Answer to Question 1
a
Answer to Question 2
More men than women seek opportunities for casual sexual relationships with many partners. Why? From the evolutionary standpoint of spreading one's genes, men can succeed by either of two strategies: Be loyal to one woman and devote your energies to helping her and her babies, or mate with many women and hope that some of them can raise your babies without your help. No one needs to be conscious of these strategies, of course. The idea is that men who acted these ways in the past propagated their genes, and today's men might have inherited genes that promote these behaviors. In contrast, a woman can have no more than one pregnancy per 9 months, regardless of her number of sex partners. So evolution may have predisposed men, or at least some men, to be more interested in multiple mates than women are.
Almost all people prefer a romantic partner who is healthy, intelligent, honest, and physically attractive. Typically, women have some additional interests that are less common for men. In particular, women are more likely than men are to prefer a mate who is likely to be a good provider. According to evolutionary theorists, the reason is this: While a woman is pregnant or taking care of a small child, she needs help getting food and other requirements. Evolution would have favored any gene that caused women to seek good providers. Related to this tendency, most women tend to be cautious during courtship. Even if a man seems interested in her, a woman is generally cautious before concluding that he has a strong commitment to her. She would not want a man who acts interested and then leaves when she needs him.
Men tend to have a stronger preference for a young partner. An evolutionary explanation is that young women are likely to remain fertile longer than older women are, so a man can have more children by pairing with a young woman. Men remain fertile into old age, so a woman has less need to insist on youth. Women prefer young partners when possible, but in many societies, only older men have enough financial resources to get married.
Traditionally, in nearly all cultures, men have been more jealous of a wife's possible infidelity than women have been of a husband's infidelity. From an evolutionary standpoint, why? If a man is to pass on his genesthe key point in evolutionhe needs to be sure that the children he supports are his own. An unfaithful wife threatens that certainty. A woman knows that any children she bears are her own, so she does not have the same worry. (She might, however, worry that her husband might start supporting some other woman's children, instead of her own children.) The degree of jealousy varies among cultures. Some cultures tolerate sexual infidelity by husbands, and some do not, and the intensity of prohibition against wives' infidelity varies, but no known society considers infidelity more acceptable for women than for men.
Which would upset you more: if your partner had a brief sexual affair with someone else, or if he or she became emotionally close to someone else? According to several studies, men say they would be more upset by the sexual infidelity, whereas women would be more upset by the emotional infidelity. However, those studies dealt with hypothetical situations. Most men and women who have actually dealt with an unfaithful partner say they were more upset by their partner's becoming emotionally close to someone else than by the sexual affair.
Brain Dissection
Schizophrenia and the Brain الفصام والدماغ
Facet of superior articular process
Superior view of lumbar vertebrae
Use the power rule to find derivative
Two major types of nerve circuits in the brain