There is nothing mysterious about the use of stimulant drugs. They tap into our brain chemistry in ways that make us feel good. The crux is that long-term use produces seriously disabling health consequences.
The Problem for Adaptationists
People continue to smoke at the expense of survival, vigor, and reproductive success. Why? Clearly, because it is an addiction. While smokers may effectively choose the addiction by choosing to use the drug initially, they develop health problems not because they choose to smoke, but because they are nicotine addicts.
Why do people smoke and become addicted? One plausible answer is that the pleasurable effects are immediate whereas the health consequences are delayed in time and get discounted (if they are known).
According to some scholars, including anthropologist Donald Symons (1), the fact that people voluntarily engage in such damaging habits as smoking means that looking for adaptive explanations for people's behavior in modern societies is a fool's errand.
One might point to many other examples of maladaptive behavior. The widespread use of contraception with falling birth rates, and declining populations, in developed countries illustrates humans doing exactly the opposite of maximizing reproduction.
The smoking problem may not be so intractable to an adaptationist approach as Symons thinks. Instead of restricting the analysis to a single generation, one must consider a longer time frame.
People acquire contradictory information about smoking over time (2). At first, it is a pleasurable stimulant that is associated with relaxation, leisure, happiness, success, and the good life, as depicted in movies of the 1950s in the U.S. featuring stars such as Humphrey Bogart and Marlon Brando.
During that period, tobacco companies conspired to bury scientific research establishing the strong link between smoking and lung cancer. Once the scientific evidence became widely known, there was a steep fall in smoking rates that continues to this day (2).
A Possible Solution
In the face of sharply declining sales in the developed world, tobacco companies redoubled their marketing efforts in developing countries where smoking rates, and sales, are rising.
Although the relevant scientific information is now freely available, poorly-educated people often discount such information as irrelevant to them.
When the science is borne out by personal experience, people take it seriously. This often involves the loss of a parent, family member, or friend, to smoking-related illness. So adapting to the adverse health effects of smoking may take several generations and this is likely to be more drawn out in poor countries where residents have minimal understanding of the scientific evidence.
In developed countries, sales are declining sharply thanks to greater awareness of the scientific link between smoking and cancer that is borne out both in anti-smoking health messages and by personal contact with victims of smoking-related diseases (2).
Contrary to Symon's assertion that human behavior in modern societies is hopelessly maladaptive, a more nuanced conclusion is appropriate.
Health-damaging tobacco addiction is far less problematic to an adaptive perspective than might be imagined.
Smoking in Adaptive Perspective
New users experience nicotine as a mildly pleasant stimulant that taps into the brain's evolved neurochemistry. So the widespread adoption of tobacco by indigenous people when they are exposed to it by foreigners is not surprising.
Residents of poor countries are not only less informed about the link between cigarette smoking and cancer. They also live their lives in the present and are less concerned about the distant future (3).
Once people become fully informed about the link between smoking and cancer, smoking rates do decline (2)
So the rapid adoption of smoking by Americans following the widespread availability of cigarettes early in the 20th century entered an abrupt reversal from the 1970s on (4).
The decline occurred despite a distressing tendency for some young people to adopt smoking as a sign of adolescent rebellion.
Just as the adoption of smoking was a multi-generational phenomenon, so too the decline in tobacco use is a protracted process. Some changes in social behavior can take several generations to play out, whether it is the emancipation of female sexuality and careers, the assimilation of immigrants, or the adoption and subsequent rejection, of smoking.
The decline in smoking helps people to lead longer, healthier, lives so that it is adaptive in Darwinian terms. The mere fact that it occurs by learning and experience does not make it any the less adaptive. Indeed, gene selection is just one factor in the adaptation of humans, and other species, to changing environments.
Gene selection cannot account for curious shifts in supposedly species-typical behavior, such as moose not being frightened of wolves after these are reintroduced to their habitat (5). So it is clearly not required for human adaptation to modern conditions, including adjustment to altered perceptions about smoking.
1 Symons, D. (1992). On the use and misuse of Darwinism in the study of human behavior. Adaptiveness and adaptation. Ethology and Sociobiology, 11, 427-444.
2 Barber, N. (2015). Why behavior matches ecology: Adaptive variation as a novel approach. Cross-Cultural Research, 49, 57-89.
3 Clark, G. (2007). A farewell to alms: A brief economic history of the world. Princeton, NJ: Princeton University Press.
4 Cummings, K. M., Brown, A., & O’Connor, R. (2007). The cigarette controversy. Cancer Epidemiology Biomarkers and Prevention, 16, 1070-1076.
5 Berger, J., Swenson, J. E., & Persson, I. L. (2001). Recolonizing carnivores and naïve prey: Conservation lessons from Pleistocene extinctions. Science, 291, 1036-1039