and opp sex. indirect = preferred only in opp sex & benefits sprogs
   • Penton-Voak et al. (1999): more attentive to phenotypic markers indicating immunological competence during follicular phase + otherwise prefer slightly feminised faces which could indicate positive personality attributions
     • SImilar results for vocal masculinity (Feinberg et al. 2006); masculine body shape (Little et al. 2007); dominant body odours (Havlicek et al. 2006); symmetric BO (Gangestad et al. 2010) & displays of male dominance (Gangestad et al. 2004)
       • Guegen et al (2009): women more receptive to courtship invitations around ovulation
         • --> cyclic shifts reflect a dual mating strategy to maximise benefits ? cukoldry explanation (one man raises whilst another is the father)
           • 1. Generally open to relationships w feminine men (esp. LT); 2. more open to ST relationships with masculine men around ovulation --- VERY CONTROVERSIAL
             • Evidence -- mate guarding increases at ovulation (esp with uglies) (Haselton & Gangestad, 2006); women w masculine partners = smaller cyclic shifts in preferences (Gangestad et al., 2010); shifts are greatest when partnered women judge mens attractiveness for ST relationships (penton-voak et al., 1999)
               • Little & Jones (2012): prefer masculinity + symmetry when fertility is highest + judging the faces for ST relationships. No effect of cycle for LT. (used within + between Ps)
                 • Gangestad et al. (2004): ST relationships = greater evidence of cyclic shifts. greatest prefs for dominance = ST + @ day 11 (follicular/ovulationi)
                   • Gildersleeve et al. (2014): 2 meta-analyses -- robust evidence for cyclic shifts (V>ROBUST for ST)
                     • Wood et al (2014): reported absence of cyclic shifts in meta-analysis
   • Jones et al. (2005): link between progesterone levels and womens prefs for masculine traits in faces; and voices (Puts 2006) -- raised prog = preparing for pregnancy = prefs for feminine men/caring
     • Roney et al. (2011): estrogen levels correlated with prefs for high-testosterone mens faces -- BUT other studies = no link (Welling et al. 2007): but they did report ^salivary testosterone = ^ attraction to masculine faces across cycle
   • Menopause causes shift in mating-orientated to family-orientated psychology; femininity prefs in women and men (younger+age matched) (Vokovic et al., 2009; Little et al., 2010; Jones et al. 2011)
     • Feinberg et al. (2008): masculinity prefs positively correlated across faces+voices. Women on pill = weaker facial+vocal masculinity prefs and weaker assoc btwn masculinity prds across modalities (vs. not on pill)
       • Roberts et al. (2012): NO pill = higher sexual satisfaction but lower commitment satis (pill users = opposite)
   • Kandrick et al. (2014): scarcity of female mates determines sociosexual orientation (ST/LT prefs) for both men and women (not predicted by environmental demand or wealth factors). Less willing to engage in uncommitted sexual relatiomships when demale mates were scarce
   • Jones et al. (2015): red facial coloration reflects changes in estradiol (within study) -- supports changes in facial colouration = cues of fertility

6. Frequency

   • voice pitch influenced by hormones
   • Testes volume is a predictor of voice pitch in teen boys (Harries, 1997) but not adults (Simmons et al., 2011)
   • Dabbs & Mallinger (1999) testosterone = negatively correlated with voice pitch
     • Ackman et al. (2004) inject women with testosterone & their voices get more masculine -- postmenopausal women also have lower pitched voices
   • Bryant & Haselton (2009): pitch was higher in ovulating women vs low fertility stages in cycle -- suggests fertility cue
     • men think high pitched women = attractive, younger, smaller, feminine, healthy -- women think low pitched men = attractive older larger masculine dominant healthy
   • Hadza (Tanzania) -- modern birth control methods mean its difficult to test whether more sexually dimorphic voices = greater reproductive success
     • Apicella et al. (2007): voice pitch not related to reproductive outcomes in women BUT men with low voice pitch have higher reproductive success + more children born to them (but does not predict child mortality)
       • Why men & not women? More mates, shorter inter-birth intervals, start reproducing earlier. Maybe just more subtle effect in women?
     • Apicella & Feinberg (2009): both men + women see lower pitch in the opp sex = better at hunting and gathering. Men preferred higher pitched women as marriage partners but women showed no preference in men. (BUT breastfeeding women showed a pref for higher pitched men)
       • testosterone assoc with dominance, immunocompetence and low paternal investment; this illustrates the trade off between securing good genes and paternal investment?
   • Pisanski et al (2014): changes in salivary estradiol predict changes in women's prefs for vocal masculinity

7. Fucking

   • Malamuth (1996): porn features positively valenced cues (e.g. female partners with adaptive characteristics)
     • Mens ST mating prob -- content of male porn
       • sexual access to women -- women eager to "service" men sexually
       • identifying fertile women -- youthful women with shapely bodies (cues to fertility)
       • minimising investment -- casual sex
       • partner number problem -- numerous women depicted
     • male porn reflects ST male mating strategy whilst female reflects LT orientation
       • media industry has capitalised on evolution-based mechanisms of sexuality
     • female LT mating probs -- content of female porn
       • identifying man able + willing to invest -- high status man who desires and eventually loves only her
       • physical protection -- man is powerful and "brutish" towards others
       • identifying man with good parenting skills -- man becomes kind and gentle by end of story
   • Pound (2002): sperm competition has been an important selection pressure -> sexual arousal to sperm competition = adaptive response (frequent sex increases paternity chances)
     • women + multiple men = more prevalent than man + multiple women
       • Self-reported preferences + image selection both yielded supporting results
     • McKibbin et al. (2013): supporting sperm competition -- DVDs with 1 women and 2+ men predicted sales rank (2+ women and one man does not)
   • Kilagallon & Simmons (2005): males adjust ejaculate expenditure according to the risk of sperm competition -- males viewing images depicting sperm competition had a higher % of motile sperm in their ejaculates.
   • Salmon & Symons (2004): romance novels and porn highlight differences between male and female erotic fantasy (both multibillion $$ global industry)

8. Henrich et al. (2010): the WEIRDest people in the world?