Fatness and scarcity revisited
Via Dienekes: Ember and colleagues (2005) address the question of whether cultural preferences for fatness or thinness in women are related to the prevalance of resource scarcity in a society. The hypothesis that these should be related comes from the work of Brown and Konner (1987). From the current paper:
In most cultures, the ideal female form is not thin. According to Brown and Konner (1987), 81% of societies in a Human Relations Area Files (HRAF) sample preferred plump or moderately fat women, and 90% preferred large or fat hips and legs. (Few anthropological reports discuss preferred male body types.) Brown and Konner suggest that plumpness is generally adaptive because fat stores allowpeople to survive periods of scarcity, as well as being associated with earlier menarche, successful pregnancies, and adequate lactation. But if this be so, why is thinness valued in some cultures (even some preindustrial ones)? At the least, one might expect that these will be cultures with little resource scarcity, and a study by Anderson, Crawford, Nadeau, and Lindberg (1992) supported this hypothesis. However, the research reported here does not (Ember et al. 2005:258).
In other words, the hypothesis is that people should recognize that fatness is adaptive to resource scarcity and should shape their cultural preferences accordingly. A fairly glaring weakness in the hypothesis is its failure to explain a preferences for thinness in many societies, which has no simple economic explanation.
The study finds a relatively strong negative correlation (on the order of -0.5) between valuation of fatness and three measures of scarcity. This contradicts the hypothesis that these should be positively related.
Ember et al. (2005:261-262) discuss the influence of food storage potential on these relationships:
Food storage is not significantly related either to the valuation of fatness in women or to any of our three measures of resource scarcity, but it does modulate their relationships to one another. In societies with little or no storage (score 1), high threat of disasters significantly predicts low valuation of fatness (in our combined samples, q= .56, P=.02, two tails, N=17), as we found in Sample 1, but in societies with some storage (scores 2Ð3), threat of disasters has no relationship to the valuation of fatness in women.
From their negative finding, Ember and colleagues (2005) consider several alternatives, ranging from the idea that thinness may help in some way, to the idea that groups may be selected on the basis of their total energy consumption, to the idea that male preferences are driven by their desire to dominate or control their mates. All of these are found wanting, although the most time is spent on the last.
This is a case where it is unclear how much a correlation can tell you. A relatively strong correlation of around 0.5 or so still explains only a quarter of the variance. In this case, the predicted variable is cultural preference, which means that even a significant correlation with scarcity still leaves many other factors to account for the preference.
And in this case, the "preference" consists of a score based on a few ethnographic interviews. How do individuals within a society vary in their preferences? How extensive is the overlap among societies in the range of variation? To test evolutionary strategies, this is the level of detail that is really necessary, but the available data simply aren't there. So there may be no point to considering the matter further, beyond saying that the "value" that societies place on fat women does not appear to reflect the pragmatic concerns of surviving resource scarcity or famine.
I would suggest an additional hypothesis, one that also focuses on the evolutionary importance of fatness, but in a different way. Fat women (and men) tend to have fat sons (and daughters). In a highly mobile society where running, hunting, competition with other people, or other traits are highly important to survival (and thereby highly valued), men will prefer mates that can give them healthy, fit, and competitive sons. This hypothesis has little to do with people's ability to predict who will survive a famine (which fatness may help a little with, but is not determinative) and much to do with their ability to understand simple heritability.
It is especially applicable to societies who keep domesticated animals, since these people not only have to survive shortfalls themselves, but also have to get their stock through them. And furthermore, fat stock are better tasting and better energy sources (both for meat and milk). If people can breed their animals with eye toward increasing their fatness, they can surely figure out that a fat wife will have similar famine-resisting properties. Thus, a cultural difference in mate preference as opposed to livestock breeding practices would be a clear sign that some other factor is judged more important in mating than famine survival value. My hypothesis is offspring qualities. This hypothesis might also be testable on the basis of other observable qualities, such as intelligence, personality, and facial proportions.
Ember et al. (2005:266) end their paper with a discussion of changing female fatness preferences in the United States:
In the United States, shifts towards valuing thinness versus fatness seem to have coincided with the rise of women's movements in the 1920s and late 1960s. Consider that Marilyn Monroe epitomized beauty in the 1950s; she was well-rounded, not thin. "Thin" became more popular when people (particularly women) began to question early marriage and staying home to be mothers of large families. They appear to have rejected male chivalry and preferred men who were sensitive and caring. (Dennis Werner, personal communication, suggested this argument.) Was machismo behavior also less acceptable at those times? We suggest that it was, particularly among intellectuals and the elite. Whether and how these changes are causally connected require further investigation.
This seems like a roundabout way of saying that style equals success. Are human biologists studying attractiveness missing the nose on the face of the issue?
References:
Brown, PJ and Konner M. 1987. An anthropological perspective on obesity. Ann New York Acad Sci 499:29-46.
Ember CR, Ember M, Korotayev A, de Munck, V. 2005. Valuing thinness or fatness in women: reevaluating the effect of resource scarcity. Evol Hum Behav 2:257-270. ScienceDirect
John Hawks Department of Anthropology
University of Wisconsin—Madison
Copyright © 2007 John Hawks