Men are responsible for 86% of all indictable crimes in England and Wales, 88% of crimes against the person, 90% of murders, and 98% of sexual offences (all for the year 2012).
Testosterone is one of the factors but it is just one of the chemical messengers that make men more risk taking and aggressive. The real question is why did men evolve to be more risk taking and aggressive in the first place?
There is an (incorrect) assumption that the behaviour and insecurities of men and women is received solely via “socialisation” i.e. an interaction with their environment. For example a male preoccupation with aggression and risk taking is “caused” by being exposed to other male role models. This incorrect assumption is based on flawed and discredited social “science” research that fails to correct for genetics.
1. We are a disposable container that has evolved to ensure genes get moved forward in time. We die. They don’t. Any behaviour conferred by the genes on a species, which increases the likelihood of having more offspring, will ensure more of those genes are passed to the next generation.
2. Evolution takes a long time. One tick of the evolutionary clock takes about 250,000 years. i.e. we are virtually identical to our ancestors from 50,000 years ago.
Our male and female ancestors have had very different evolutionary pressure over the previous millions of years.
Human females have a pathetic ability to reproduce, having no more than a dozen pregnancies in their lifetime. Each pregnancy is life threatening and she will generally only produce offspring one at a time. Their fertility declines sharply at 35 and falls off a cliff at 40. Human children are unusually vulnerable in infancy and take many years to reach maturity. Women therefore engage in a long, energy sapping and life threatening investment in their children to ensure these (few) offspring reach childbearing age. She must choose her mate with great care to ensure her offspring receive beneficial genes from the father, which in turn maximises the chance of her own genes prospering in the next generation. It also means she must carefully and selflessly look after the few offspring she manages to produce. She (i.e. her genes) has no other choice. So she evolved to be nurturing.
Human males produce 250,000 sperm every second and their number of offspring is limited only by their opportunity to impregnate willing (or unwilling) females. They are fertile their whole life. Two strategies would work to increase the number of their genes in the next generation. 1. Look after their offspring, nurture them and ensure they reach child bearing age (i.e. copy the only strategy available to women). 2. Spread their sperm as far and wide as possible, have thousands of offspring and hope that some reach childbearing age. A third alternative is the best. Do both. Men invest almost nothing in child rearing so it makes sense for them to take huge risks to have the opportunity to reproduce.
It is also worth pointing out why men are so disposable in evolutionary terms, whilst at the same time being more valuable for getting large numbers of genes in subsequent generations if they are very successful and / or out-survive other men. A population of 100 women and one man has a good chance of survival. A population of 100 men and one woman is probably doomed. If men kill off their competitors (in a good war for example) the population can survive and the surviving men’s genes will massively prosper. If women are killed off their genes won’t prosper due to their very limited ability to reproduce. Evolution of genes explains why men will be more risk-taking, aggressive and competitive. Evolution of genes explains why women are dramatically less aggressive. It’s not in her genes’ interests if the whole population dies out. This also explains why men and women are more likely to put men in harms way and feel more protective towards women (reference: Moral Chivalry).
Women will choose high social status men (a proxy for him having good genes) to ensure their own genes have a good chance of survival in future generations. To prove high social status takes a bit longer so women tend to go for successful, older men (4 years older in the UK on average).
Men are programmed to advertise their success and achievements in order to attract a high social status mate. It is worth taking risks to achieve this status because the genetic rewards can be enormous. For example about 8% of the men in a large region of Asia have Genghis Khan’s Y chromosome. He clearly had many willing and unwilling sexual partners but took great risk to achieve this.
Men will choose young, healthy, fertile (“attractive”) women because their chosen mate primarily needs to be fit to survive 9 months of pregnancy and the years of childcare that follows. Men have evolved to visually select a mate on this basis. Women have evolved for millions of years with this pressure. Women are therefore programmed to try to look young and attractive in order to find a suitable mate. Much of this behaviour is hard wired, as is our sexuality and our urge to have sex with attractive members of the opposite sex.
I’m describing the is not the ought of human behaviour, and nothing here should make us believe we can predict the behaviour of individual men and women. But please remember evolution is about survival of our genes and does not care one jot about human happiness, fairness or equality.
But to put the male of our species in context here are two relevant facts:
1. Men commit most of the crimes.
2. Few men commit crimes.
Actually we men evolved into a social, altruistic species, with a few violent exceptions.
Also whilst men commit most of the crimes, they are also its main victims: