The fact that men who get married start displaying less competitive abilities, as compared to the period before the marriage, is very interesting. These observations mainly concern sport competitions, but are, to a certain degree, also valid for arts, science, social activism, creativity and even criminality.
Scientists consider that the social and professional affirmation represents a way of displaying the masculine potential of a man and is intended to attract women; however, as soon as a man gets married, his necessity of a competitive consumption also reduces, leading to a more moderate behavior [Kanazawa, 2003; Griskevicius et al., 2006; Nettle, Clegg, 2006; Farrelly, Nettle, 2007].
Marriage also has a robust effect on the rate of violent manifestations (implicitly the criminal ones) in men who have a predisposition towards delinquency; the rate of married men who are involved in criminal acts is lower by 35% than that of unmarried men from the same risk category [Sampson et al., 2006].
The decreasing of competitional motivation is closely linked with the level of testosterone. It has been found that the level of testosterone is about 20% lower in men who are involved in a romantic relationship than in those who are not [Burnham et al., 2003]. Also, it is important the duration of the relationship. If we are talking about a fresh relationship (less than 12 months), then man’s level of testosterone is not very different from that of single men. But if the relationship lasts more than a year (it is said, in this case, than the man has found his match), the level of testosterone in man’s body drops [Farrelly et al., 2015].
The level of testosterone is even lower in men who have become fathers; they don’t have the same urge to „show off” in front of women, being now guided by other types of behavior strategies [Gray et al., 2002, 2006]. It is interesting the fact that hormonal changes in men’s bodies occur even before the baby is born, during the period when their wives are still pregnant; already at that point the drop in the level of testosterone is considerable [Edelstein et al., 2014].
As soon as a man becomes a parent, there are also important changes that occur in the biochemical aspects of his brain (these changes also occur in the brains of homosexuals that have adopted a child). A growth of grey matter in the amygdala, striatum, hypothalamus and lateral prefrontal cortex; and a decrease in the orbitofrontal and posterior cingulate cortex take place.
Therefore, neurological changes take place overall; due to them, young fathers become more and more emphatic, more sensitive towards the emotions of their baby and more forgiving. Scientists believe that, in this way, the brain gets ready for the upcoming tight emotional relationship between the father and the child [Kim et al., 2014].
It is obvious that on such a hormonal and neurological background the degree of aggressiveness in men is reduced. The marriage and the parenthood have, no doubt, a peace-making effect on men, rendering them calmer. Then “middle age crisis” starts, but that’s another story…
© Dorian Furtună, ethologist
Photo: Father and son / Flickr / https://www.flickr.com/photos/en321/8109445120/
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