The Austrian ethologist, Konrad Lorenz, noted the surprising role of aggressive instincts in binding social animals together. One of the basic structural features that all such species display is a prevalence of peacemaking behaviours. The possibility of violent conflict is frequently thwarted by the use of friendly gestures that pacify and placate aggressive urges. In fact, it seems that animals which are incapable of attacking their own kind never find the occasion to be friends. The territorial instincts of aggression (which can be tied to testosterone – both in men and women) seems to be a necessary precondition for friendship in animals of all kinds.
Lorenz's protégé, Irenäus Eibl-Eibesfeldt, noted that this was only part of the story, however. Aggression can strengthen the bond between animals, such as when the leader of a pack of chimpanzees drives away a predator and strengthens the unity of the pack in the process, but the bond must first exist before it can be strengthened. Eibl-Eibesfeldt noted that only those species that care for their offspring in an intimate and personal fashion display such bonds at all. Caring for the young is perhaps the only context in which such a connection could be forged, since the role of parent requires an extended and reliable state of affection. The parental instinct (which can be tied to the chemical oxytocin) seems to be the foundation of society among mammals and birds.
This reveals an interesting and unexpected influence of gender in the story of how life came to rediscover social living after becoming far too complex to be merely programmed to get along (like an ant colony and or the co-operating polyps in a Portuguese Man O'War). Oestrogen, the female sex hormone, is essential to the effect of oxytocin in encouraging bonds to form – such as the parental bond, or the pair bond between animals who mate for life. Like testosterone, oestrogen is present in both men and women to differing degrees – and the instincts these chemicals support are vital to social behaviour. Thus the sex hormones also underpin the instincts holding society together. The family is truly the microcosm for society, even among non-human animals; social life is an alliance of the sexes.
Part 7 of 23 in the Pentenary series.