Mate_Preference_in_Humans

Introduction Trivers theory of parental investment has identified the difference between investments of each sex; in relation to costs of reproduction have lead to strategies to optimise behaviour, through mate preferences (Trivers 1972). With increased energy costs, through gestation and lactation for females it is presumable that females will be the choosier sex, therefore developing mate preferences. Although females may be the more choosier sex, males also have had to develop mate preferences in response to the limited access to females partners, therefore they have had to develop strategies which will enable them to choose a fertile female and increasing chances of fertilisation, therefore strategies to pick up female fertility cues have been developed (Chu et al 2007). Gangstad and Simpson (2000), identified that the two most important driving factors of female mate choice were based upon potential partner’s genetic quality and contribution of resources and investment to offspring, supported by : Buss (1989), Buss and Barnes (1986). Symons (1979) recognized that physical attractiveness reflects mate preference to healthy mates and mates with increased fertility and increased genetic quality. Physical attractiveness has therefore been described as the “ ‘phenotypic condition’ – the ability to acquire and allocate resources efficiently and effectively to activities that enhance survival and reproduction (i.e. the ability to garner and convert energy into returns in evolutionary fitness)”. Thornhill and Gangestad (1999) page 452. The “phenotypic condition” can be recognised in males as symmetry, facial hair, tall and big body size to reflect increased genetic quality and health, with females having preference to this in hope that these traits can be passed on to offspring thus providing them with traits which will give them selective advantage of increased reproductive success. In females the “phenotypic condition” is displayed to indicate increased fertility through signs of youthfulness, slim body and being physically attractive. Therefore due to the “phenotypic condition” reflecting health and fertility, both males and females will have a preference for physically attractive partners and they themselves will want to portray themselves as physically attractive to increase chances of mate selection. Willingness of a male to provide investment and parental care for offspring as described by Borgerhof Mulder (1989): Voland and Engel (1990) may be directly associated with wealth of the male. Buss (1989), using cross cultural studies found that females had an increased preference to wealth and resources than males, supported by the “lonely hearts” analysis by Waynworth and Dunbar (1995), where common interests in potential partners included wealth and status. This then leads to the notion that females would have a preference to mate with older males, since wealth increases with age. It is also necessary to take into account,that with increased age follows increased morality, leaving the female to increase her investment to the child due to only one parent present, which will be more years of increased investment with an older male than it would be with a younger male. The genetic quality will also be lower as age increases and so for these reasons Waynworth and Dunbar (1995) describe a “hump shaped” preference to male age. On the contrary, males will however always prefer younger women due to their increased fecundity; therefore younger women will be able to increase their reproductive success and reproductive value. Fecundity is also correlated with body size and with ideal body sizes such as those described as ‘slim’ being that of male preference. These types of body sizes are ideal for reproduction of offspring, thus increasing reproductive success of males who mate these females. Following the previous literature as discussed, the following predictions of the present study will include; 1. Females will prefer males somewhat older than them; whereas males will always choose younger women. 2. Females will have more of a preference to wealth in potential partners than males do in women. However males will advertise wealth more than females. 3. Males and females both will have a preference to physically attractive partners; therefore both will advertise physical attractiveness highly. 4. Females will have a preference to males who advertise commitment more, than males do in females, with males advertising commitment more than females. 5. Females will have a preference to taller males. Null Hypothesis There will be no significant difference between males and females in any trait, other than due to chance. Methods 20 male and 20 female personal advertisements were taken from the national paper The Guardian; these were arranged, classified and coded under ranked categories, Table 1. The coded categories were used for age, height, body size and wealth for both description and looking for. Following on from previous literature from Buss (1989) and Thiessen et al (1993), word associations were categorised as described in table 1. Singh (1993) associated words which reflected fecundity through associations of youthfulness and ideal body shape (e.g. slim) for cues for increased possibility of reproductive success; these are described in table 1. Wealth and status in correlation to Borgerhof Mulder (1989): Voland and Engel (1990), were used to identify advertisements of available resources, again summarised in table 1. To compare advertisements in both looking for and description of: Physical