Testosterone

This is a highly readable history of a crucial hormone that still has a powerful effect in our time. Subtitled 'sex, power and the will to win', the book is a wide-ranging study by a Cambridge neuroscientist. It becomes clear that testosterone is not only important for sexual selection and survival, but also has important social implications and is indeed constrained by many social norms. It causes men not only to grow features enhancing their sexual attractiveness, but also hones their competitive and risk-taking skills. Reading the book makes one more self-aware of its impact. On the wider front, testosterone is related to aggression and war, including rape, especially in war. This represents a breakdown in social norms, which one also sees in gangs. Naturally, young men feel its effects more strongly, especially when combined with the kind of peer pressure that also establishes identity.

Herbert discusses the rather different manifestation of testosterone in financial traders, remarking that unbridled behaviour of any sort is incompatible with a stable and functional society. In young men, the impact of testosterone also seems to be associated with the development of fanaticism. Similarly to the implications of Paul Mclean's triune brain, it is useful to realise that 'humans bring with them ancestral baggage in the form of basic brain mechanisms for sex, aggression, and other behaviours that represent their evolutionary history and have been essential for the success, but are now modulated by more recently developed parts of the brain and the demands of a very different social and physical environment.' We certainly need the drive and energy associated with testosterone, but equally we need to remain alert to the most appropriate types of its social management.