To explain financial and prosocial biases toward attractive adults, Maestripieri et al. defend a “strategic mating behavior” account. Their central argument relies on a causal relationship between viewing attractive individuals (A); a host of cognitive, emotional, and physiological changes (B); and financial/social generosity or other desirable behaviors (C). Yet, their reasoning is based on data from a collection of different experimental studies, and one cannot reliably determine how much (if any) of the effect of A (e.g., attractiveness) on C (e.g., financial decision) is actually explained by B (e.g., testosterone). Their review therefore provides no definitive evidence that mating motives or their proxies (e.g., physiological changes) are the actual causes of an attractiveness bias. There are in fact theoretical reasons to doubt the accuracy of a causal effect. This comment will focus on the idea that strategic mating behavior does not generally imply that favors should increase with attractiveness: a phenomenon we label the out-of-my-league effect.

The target article's argumentation is grounded on a mating model in which only the benefits of mating with attractive people are considered. This completely overlooks the effect of the probability of success in mating: A simple model of courtship behavior should take into account not only the benefit of mating with an attractive individual, but also the probability of doing so – itself determined by the mating opportunities of others. The potential “court maker,” if motivated solely by mating per se as hypothesized, faces a trade-off between the benefit of mating and the probability of success: Whereas the former increases, the latter realistically decreases with the attractiveness of the target. For a given attractiveness of the court maker, attractiveness-based matching implies that the probability of success decreases with the attractiveness of the potential mate, as the target's opportunities are likewise based on attractiveness. If the probability of success decreases more steeply than the benefit of mating increases given the potential mate's attractiveness, then the more attractive the potential mate, the lower is the expected benefit of a match, that is, the benefit of a match weighted by its probability of occurrence. The out-of-my-league hypothesis states that one should not spend resources to court a very attractive potential mate with a minimal probability of success, but rather prefer a moderately attractive one with a reasonable chance of success. In a nutshell: To mate or not to mate is not the question, but rather with whom.

In fact, at the population level, “smart” courtship behavior is more likely to lead, on average, to a bias toward average-looking individuals: If the distribution of attractiveness is concentrated around its mean (such as in a normal distribution, for example), individuals will most likely favor moderately rather than highly attractive mates. In terms of strategy, the average court-making agent is better off targeting individuals of intermediate attractiveness. Not only is it the rational strategy, but also it is the fittest one from an evolutionary standpoint: An individual systematically favoring much more attractive individuals than herself is less likely to mate, and this behavioral pattern is more likely to disappear from the population by evolutionary pressure. This explains the opportunity costs associated with trying to mate with very attractive individuals, which is largely excluded from the analysis by Maestripieri et al.

In other words, there is no guarantee that the relationship between the level of effort by the courter will be monotonic with the attractiveness of the potential mate; quite the reverse may occur, because positive assortative matching implies that “birds of a feather flock together” (McPherson et al. Reference McPherson, Smith-Lovin and Cook2001). The courtship explanation, implicitly based on an endogenous matching model, thus has implications at odds with the set of empirical facts it aims to explain. A complete model of endogenous mating is needed to understand the evolutionary explanation. Such a model has to account not only for the effect of attractiveness on individuals’ decision making (as does the target article), but also for the general equilibrium implications of such mating behaviors that are distortions in the probability that mating is actually achieved given the relative attractiveness of the partners.

Because mating motives do not necessarily explain the attractiveness bias, it appears premature to reject economic and social psychological explanations. Indeed, the main argument for favoring a mating-based over a stereotype-based account relies on a gender moderation of the attractiveness bias. However, such moderation can be easily explained, for example, from a social psychological perspective. The opposite-sex beauty premium effect could simply reflect stereotypic processes. Although the authors reject these based on the fact that an attractiveness bias occurs even when controlling for personality traits and independently from stereotype-induced expectations, the stereotype content must be distinguished from its accuracy and actualization in reality (Judd & Park Reference Judd and Park1993). Furthermore, as stereotypes operate most of the time on an unconscious level and their influence cannot be captured through explicit self-reports, the reviewed evidence is not a valid rebuttal of a stereotype-based explanation. Moreover, the same-sex negative bias could reflect self-threat because of comparisons and/or competition with attractive individuals. A possible self-threat regulation strategy (among others) relies on derogation and destructive behaviors toward attractive individuals. Such counterproductive responses to threatening comparisons occur routinely in the workplace (Lam et al. Reference Lam, Van der Vegt, Walter and Huang2011). To protect their work environment from negative comparisons, individuals can even provide poor hiring recommendations (Garcia et al. Reference Garcia, Song and Tesser2010). Crucially, the attractiveness gender bias appears only for individuals who are sensitive to negative comparisons, whereas the rest show a gender-independent attractiveness bias (Agthe et al. Reference Agthe, Spörrle, Frey and Maner2014).

Although the “strategic mating behavior” account in the target article is scientifically attractive, we shed light on a theoretical argument that goes against their preferred explanation. As the out-of-my-league demonstration suggests: “One's man meat is another man's poison.”