attractiveness, family commitment, hobbies and personality, the frequencies of times mentioned was recorded. Due to the fact that The guardian. Appeals mainly to middle class, wealthier people and that unlike the metro for example which is a free national paper, the fact that people who choose to read The guardian, have had to pay considerably more already show a preference to wealth and status, this therefore will be taken into consideration in the results and therefore results of this present study will be compared to previous studies who looked at advertisements of papers appealing to working class people, and see if this also may have an effect upon mating preferences. Table 1 Word associations and categories. Physical attractiveness Wealth/Status Family Commitment Cute, handsome, fit, good looking, attractive, hunk, well built, slim Occupation High standard lifestyle, e.g. good food, holidays. Caring, sensitive mature, gentle. Table 2 (a) Coded traits, for descriptions. Score Age Height Body Size Wealth 1 20 0 30 4.5-5.0 Small Stated 2 31 0 40 5.0-5.5 Medium Not stated 3 41 0 50 5.5-6.0 Large 4 51 0 60 6.0-6.5 5 61 + 6 Not Specified Table 2 (b) Coded traits, for Looking For. Score Age Height Body Size Wealth 1 Younger Shorter Small Stated 2 Older Taller Medium Not Stated 3 Same Age Same Height Large 4 No Preference No Preference  Results  Figure 1. Graph to shw ages of male advitisors and age of women looking for.  Figure 2. Graph to show ages of male advertisers and age of women looking for.  Table 3.Mean and p value from t-test results of male and female of the frequency of traits mentioned in description (a) and Looking for (b). (a) Trait Male Female P Value Physical Attractiveness 0.55 0.75 0.438 Hobbies 1.05 1.3 0.63 Personality 1.75 1.85 0.86 Commitment 1.84 0.55 0.008 (b) Trait Male Female P Value Physical Attractiveness 0.25 0.15 0.50 Hobbies 0.1 0.2 0.467 Personality 1.5 0.5 0.011 Commitment 0.35 1.35 0.000 Discusssion Results from chi squared analysis found that there was significant difference between males and females in what age of potential partner they were looking for with p value less than the critical value o.o5 (p value was 0.002). Figure 1 shows that males, between the age range of 20-61+ preferred women from the 20-31 category on the whole, with one males choosing female of age 31-40. This supports the prediction that males will choose females younger than them. Females on the other hand, those who stated preference of age all chose males in the 31-40 age (figure 2) this correlates with the predication that although older males accumulate more money, females will also have to balance the genetic quality in the choice of males as with increased age, decreases genetic quality and increases morality, therefore this age gap should be the correct balance needed for a female, with no female choosing younger men of age 21-30. Chi squared analysis also found a significant difference between height of advertisers and of potential partners in both male and females, with both sexes having no preference in height of partner. This finding goes against the prediction that females may choose taller males as height as an indication of genetic quality. Chi squared analysis also revealed a significant difference between males and females in advertisements of wealth in (p value 0.05), with more males mentioning wealth in description than females and more females mentioning wealth in looking for than males did when they described potential; partners they were looking for. Although slight differences can be seen through what each sex emphasised in their descriptions (table 3), females for example showing a higher mean score in the frequency of times physical attractiveness was mentioned (mean score 1.3), than the frequency of times males mentioned physical attractiveness in their description (mean score 1.05), p values of the 2 sample t-test for males and females were found to exceed o.o5 (table 3). The results of the t-test for males and females in the looking for sector, found no significant difference between the frequencies of times physical attractiveness was mentioned by each sex (p value 0.5), meeting the hypothesis that males and females will both advertise for potential partners with increased physical attractiveness. Similar results were found for hobbies and personality of descriptions, where slight differences were found but the differences were not significant , with p values greater than 0.05. The only significant difference seen between males and females in the descriptions of themselves was for commitment (p value = 0.008). Males more significantly mentioned commitment in their descriptions (mean frequency, 1.84), whereas females mentioned commitment significantly less (mean score, 0.55). Again, in the t-test for males and females in looking for, a significant difference was found ( p value 0.00) with females showing a larger mean score of mentioning commitment in their looking for partner section ( mean score 1.35), whereas males had significantly low mention of commitment needed in their female partner they were looking for (mean score 0.35). The results from the t-tests therefore support the hypothesis that females will choose advertise for males with increased potential of parental investment and commitment, with males with increased advertisement of commitment. The only other findings which showed a significant difference between sexes in their looking for profiles was for personality, with males mentioning personality of potential partner more than females did for potential male partners ( males looking