Gender Differences

There is a curiously modern confusion about the difference between boys and girls. In the age of democratic idealism and radical feminism, there is a tendency to demand equality for male and female and to insist that both sexes are equally suited or females are better suited to fulfill all human identities and roles. There is confusion about what the differences are and who does what to whom. Old prejudices prevail and wrong ideas flourish. Any meaningful discussion of gender differences must begin with the recognition that body and psyche gender may not match. Not all females think, feel and act like females and not all males think, feel and act like males.

You do not require a scientist to tell you that girls and boys are different and will inevitably pursue different goals and interests or the same goals and interests differently. What the scientist can do is  measure and account for gender differences in a more precise manner. This is not to argue that women should be denied any opportunity that is available to them. It is to argue that women should expect to be treated equally in terms of job opportunities, pay, promotion and social benefits. This is to argue that men and women are different and often do best pursing divergent social and professional paths. The needs, strengths and weaknesses of each gender can be better understood. The negative impact of gender differences is minimized if they are recognized and each person develops appropriate expectations.

Everyone knows that the genotype, chromosome pair XX, produces the female phenotype and the XY chromosome pair denotes male. Men inherit their X chromosomes from their mothers and are vulnerable to genetic defects carried on the X chromosome such as color blindness and fragile X syndrome, a form of mental retardation.  Normal variation allows for body sex to have a different mind sex and for sexual experimentation that goes beyond innate determinants. Not all girls like boys or fall in love with boys; not all girls act like girls and not all girls feel like girls inside. A similar variation is seen in boys. Even individuals who start out with congruent body and psychic gender may be altered by hormones, environmental factors, foods, injury, drugs, chemical pollution and disease.  The expressions of sexual programs in the brain change with the chemical and hormonal milieu in the body. 

You could argue that feminine and masculine traits can be mixed in a variety of ways in bodies that have either male or female sex organs. The penis and vagina do not guarantee the gender of the mind. Every woman carries a double dose of the X chromosome. One of X chromosomes is fully expressed and the other is selectively expressed. Willard and Carrel found that 15% of the genes on the inactive X chromosome were active in every human sample they examined. Another 10% of genes from the inactive X were expressed in some of the samples.  They concluded that "Every female is expressing a different subset of X-linked genes at different levels.” They suggested that women get a higher dose of these genes than men; these genes may underlie traits that differ between the sexes and traits that differ among women.   

Mixed genders need not be programmed in DNA but may be developmental variations. If the chromosomes are intact, male and female bodies are created. The XY chromosome pair specifies testes that produce testosterone in utero. The XX chromosome pair specifies ovaries that produce estrogen in utero. The body sex has to be linked to brain programs that determine the gender characteristics:  gender-image, gender feelings, gender-specific social priorities, gender behavior, mate attraction and bonding.

All embryos are females until turned into males; the critical event for males is the secretion of androgens in utero. The androgen signal is required to match a male psyche with the male body. In the absence of testosterone, mammals develop along feminine lines, regardless of genetic sex. Oddly, high doses of estrogen and other steroids prenatally can also masculinize a fetus. Testosterone promotes the growth of a male set of ducts and dihydrotestosterone directs the growth of the penis and scrotum. Both hormones influence brain development. The simplest brain sex-determining rules are:

If the androgen signal is weak or absent in utero and/or shortly after birth, the brain continues on a female course.

A female embryo can be converted to a male psyche with a female body by too much androgen in utero.

A female embryo can be defeminized by blocking early estrogen.

The hypothalamus and amygdala are prime targets for sex hormones.

Fich and Dannenberg suggested that animal research revealed the basic patterns of hormone influence on the development of male and female behaviors. For example, they stated: "The manipulations of neonatal androgens affected adult sexual behavior. Female guinea pigs exposed to testosterone by various regimes during the prenatal period increased male-typical sexual behavior (mounting). These subjects also decreased female-typical behavior (lordosis) when, as adults, they were gonadectomized, primed with estrogen and progesterone, and tested for sexual receptivity. Similarly, male rats castrated at birth reduced male-typical sexual behaviors and increased feminine behaviors in adulthood.  These same behavioral patterns were seen in adult male rodents exposed prenatally to stress or alcohol, which disrupts the prenatal testosterone surge in male fetuses. These effects are mediated by aromatization of testosterone to estrogen, since sexual behavior can be masculinized in females and reinstated in neonatally castrated males with early administration of a synthetic estrogen or high doses of estradiol. Estrogen has also been shown to act asymmetrically in the hypothalamus to modify reproductive behavior of the female rat. Estradiol pellets were placed in the left or right ventromedial nucleus during the first two days of life. In adulthood, subjects were ovariectomized and primed with estradiol benzoate and progesterone. Subjects with left-sided implants showed reduced lordosis as compared to right-sided implants and cholesterol control. Nordeen and Yahr also found masculinizing effects of estradiol, with local implantation in the right preoptic area leading to increased mounting behavior in adulthood."

Without selective breeding practices, the male/female ratio is remarkably constant in human populations. Preference for male offspring in Asia and Africa has produced alarming increases in the male population. Female fetuses are selectively aborted and female newborns are neglected or killed. Hesketh and Zhu Wei Xing suggested:” There are an estimated 80 million missing females in India and China alone. The large cohorts of surplus males now reaching adulthood are predominantly of low socioeconomic class… their lack of marriageability, and consequent marginalization in society, may lead to antisocial behavior and violence, threatening societal stability and security. 

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I and Thou

The Psychology & Philosophy series was developed by Persona Digital Books. The books are copyright and all rights to reproduction by any means are reserved. We encourage readers to quote and paraphrase topics from I and Thou  published online and expect proper citations to accompany all derivative writings. The author is Stephen Gislason and the publisher is Persona Digital Books