Despite a staggering body of research demonstrating sex differences in expressed emotion, very few theoretical models (evolutionary or non-evolutionary) offer a critical examination of the adaptive nature of such differences. From the perspective of a socio-relational framework, emotive behaviors evolved to promote the attraction and aversion of different types of relationships by advertising the two most parsimonious properties of reciprocity potential, or perceived attractiveness as a prospective social partner. These are the individual's (a) perceived capacity or ability to provide expedient resources, or to inflict immediate harm onto others, and their (b) perceived trustworthiness or probability of actually reciprocating altruism (Vigil 2007). Depending on the unique social demands and relational constraints that each sex evolved, individuals should be sensitive to advertise “capacity” and “trustworthiness” cues through selective displays of dominant versus submissive and masculine versus feminine emotive behaviors, respectively. In this article, I introduce the basic theoretical assumptions and hypotheses of the framework, and show how the models provide a solid scaffold with which to begin to interpret common sex differences in the emotional development literature. I conclude by describing how the framework can be used to predict condition-based and situation-based variation in affect and other forms of expressive behaviors.

From an evolutionary standpoint, a default presumption is that true beliefs are adaptive and misbeliefs maladaptive. But if humans are biologically engineered to appraise the world accurately and to form true beliefs, how are we to explain the routine exceptions to this rule? How can we account for mistaken beliefs, bizarre delusions, and instances of self-deception? We explore this question in some detail. We begin by articulating a distinction between two general types of misbelief: those resulting from a breakdown in the normal functioning of the belief formation system (e.g., delusions) and those arising in the normal course of that system's operations (e.g., beliefs based on incomplete or inaccurate information). The former are instances of biological dysfunction or pathology, reflecting “culpable” limitations of evolutionary design. Although the latter category includes undesirable (but tolerable) by-products of “forgivably” limited design, our quarry is a contentious subclass of this category: misbeliefs best conceived as design features. Such misbeliefs, unlike occasional lucky falsehoods, would have been systematically adaptive in the evolutionary past. Such misbeliefs, furthermore, would not be reducible to judicious – but doxastically1 noncommittal – action policies. Finally, such misbeliefs would have been adaptive in themselves, constituting more than mere by-products of adaptively biased misbelief-producing systems. We explore a range of potential candidates for evolved misbelief, and conclude that, of those surveyed, only positive illusions meet our criteria.

Four different accounts of the relationship between third-person mindreading and first-person metacognition are compared and evaluated. While three of them endorse the existence of introspection for propositional attitudes, the fourth (defended here) claims that our knowledge of our own attitudes results from turning our mindreading capacities upon ourselves. Section 1 of this target article introduces the four accounts. Section 2 develops the “mindreading is prior” model in more detail, showing how it predicts introspection for perceptual and quasi-perceptual (e.g., imagistic) mental events while claiming that metacognitive access to our own attitudes always results from swift unconscious self-interpretation. This section also considers the model's relationship to the expression of attitudes in speech. Section 3 argues that the commonsense belief in the existence of introspection should be given no weight. Section 4 argues briefly that data from childhood development are of no help in resolving this debate. Section 5 considers the evolutionary claims to which the different accounts are committed, and argues that the three introspective views make predictions that are not borne out by the data. Section 6 examines the extensive evidence that people often confabulate when self-attributing attitudes. Section 7 considers “two systems” accounts of human thinking and reasoning, arguing that although there are introspectable events within System 2, there are no introspectable attitudes. Section 8 examines alleged evidence of “unsymbolized thinking”. Section 9 considers the claim that schizophrenia exhibits a dissociation between mindreading and metacognition. Finally, section 10 evaluates the claim that autism presents a dissociation in the opposite direction, of metacognition without mindreading.

This target article presents an integrated evolutionary model of the development of attachment and human reproductive strategies. It is argued that sex differences in attachment emerge in middle childhood, have adaptive significance in both children and adults, and are part of sex-specific life history strategies. Early psychosocial stress and insecure attachment act as cues of environmental risk, and tend to switch development towards reproductive strategies favoring current reproduction and higher mating effort. However, due to sex differences in life history trade-offs between mating and parenting, insecure males tend to adopt avoidant strategies, whereas insecure females tend to adopt anxious/ambivalent strategies, which maximize investment from kin and mates. Females are expected to shift to avoidant patterns when environmental risk is more severe. Avoidant and ambivalent attachment patterns also have different adaptive values for boys and girls, in the context of same-sex competition in the peer group: in particular, the competitive and aggressive traits related to avoidant attachment can be favored as a status-seeking strategy for males. Finally, adrenarche is proposed as the endocrine mechanism underlying the reorganization of attachment in middle childhood, and the implications for the relationship between attachment and sexual development are explored. Sex differences in the development of attachment can be fruitfully integrated within the broader framework of adaptive plasticity in life history strategies, thus contributing to a coherent evolutionary theory of human development.