for mean score = 1.5, females = 0.5). Where no significant results were found between males and females in both description and looking for, possible explanations of this may be explained through the idea of the “like attract” decision model (Buston and Emlen 2003). Although the present study only focused upon the reproductive potential of an individual as the derivative of mate choice Bereczkei and Sanaky (1996) have highlighted the importance of the stability of the partnership as equally as important as optimal reproductive potential choice in partner. Where pairing of individuals occur with different quality as themselves, may lead to the partner with greater genetic quality to trading up to a partner with greater genetic quality when opportunities arise. Natural selection therefore would favor strategies which will choose partners for long term relationships which are of similar genetic quality as themselves, to reduce risk of desertion from partner, this choice therefore will be dependent on an individual’s self perception of themselves (Noe and Hammerstein 1995, Paulowski and Dunbar 1994). These findings therefore will account for the non significant difference in advertisements for looking for and description of physical attractiveness, hobbies and personality (only looking for section for both sexes was not significant) in both males and females. Another factor found to be significant on self perception and mate choice is that of the relative quality of other potential mates available within the local population. Buston and Emlen (2003) proposed that females would lower self assessment relative to exposure to profiles of more physically attractive females (Brown et al 1992, Guitierres et al 1999). Males also would lower self assessment in relation to exposure of more dominant males (Guitierres et al 1999), this may play a significant role when advertising in The Guardian, due to the fact that the paper itself is read by very successful, educated and wealthy people, therefore it is more likely that the relative population of males in the readership of the paper will be classed as dominant males. The effect of self assessment in response to the relative quality of the population may also account for the unexpected results of no significant difference of physical attractiveness between males and females (p value 0.5 from 2 sample t-test). The factors summarised as the “likes attraction” descion rule proposed by Buston and Emlen (2003) although demonstrated in the present studies may be responsible for some unexpected results of mate choice, many evolutionary studies in previous literature have failed to account for this when considering mate choice. Therefore a further investigation from this present study may be an enhancement to include this descion rule following studies such as Buston and Emlen (2003) with encouraging support already found by Little et al (2000) who reported a positive correlation of women’s self perceived attractiveness with preference in masculinised and symmetrical facial features in partners.  The methodology of this present study has been widely critisced ( Buss 1989, Kenrick and Keefe 1992) with one of the major drawbacks that mate parings do not take place through personal advertisements conventionally, and does not viably reflect how mate choice actually occurs. It is also important to remember that those who do pick mates through this way have previously not been successful in mating with this method usually being a last resort. The success rate of actual pairing through personal advertisements has been generally low (Howard and Zemen 1998), proving that this is not how pairing actually occurs. The reasons for the low success rate is that many people advertising lie, with support that those who do pair through such advertisements actually pair with mates that do not actually meet there looking for criteria (Chu et al 2007). Another important consideration in generalisation of the represent study is that, the study only focused on a western society and again only results should be generalised to these class of people, although the basic evolutionary principals do seem sensible to apply, due to the fact that all individuals aim for reproductive success an natural selection will always favor the strategies that increase reproductive success, although in different societies they may be demonstrated differently e.g. resources in a western society may be linked to wealth as in money however in tribes it may be amount of land or ornaments held by an individual. Further investigation following on from this study should look to include comparison of other newspapers in comparison to a paper that appeals to the middle class audience; effects of children from different partners should also be included. The effects of self perception and relative quality of population should also be considered as described earlier by following the work of Buston and Emlen (2003). Work with different cultures and societies should also be reviewed so that universal generalisations can be made. References Bereczkei and Csanaky (1996) Mate choice, marital success, and reproduction in a modern society Ethol. Sociobiol 17 17–35. Borgerhoff Mulder (1989) Early maturing Kipsigis women have higher reproductive success than late maturing women and cost more to marry. Behav. Ecol. Sociobiol. 24 , 145–153. Brown et al (1992). J. Pers. Soc. Psychol. 62 , 717–727. Buss, D. M. (1989)Sex-differences in human mate preferences – evolutionary hypothesis tested in 37 cultures. 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