Ein Beitrag im Telegraph bespricht ein Buch des Entwicklungsbiologen Lewis Wolpert.
Heartiste hat den Inhalt der Zusammenfassung in Schlagwörtern zusammengefasst:
The biological differences that can be found between the bodies and brains of males and females are largely due to the way these embryos develop in the womb.
– There are also fundamental differences in brain development between men and women, which are clear from the early behaviour of children. A few hours after birth, girls are more sensitive than boys to touch, and 40 hours after birth girls look longer at a face than boys, while boys look longer at a suspended mechanical mobile.
– At four months old, if babies are frightened in a strange room, twice as many girls as boys cry.
– At 12, 18 or 24 months, girls look at dolls much more than boys, while boys look at cars much more than girls. It is hard to attribute these basic differences at such young ages to purely social influences.
– The development of the brain leads to many other differences and it has been claimed that clear sex differences exist in every brain lobe. There are some visible structural differences, such as a cluster of cells in the hypothalamus that is believed to relate to sexual behaviour and which is twice as big in men as in women. Evolution has selected differences between men and women so as to make their reproduction as successful as possible, which is its overriding aim.
– Small boys often get erections after the age of about seven, and by puberty more than half of all males will have tried to masturbate. It is only when girls reach puberty that they may begin to do so.
– About half of men think about sex every day or several times a day, which fits with my own experience, while only 20 per cent of women think about sex equally often.
– Men are far more likely to be sexually promiscuous, a throwback to evolution where procreation was all-important. The need for a more emotional attachment found in women must also have an evolutionary basis.
– Men are more likely to have an orgasm when sex includes vaginal intercourse, while many women are more likely to experience it when they engage in a variety of activities such as oral stimulation
– Hard-wired into the male brain, after millions of years of evolution, is a desire for sex in response to the sight of a good-looking young woman. In contrast, both male and female erotica cause sexual arousal in women, whether heterosexual or lesbian.
– A recent worldwide survey showed that visual stimuli play a much greater role in male sexual behaviour than in that of women, who value status, ambition or wealth more highly.
– Women show their emotions more than men and are more facially expressive for both positive and negative feelings.
– A major difference between the emotions of men and women lies in the expression of aggression, for which men enjoy a pronounced physical advantage. It has an evolutionary origin related to hunting and protection. This matters, as men have discriminated against women and dominated them in all societies from the earliest known times. Women can be aggressive but their aggression tends to be less physical. But girls and women with congenital adrenal hyperplasia (CAH), which increases testosterone in the womb, are more like males, with an increase in physical aggression.
– Almost the opposite of aggression is empathy, an emotion that marks a fundamental difference between the two sexes, being much stronger in women.
– Simon Baron-Cohen’s theory is that the female brain is predominantly hard-wired for empathy, while the male brain is predominantly hard-wired for systemising, that is, for understanding and building systems. So, for example, it is claimed that a systemiser will probably choose to read about computers, technology or science, whereas an empathiser will choose romance or fashion. Significantly, boys born with an insensitivity to testosterone are worse at systemising, and girls born with CAH have enhanced systemising capability and lower empathy.
– Other emotional differences are that women generally report greater disgust than men, especially sexual disgust, and men engage in more risky behaviour.
– As regards humour, according to Prof Robert Provine, professor of psychology at the University of Maryland, Baltimore, “Females are the leading laughers, but males are the best laugh getters.”
– A surprising finding is that distinctive words, syntax, colloquialisms, repetition and other features of written text can expose the gender of an author. An analysis of 14,000 text files from 70 separate studies found that, while men referred more to the properties of objects and impersonal topics, women used more words related to psychological and social topics.
– The areas in the brain where men and women generate their intelligence differ significantly. Men excel at mental rotation, where a subject is asked to compare two three-dimensional objects or shapes, and say if they are the same or mirror images, while females struggle. Women do better on precision manual tasks involving fine motor co-ordination, such the assembly of circuit boards in a factory, which may be a result of foraging skills that evolved long ago.
– Women perform better than men, on average, in tasks related to declarative memory, the retrieval of long-term memories of specific events and facts, and on tests of object-location memory. They are thus better at remembering family history and where they left the car keys.
– Many illnesses are strongly genetically associated with one or the other sex. Those that are more common in women include certain mental illnesses such as depression, eating disorders such as anorexia and bulimia, panic attacks and phobias. Also more common in women are autoimmune diseases such as multiple sclerosis and rheumatoid arthritis, chronic fatigue syndrome and osteoporosis.
– Very few autoimmune disorders show a male predominance. Males suffer more physical illnesses such as heart attacks and stroke. Other diseases more common in men include neurological disorders such as Parkinson’s disease, autism, attention deficit syndrome, dyslexia and addictions such as alcohol and drug abuse.
– Women live longer than men but only by an average of about four years.