I argue that the magnitude and nature of sex differences in aggression, their development, causation, and variability, can be better explained by sexual selection than by the alternative biosocial version of social role theory. Thus, sex differences in physical aggression increase with the degree of risk, occur early in life, peak in young adulthood, and are likely to be mediated by greater male impulsiveness, and greater female fear of physical danger. Male variability in physical aggression is consistent with an alternative life history perspective, and context-dependent variability with responses to reproductive competition, although some variability follows the internal and external influences of social roles. Other sex differences, in variance in reproductive output, threat displays, size and strength, maturation rates, and mortality and conception rates, all indicate that male aggression is part of a sexually selected adaptive complex. Physical aggression between partners can be explained using different evolutionary principles, arising from the conflicts of interest between males and females entering a reproductive alliance, combined with variability following differences in societal gender roles. In this case, social roles are particularly important since they enable both the relatively equality in physical aggression between partners from Western nations, and the considerable cross-national variability, to be explained.

We agree with Archer that human sex differences in aggression are well explained by sexual selection, but note that “social learning” explanations of human behaviors are not logically mutually exclusive from “evolutionary” explanations and therefore should not be framed as such. We discuss why this type of framing hinders the development of both social learning and evolutionary theories of human behavior.

Evolutionary models of behavior often encounter resistance due to an apparent focus on themes of sex, selfishness, and gender differences. The target article might seem ripe for such criticism. However, life history theory suggests that these themes, and their counterparts, including cooperation, generosity, and gender similarities, represent two sides of the same coin – all are consequences of reproductive trade-offs made throughout development.

Positive and negative misbeliefs both may have evolved to serve important adaptive functions. Here, we focus on the role of negative misbeliefs in promoting adaptive outcomes within the contexts of romantic relationships and intergroup interactions. Believing bad things can paradoxically encourage romantic fidelity, personal safety, competitive success, and group solidarity, among other positive outcomes.

This commentary suggests an alternate definition for metacognition, as well as an alternate basis for the “aboutness” relation in representation. These together open the way for an understanding of mindreading that is significantly different from the one advocated by Carruthers.

We suggest that the framework proposed by Vigil is useful in laboratory contexts but might come up short for in vivo social interactions. Emotions result from cost-benefits trade-offs but are not solely generated at the individual level to establish emotional social spheres. In organizational contexts, emotion expression can be a constitutive part of a professional activity, and observed sex differences might vanish.

The radical evolutionary step that divides human decision-making from that of nonhumans is the ability to excite the reward process for its own sake, in imagination. Combined with hyperbolic over-valuation of the present, this ability is a potential threat to both the individual's long term survival and the natural selection of high intelligence. Human belief is intrinsically “unfounded” or under-founded, which may or may not be adaptive.

In middle childhood, boys show more avoidant attachments and girls more ambivalent attachments as a prelude to gender differentiation in reproductive strategies. However, we have failed to find systematic and method-independent gender differences in middle or late childhood attachments, nor in adult attachment representations. We conclude that Del Giudice's model rests on a brittle empirical basis.

Carruthers claims that “our knowledge of our own attitudes results from turning our mindreading capacities upon ourselves” (target article, Abstract). This may be true in many cases. But like other constructivist claims, it fails to explain occasions when constructed knowledge is accurate, like a well-supported scientific theory. People can know their surrounding world and to some extent themselves. Accurate self-knowledge is firmly established for both somatosensory and social pain.

Archer provides seemingly compelling evidence for his claim that sexual selection explains sex differences in human aggression better than social role theory. I challenge Archer's interpretation of some of this evidence. I argue that the same evidence could be used to support the claim that what has been selected for is the ability to curb aggression and discuss implications for Archer's theory.

Emotion expression serves functions in exploitative resource-acquisition strategies that may not include relationship reciprocity. These include rendering victims more exploitable and signaling one's status as non-exploitable. A comprehensive theory of emotion expressions must explain their role in adaptations for exploitation, as well as evolved defenses against those pursuing a strategy of exploitation.

Biofeedback mechanisms (a) between individuals, (b) between the individual and the society structures which shape individual cognitions, and (c) within the individual genetic biochemical circulation, may explain the diversity of trustworthiness potential and the option of mutual trust for every individual in any given society.

Archer presents a traditional view of intrasexual competition. Knowledge of a species' social structure provides a more complete picture. Human males compete against individuals with whom they may cooperate later in inter-group aggression. By contrast, females compete against individuals for a mate's continued support. Females' aggression may aim at eliminating the competition, whereas males simply may attempt to dominate others.

In this commentary, we attempt to broaden thinking and dialogue about how our ancestral past might have affected attachment and reproductive strategies. We highlight the theoretical benefits of formulating specific predictions of how different sources of stress might impact attachment and reproductive strategies differently, and we integrate some of these ideas with another recent evolutionary model of human mating.

Naive physics beliefs can be systematically mistaken. They provide a useful test-bed because they are common, and also because their existence must rely on some adaptive advantage, within a given context. In the second part of the commentary we also ask questions about when a whole family of misbeliefs should be considered together as a single phenomenon.

Carruthers argues that an integrated faculty of metarepresentation evolved for mindreading and was later exapted for metacognition. A more consistent application of his approach would regard metarepresentation in mindreading with the same skeptical rigor, concluding that the “faculty” may have been entirely exapted. Given this result, the usefulness of Carruthers' line-drawing exercise is called into question.