Testosterone's connection to sex differences and key evolutionary processes arouses controversy. Effects on humans and other species, though, are not robotically deterministic but are parts of complex interactions. We discuss the societal implications of these findings and consider how the naturalistic fallacy and the person–situation dichotomy contribute to misunderstandings here.

Mazur & Booth provide life scientists with an example of the multilevel biopsychosocial approach. Research paradigms have to become more flexible and multidisciplinary if we are to free ourselves from the nature–nurture dichotomy that we have long agreed was simplistic and shortsighted. I point out a variety of kinds of interactions that may be the next frontier for behavioral scientists.

Aggressiveness is a vital component of dominating behavior. We must distinguish adaptive from nonadaptive aggression and must control for skills, intelligence, appropriate context variables, and – most important – whether the aggression displayed was actually suitable for improving a subject's social status. If we do, we may find a consistent positive correlation between adaptive aggressiveness and testosterone.

Mazur & Booth present an intriguing model of the relationship between circulating testosterone levels and dominance behaviour in man, but their review of studies on testosterone–behaviour relationships in man is selective. Much of the evidence they cite is correlational in nature. Placebo-controlled manipulations of testosterone levels are required to test their hypothesis that dominance levels are testosterone-dependent in man. The changes in testosterone level that follow behavioural experience may be a consequence of stress. Testosterone levels in man are determined by a wide variety of factors, and a multivariate approach is required.

Four aspects of Mazur & Booth's target article are discussed from a comparative perspective using teleost fish as a reference: (a) the relationship between aggression, dominance, and androgens; (b) the interpretation of the data in light of the challenge hypothesis; (c) the potential role of testosterone as a physiological mediator between social status and the expression of male characters; and (d) the fact that metabolic conversions of testosterone may be important in its effect on aggression/ dominance.

Evidence from many species suggests that social, developmental, and cognitive variables are important influences on aggression. Few direct activational or organizational effects of hormones on aggression and dominance are found in nonhuman primates. Female aggression and dominance are relatively frequent and occur with low testosterone levels. Social, cultural, and developmental mechanisms have more important influences on dominance and aggression than hormones.

Tests of models of reciprocal interactions of testosterone and behaviour patterns in honour subcultures, if based on adult samples measured at a single point in time, would be aided by measures of behaviour in such samples that indirectly index basal testosterone levels at earlier developmental ages, for example, hand preference and other measures of cerebral dominance. Such models raise questions about the social preconditions of honour subcultures, and their indirect effects on health.

Men's interest in sex partners' status traits and commitment (investment thoughts) declines with number of sex partners and permissiveness of attitudes; women's investment thoughts do not seem to decline. Testosterone, dominance, sexual attractiveness, and number of sex partners are correlated in men but not in women. It is plausible that these sex differences are part of sexually dimorphic feedback systems. This type of feedback is consistent with both reciprocal and basal models of testosterone.

This Response focuses on the strength of the testosterone (T) dominance relationship, the circumstances under which aggression accompanies dominance, the viability of the basal model, mediators and moderators of the T-dominance relationship, and the research that is needed.

Talents that selectively facilitate the acquisition of high levels of skill are said to be present in some children but not others. The evidence for this includes biological correlates of specific abilities, certain rare abilities in autistic savants, and the seemingly spontaneous emergence of exceptional abilities in young children, but there is also contrary evidence indicating an absence of early precursors of high skill levels. An analysis of positive and negative evidence and arguments suggests that differences in early experiences, preferences, opportunities, habits, training, and practice are the real determinants of excellence.

Experiential factors such as long-term deliberate practice are powerful and necessary conditions for outstanding achievement. Nevertheless, to be able to reject the role of biology based individual differences (including genetic ones) in the manifestation of talent requires designs that expose heterogeneous samples to so-called testing-the-limits conditions, allowing asymptotic levels of performance to be analyzed comparatively. When such research has been conducted, as in the field of lifespan cognition, individual differences, including biology based ones, come to the fore and demonstrate that the orchestration of excellence requires joint attention to genetic–biological and experiential factors.

Howe et al. suggest that most talents can be explained in terms of practice and other environmental effects, and only exceptionally by innate factors. This commentary provides an illustration of one such exception: performance on the Embedded Figures Test by people with autism and their relatives.

We present a theoretical model and corresponding research design (Bronfenbrenner & Ceci 1994) that could yield stronger evidence for (or perhaps against) Howe et al.'s conclusions. The model assesses levels of heritability (h²) under different amounts of training and practice, thus providing estimates of the independent contribution of “innate talent” to the quality of development outcomes. The design can also reveal the extent to which this independent contribution varies systematically as a function of other influential factors identified by Howe et al.

Investigations of innate talent should narrow the definition of talent to deal with constituent abilities, identify touchstone phenomena, and provide detailed explanations of these phenomena. A list of relevant phenomena is proposed.

Clear evidence of large individual differences in children's performance in talent areas can be explained either in terms of innate gifts (the “talent account”) or in terms of early exposure (the “no talent account” proposed by Howe et al.). At this point, there is no conclusive support for either account, and it is doubtful that talent could be explained exclusively by only one of them.

The position advocated in the target article should be called “absurd environmentalism.” Literature showing that general intelligence is related to musical ability is not cited. Also ignored is the heritability of musical talent. Retrospective studies supporting practice over talent are incapable of showing differences in talent, because subjects are self-selected on talent. Reasons for the popularity of absurd environmentalism are discussed.

The emphasis on innate talent as the basis for outstanding achievement underestimates the importance of hard work. Learned industriousness helps supply the sustained effort required for superior achievement. The goal of having a productive, well-educated citizenry can be furthered by rewarding students for high effort and attending carefully to their individual educational needs.

To make genuine progress toward explicating the relation between innate talent and high levels of ability, we need to consider the differences in structure between most everyday abilities and expert performance. Only in expert performance is it possible to show consistently that individuals can acquire skills to circumvent and modify basic characteristics (talent).

The existence of natural talent becomes easier to see at extremes in performance. Practice alone could not account for the differences in performance that exist at the highest levels. Practice and other factors are no doubt important contributors to outstanding performance, but not enough to explain great creative works. Talent is essential.

Evidence shows that outstanding talent is more than the product of determined effort by people of much the same inborn ability. Indications of inborn individual differences come from very early studies of childhood. No randomly selected child has ever reached world-class achievement by practice alone, which, though essential, cannot itself produce greatness.