We present behavioral lateralizations of spiders and ants and their probable survival value. They clearly conform to the vertebrate lateralizations reviewed by Vallortigara & Rogers (V&R) and to earlier arthropod studies. We suggest two complementary reviews: (1) differences in lesion susceptibility and muscle strength between left and right body side, and (2) perceptual biases and predator inspection in invertebrates.

Although statistically significant correlations have been found among political, economic, and social indices, on the one hand, and measures of sociosexuality, on the other, it is likely that these correlations are second-order effects. Underpinning the reproductive freedom associated with higher sociosexuality are factors more closely related to biology, namely, easy access to safe, effective contraception and reproductive medical care.

The target article, which is part of a larger study, the International Sexuality Description Project (ISDP), seeks to explore cross-culturally aspects of human mating behavior on a global scale. However the nonrepresentation of large cultures restricts the depth of this study. The inferences drawn from such a sample must therefore remain limited despite the impressive sample sizes. In a larger context it raises thoughts on how partial disclosures may misrepresent the design of the larger study.

Operational sex ratio (OSR) is the correct sex ratio measure for predicting sociosexuality, but it is unclear whether this is the measure used. It would be valuable to know how OSR and sociosexuality correlate separately for males and females. The relationship between sociosexuality and OSR should also be examined with OSR measured at the local level of the mating market, where sex ratio must be having its psychological effects.

if language is crucial to the development of shared colour categories, how might cultural constraints influence the development of divergent category sets? we propose that communities arrive at different sets of categories because the tendency to group by perceptual similarity interacts with environmental factors (differential access to dying and printing technologies), to make different systems optimal for communication in different situations.

Evolutionary psychologists should go beyond research on individual differences in attitudes and focus more on detailed models of psychological mechanisms. We argue for complementing attitude research with agent-based computational modeling of mate choice. Agent-based models require detailed specification of individual choice mechanisms that can be evaluated in terms of both their psychological plausibility and the population-level outcomes they produce.

Across mammals, when fathers matter, as they did for hunter-gatherers, sex-similar pair-bonding mechanisms evolve. Attachment fertility theory can explain Schmitt's and other findings as resulting from a system of mechanisms affording pair-bonding in which promiscuous seeking is part. Departures from hunter-gatherer environments (e.g., early menarche, delayed marriage) can alter dating trajectories, thereby impacting mating outside of pair-bonds.

Natural selection of asymmetric traits operates at multiple levels. Some asymmetric traits (like having a dominant eye) are tied to more universal aspects of the environment and are coded genetically, while others (like pedestrian turning biases) are tied to more ephemeral patterns and are largely learned. Species-wide trends of asymmetry can be better modeled when different levels of natural selection are specified.

a common objection to utilitarianism is that it clashes with our common moral intuitions. understanding the role that heuristics play in moral judgments undermines this objection. it also indicates why we should not use john rawls' model of reflective equilibrium as the basis for testing normative moral theories.

although there are some common underlying mechanisms for many nonhuman behavioural asymmetries, the evidence at present is not compelling for commonalities in cerebral organisation across vertebrates. phylogenetic analysis of detour behaviour in fish suggests that more closely related species are not particularly similar in the direction of turning; contingency and demands of ecological niches may better explain such asymmetries.

On the basis of a reinterpretation of the International Sexuality Description Project (ISDP) data, we suggest that findings are consistent with the view that human reproductive behaviour is largely under social control. Behaviours associated with a high Sociosexual Orientation Index (SOI) may be part of a progressive change in reproductive behaviour initiated by the dispersal of kin that occurs as societies modernize.

by emphasizing that color categories are the collective achievement of a language community, the methodology of steels & belpaeme (s&b) suggests a number of corollaries. it focuses attention on whether a system of categories is optimized to match color experience. if a hypothesis can be operationalized about the nature of the optimality – about how color language becomes standardized – it becomes testable.

Although the search for universal human traits is necessarily the principle focus of researchers in evolutionary psychology, the habitual reliance on undergraduate students introduces profound doubts concerning resulting data. Furthermore, the absence of relevant data from foraging societies undermines claims of cross-cultural universality in this paper and in many others.

crossing the border into the moral domain changes moral thinking in two ways: (1) the facts at hand become “anthropocentric” facts not easily open to revision, and (2) moral reasoning is often the servant of moral intuitions, making it difficult for people to challenge their own intuitions. sunstein's argument is sound, but policy makers are likely to resist.

Shortcomings in the target article preclude adequate tests of developmental/attachment and strategic pluralism theories. Methodological problems include comparing college student attitudes with societal level indicators that may not reflect life conditions of college students. We show, through two principal components analyses, that multiple tests of the theories reduce to only two findings that cannot be interpreted as solid support for evolutionary hypotheses.

In this commentary, I consider Schmitt's cross-cultural investigation of sociosexuality from a comparative perspective. I argue that such a perspective lends support to an evolutionary explanation of a number of Schmitt's findings, including universal sex differences in sociosexuality and the sensitivity of mating behavior to contextual variables such as sex ratio.

The Sociosexual Orientation Inventory (SOI) was not designed to illuminate the sexually dimorphic mental mechanisms posited by evolutionary theories. Its results are therefore open to competing interpretations. Measures designed to tap the thought processes surrounding sexual experience generate findings that are more compatible with evolutionary than with social structural theory.

the heuristics-and-biases approach requires a clear separation of normative and descriptive models. normative models cannot be justified by intuition, or by consensus. the lack of consensus on normative theory is a problem for prescriptive approaches. one solution to the prescriptive problem is to argue contingently: if you are concerned about consequences, here is a way to make them better.

with respect to human color categories, steels & belpaeme's (s&b's) simulations over-emphasize the possible influence of language. in humans, color processing is the result of a long evolutionary process in which categories developed without language. common principles of color processing lead to similar color categories, but interindividual variation in color categories exists. even color-deficiencies, causing large differences in color categories, remain inconspicuous in everyday life, thereby contradicting the hypothesis that language could play a role in color category formation.

Simpson and Gangestad's (1991) Sociosexual Orientation Inventory (SOI) is pivotal in Schmitt's cross-national study on sociosexuality. Here I elaborate on psychometric shortcomings of the SOI that are crucial in this research context.