Question

1. One of the most robust findings regarding the differences between the genders is that men are often more risk seeking than women. This is likely explained by different pressures on the two sexes when it comes to child-rearing.

a. What limits the number of offspring that women can pass their genes on to? ___________________ __________________________________________________________________________________ __________________________________________________________________________________

b. What limits the number of offspring that men can pass their genes on to? ______________________ __________________________________________________________________________________ __________________________________________________________________________________

c. In light of a), how do you expect women select mates? _____________________________________ __________________________________________________________________________________ __________________________________________________________________________________

d. In light of b), how do you expect men select mates? _______________________________________ __________________________________________________________________________________ __________________________________________________________________________________

e. What determines whether a woman is successful at passing on her genes to more offspring than her peers? ____________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________

f. What determines whether a man is successful at passing on his genes to more offspring than his peers? ____________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________

g. How can this explain risk lovingness in men relative to women? ______________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________

Answer 1

Reproduction occurs by passing on genes which are the "blueprint" for inherited traits. If an organism "survives" without passing on traits, its survival "doesn’t count" in evolution.

Every individual has only so much energy. Some energy is spent staying alive — that is, finding food and not being somebody else's food — and what's left over can be spent on reproduction. In other words, there are limits to reproduction. Of course, the various slices of that reproductive energy pie also vary between males and female of all species.

(a) The female reproductive pie is much more complex. There are costs to pregnancy, lactation for mammals, and then whatever else is needed to bring a kid up to sexual maturity so they can pass on genes as well. But there are all sorts of ways, from an evolutionary point of view, for females of a species to distribute that energy and bring up babies successfully. She might have as many babies as she can in one shot, litters that is, and have them as often as possible. For that kind of female, reproduction is an assembly line of cheap production per kid. Or a female might opt for the other end of the scale and make one baby at a time and wait for a very long time to see if that one investment pays off. Obviously, humans are on slow side of the baby production continuum. Evolution has selected for this path because there are features of our species that require great investment by mothers. Human infants might have big brains compared to other mammals, but they need to get even bigger once outside the womb. And so human infants are actually born neurologically unfinished. They can’t cling, sit up, feed themselves, or run from predators. And so the very nature of what it takes to be an adult human puts constraints on how many children a mother can have at a time.

Women can reproduce for about half of their lifetime and can only give birth about once every year or so. So it makes sense that women can only have a fraction as many children as men . One study estimated a woman can have around 15 pregnancies in a lifetime and depending on how many babies she births for each pregnansy, she'd probably have around 15-30 children.

(b) The various slices of that reproductive energy pie also vary between males and female of all species. Males don't gestate or lactate so they pass on the most genes by flitting from female to female making as many babies as they can, and then walking away.

(c) In humans, when choosing a mate of the opposite sex, females place high preference for a mate that is physically attractive.This ties in with the idea that women discriminate between men on hypothesized fitness cues. The more physically attractive a man is, the higher his fitness, and the better his genes will be. Women are attracted to more masculine traits (e.g. strong jawline, a more muscular body). Indeed, men who are more masculine tend to have a higher number of sexual partners.

Women seem to judge potential mates by how masculine their features are, new research shows. Men with square jaws and well-defined brow ridges are seen as good short-term partners, while those with more feminine traits such as a rounder face and fuller lips are perceived as better long-term mates.Male physical attractiveness: Immunocompetence Handicap Hypothesis,Waist-to-chest ratio, Fluctuating Asymmetry,Resources,Age.

(d) It is a well-known fact that men assign as far greater salience to the attractiveness of a potential mate when considering their mating preference than women do.

Body shape and size: The first factor that has been shown to impact mating preference in males is that of Waist Hip Ratio (WHR), that is the relationship between waist circumference and hip circumference, as it has been suggested as a marker of age, reproductive status and health. It was also found that women with a WHR of 0.7 were rated the most attractive, youthful, fertile and healthy, when compared to other WHR's. Furthermore, the current research also found that those women with a WHR of 0.7 and of normal weight were rated the most attractive, and whereas those with a WHR of 0.7 but whom were underweight were rated as more youthful but not as attractive. An extension of WHR research showed that there is an impact of breast and hip size upon attractiveness; Women with large breasts, and small hips were rated more attractive than women with small breasts and small hips, as well as finding that women with large hips were rated less attractive irrespective of breast size.

Skin condition: Skin condition has been found to be an honest indicator of sex hormones which may indicate levels of fertility. The study directly examines the relationship between an individual having acne and the levels of hormones that could potentially indicate low fertility, therefore guiding attractiveness for mate preference. This skin condition, attractiveness link has been corroborated by research that found that skin colour, skin homogeneity and facial adiposity (how fat is deposited around the face) all predict female attractiveness and therefore, mate preference. Skin tone has also been found to be an honest indicator of youthfulness and fertility; as well as research showing the first links between estradiol and female facial redness, in which as a woman reaches the peak of her ovulatory cycle her facial redness increases. This research would suggest that male mate preference would be guided by the individuals skin tone, looking for women with redder facial skin tones they indicate peak fertility and optimal opportunity for reproductive success.

Neoteny: Males show a preference for neotenous or youthful looking features in women, such as; big eyes, a small nose, and full lips.These features act as a signal of fertility as they are caused by high estrogen and low testosterone. As a result of evolution these features are deemed as highly attractive as they would indicate a higher chance of successful reproduction. This male mate preference for neoteny has been shown in research in which men were asked to morph images of female faces until an ideal face was achieved.

Chastity: Chastity is deemed highly desirable across cultures however the extent of its importance shows some variation. The importance of chastity to males, in an evolutionary sense has been linked to paternal certainty; as before contraception, the only way to ensure a woman had not been inseminated by another man was if she were chaste.

(e)Females have limitations such as gestation time (typically 9 months), then followed by lactation which suppresses ovulation and her chances of becoming pregnant again quickly.In addition, a females ultimate reproductive success is limited due to ability to distribute her time and energy towards reproducing.The metabolic task of converting energy from the environment into viable offspring falls to the female, and the rate at which she can produce offspring is limited by the rate at which she can direct metabolic energy to the task The reasoning for the transfer of energy from one category to another takes away from each individual category overall. For example, if a female has not reached menarche yet, she will only need to be focusing her energy into growth and maintenance because she cannot yet place energy towards reproducing. However, once a female is ready to begin putting forth energy into reproduction she will then have less energy to put towards overall growth and maintenance.Females have a constraint on the amount of energy they will need to put forth into reproduction. Since females go through gestation they have a set obligation for energy output into reproduction.

(f) Males, however, do no have this constraint and therefore could potentially put forth more offspring as their commitment of energy into reproduction is less than a females. All things considered, men and women are constrained for different reasons and the number of offspring they can produce. Males contrastingly are not constrained by the time and energy of gestation or lactation. Females are reliant on the genetic quality of their mate as well. This refers to sperm quality of the male and the compatibility of the sperms antigens with the females immune system.If the Humans in general, consider phenotypic traits that present their health and body symmetry. The pattern of constraints on female reproduction is consistent with human life-history and across all populations.

A difficulty in studying human reproductive success is its high variability. Every person, male or female, is different, especially when it comes to reproductive success and also fertility. Reproductive success is determined not only by behavior (choices), but also physiological variables that cannot be controlled.

(g)People tend to perceive that women are more risk averse than men. Stronger, taller, and more attractive people are perceived to be more risk tolerant.Women are perceived to be more risk averse. That means that women are at a disadvantage when it comes to getting support for risk-taking.