Gender differences in violence are a function of brain neurotransmitters

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It could be argued,  I suppose,  that women are not « really » more docile than men.  It could be argued that women are acculturated into docility,  doing themselves violence by forcing themselves, and being forced, into docility, against their true nature.   Here is the evidence to the effect that men are « really » more violent than women because of endogenous differences in their brains.   Dopamine seems to be more concentrated and more active in men’s than in women’s brains (though there are some local exceptions).   Brain serotonin, on the other hand, seems to be less present in men than in women. The same pattern of sex differences is observed in monkeys, dogs, wolves, rats, birds and fish (Augustinovich, 1992; Saudou et al, 1994). Wild versions of animals (wolves, buffalo) have the human male pattern whereas domestic versions of the same species (dogs, cattle) have the female human pattern. Artificial selection of these species (breeding) had the obvious objective (among other things) of producing strains that could adapt to domestic life.  Breeders certainly selected animals which were docile around humans.   By having them mate with similar animals,  the breeders ended up fixing in successive generations those genes responsible for the desired behavioral and physical traits.  And it seems extremely likely that the genes in question influence synthesis of selective neurotransmitters.  Serotonin-deficient animals are more aggressive than their normal counterparts (Sluyter et al, 1996).   Pro-serotonin and antidopaminergic manipulations have a pacifying effect in various species studied so far (Arregui  et al, 1993; Bernhardt, 1997; Pant et Nath, 1993).    Homicide victims are often people with records of violent crime.   One can confidently suppose that they are more aggressive than people who die of more natural causes.   Brains of homicide victims have been intensively studied.   They are generally deficient in serotonin and overly endowed in dopamine (Ohmori, Arora & Meltzer, 1992).   Extremely aggressive men, psychopathic criminals, have an exacerbation of the male-typical pattern.    A recent epidemiological study investigated a very large cohort of 781 normal men and women with regard to whole blood serotonin and violence.   A highly significant relation was found between high serotonin levels (which the authors assume to correspond to low  brain levels) and violent behavior,  in men.   Another recent study even found that post menopausal women with lower serotonin levels manifested more impulsivity and hostility than women with higher levels of serotonin.   This finding was not found in pre menopausal women presumable because the menstrual cycle made women too « variable » to yield a reliable correlation (Manuck et al, 1998).