High mating effort and antisocial and delinquent behaviors are closely linked. Some delinquent behaviors may honestly signal genetic quality. Men who exhibit high mating effort and who have high genetic quality would be expected to engage in more sexual coercion than other men because its costs to them are lowered by female preferences for them as sexual partners.

This commentary focuses on the omission of genetic and environmental variation in several competing evolved motive dispositions that not only react to different environmental contexts but also result in people structuring contexts to obtain psychological rewards. Cross-cultural research is poor evidence for alternate strategies because natural selection may operate to produce geographical variation in dispositional tendencies. Finally, I defend a traditional concept of plasticity in opposition to the alternate strategies concept of flexibility.

Preference for partners with low fluctuating asymmetry (FA) may produce “good gene” benefits. However, Gangestad & Simpson's analysis does not exclude immediate benefits of fertility. Low FA is related to fertility in men and women. Short-term changes in FA are correlated with fertility in women. It is not known whether temporal fluctuations in the FA of men are related to short-term fertility status.

No doubt all our behavior is the result of evolution, but I express skepticism about the validity of detailed arguments that purport to explain in detail how or why this occurred historically.

Prior to agriculture, human societies were small, with little variation for good genes sexual selection (GGSS) to work on. Across cultures, variation in paternal care makes the benefits of GGSS highly variable. Despite these caveats, female preferences for traits like male body symmetry suggest one reason for female short-term mating is gene shopping.

Human behavior can be analyzed using game theory models. Complex games may involve different rules for different players and may allow players to change identity (and therefore, rules) according to complex contingencies. From this perspective, mating behaviors can be viewed as strategic “plays” in a complex “mating game,” with players varying tactics in response to changes in the game's payoff matrix.

Women's mating strategies have typically been characterised as restrictive or coy. However, recent research on sociosexual behaviour suggests that the frequency of women's extra-pair copulations is a function of an unrestricted personality. While agreeing with the general thrust of Gangestad & Simpson's strategic pluralism theory we suggest that it is more likely a matter of finely calculated reproductive opportunism.

The worldwide variation in mating strategies can be explained by differential paternal investment theory, which traces the differences back to the climates where the various peoples (races) evolved. Male provisioning is necessary for women and children to survive cold winters, which is less essential for tropical women. Androstenone may be the substance that makes symmetrical men smell better to fertile females.

Although we find Gangestad & Simpson's argument intriguing, we question some of its underlying assumptions, including: (1) that fluctuating asymmetry (FA) is consistently heritable; (2) that symmetry is driving the effects; (3) that use of parametric tests with FA is appropriate; and (4) that a short-term mating strategy produces more offspring than a long-term strategy.

Gangestad & Simpson provide a persuasive argument that both men and women have evolved conditional mating strategies. Their references to “ancestral” males and females are rather vague, which is unfortunate, as they seek to justify their arguments by invoking human evolutionary history. When one actually examines the evidence for human evolution further, more support for their arguments can be found, as predominant types of mating strategies are likely to have shifted in light of environmental and anatomical developments. We can also see in the archaeological record evidence for a further dimension of strategic pluralism – the use of material culture to advertise good genes in some species of ancestral males.

Studies of fluctuating asymmetry (FA) in relation to sexual strategies in humans provide the empirical basis for many arguments in support of good genes sexual selection theory. Many FA studies, however, are flawed by bias in experimental design, inconsistent statistical analysis, and the sloppy handling of data.

Fluctuating asymmetry is more a signal of genetic fitness than a marker observable only to the researcher. Hence, it has to be demonstrated that low FA is an honest signal of genetic quality; this has not been demonstrated in Gangestad & Simpson's otherwise useful review.

Women's preference for symmetrical men need not have evolved as part of a good gene sexual selection (GGSS) reproductive strategy employed during recent human evolutionary history. It may be a remnant of the reproductive strategy of a perhaps promiscuous species which existed prior to the divergence of the human line from that of the bonobo and chimp.

Gangestad & Simpson present an idealized model of human mate strategies based on rational economics and genetics that elides most social constraints on human sexuality. They do not deal with observable complexities of courtship nor with ambiguities in short- and long-term mating. The model successfully explicates a narrow set of premises, but cannot yet explain complex sexual behavior.

Human males are more polygamously inclined than females. However, there is substantial within-sex variation in polygamous inclinations and practices. This is acknowledged by Gangestad & Simpson but we pose the question: Is the target article's “strategic pluralism” pluralistic enough? In addition, we argue that the hypothesis that the female orgasm is an adaptation for post-copulatory female choice between rival ejaculates demands more research.

Analyses of between-sex differences have provided a powerful starting point for evolutionarily informed work on human sexuality. This early work set the stage for an evolutionary analysis of within-sex differences in human sexuality. A comprehensive theory of human sexual strategies must address both between-sex differences and within-sex differences in evolved psychology and manifest behavior.

Women with high sociosexual orientation inventory (SOI) scores may trade signs of willingness to invest for signs of ability to invest, instead of, or in addition to, genetic benefits. The target person's status traits affect women's judgments of sexual/physical attractiveness more than men's. An objective measure of a physical trait such as FA is therefore crucial in untangling the factors affecting women's judgments of attractiveness.

Gangestad & Simpson make a convincing case for male and female psychological access to sexual strategies that dispose us towards both faithful long-term mating and promiscuity – according to socio- ecological conditions. However, their model fails to acknowledge how the human self-system's mediation of conduct can permit us to override voluntarily the pseudo-imperatives of optimizing inclusive fitness.

Not all of the studies cited in the target article as evidence that fluctuating asymmetry (FA) predicts male mating success demonstrate that the observed asymmetry is, in fact, FA. FA is a population-level pattern of differences between sides. Unless the population-level distributional criteria of bilateral traits are reported, the meaning of asymmetry in individuals is unknown.

This response reinforces several major themes in our target article: (a) the importance of sex-specific, within-sex variation in mating tactics; (b) the relevance of optimality thinking to understanding that variation; (c) the significance of special design for reconstructing evolutionary history; (d) the replicated findings that women's mating preferences vary across their menstrual cycle in ways revealing special design; and (e) the importance of applying market phenomena to understand the complex dynamics of mating. We also elaborate on three points: (1) Men who have indicators of genetic fitness may provide more direct benefits when female demand for extra-pair and short-term sex is very low; (2) both men and women track ecological cues to make mating decisions; and (3) more research on female orgasm is needed.