Triggers in our environment can thus “activate the fast life genes,” as Kaufman puts it, and by making the fast-life behaviors rewarding and pleasurable, evolution ensures that we pursue them doggedly, up to and including Kiedis’ sex-heroin marathons. A number of environmental factors can serve as triggers, including several quite relevant to the life histories of many well-known musicians. For example, having a father who hasn’t invested much in caring for his children increases the likelihood that boys will live a fast life of delinquency and aggression, and that girls will employ shorter-term mating strategies (having learned not to count on men as long-term providers).

In general men, whose minimal investment in offspring has been set much lower by evolution than women’s, are also more likely to adopt higher-risk, fast-life mating strategies, Catherine Salmon, a professor of psychology at the University of Redlands, tells OZY. But women are perhaps the most important aspect of the male environment — a man’s behavior is typically only as good (or bad) as his options. “How much fooling around men do depends on how willing women are,” says Salmon. “If there are lots of women available and willing to have sex, then men are not going to say no, for the most part.”

And most male rock stars do not make a habit of refusing their many female admirers. Nor would many of the rest of us if placed in their spandex and shoes. “Given the particular temptations that go along with that lifestyle,” says Salmon, “there are relatively few individuals who would not engage in it when given the opportunity, especially when it’s given to you as a young male.”