Despite the ontogenetic allometric size effects that explain much of phyletic variation in brain components, the residuals of some structures indicates that mosaic brain evolution was an important factor in hominid evolution, and that reorganization of the hominid brain may have occurred as early as 3+ MY. Finlay et al.'s allometric technique masks residual variation around allometric trends, and the patterns of residuals relevant to species-specific departures from strict allometric trends.

Although we agree that a constructivist approach to emotional experience makes sense, we propose that implicit (visceromotor and somatomotor) emotional processes are dissociable from explicit (attention and reflection) emotional processes, and that the conscious experience of emotion requires an integration of the two. Assessments of implicit emotion and emotional awareness can be helpful in the neuroscientific investigation of emotion.

This commentary criticizes nonverbal methods of assessing theory-of-mind on the basis of prior training of the critical response because they would encourage simple, nonmentalistic, associative solutions even in subjects with mentalistic capacities. I propose instead a new experimental paradigm based upon the use of spontaneous responses in less artificial situations. This method has already provided positive evidence of some level of ToM understanding in nonhuman primates.

While some species have affiliative and even cooperative interactions between individuals of different social groups, humans are alone in having durable, positive-sum, interdependent relationships across unrelated social groups. Our capacity to have harmonious relationships that cross group boundaries is an important aspect of our species' success, allowing for the exchange of ideas, materials, and ultimately enabling cumulative cultural evolution. Knowledge about the conditions required for peaceful intergroup relationships is critical for understanding the success of our species and building a more peaceful world. How do humans create harmonious relationships across group boundaries and when did this capacity emerge in the human lineage? Answering these questions involves considering the costs and benefits of intergroup cooperation and aggression, for oneself, one's group, and one's neighbor. Taking a game theoretical perspective provides new insights into the difficulties of removing the threat of war and reveals an ironic logic to peace – the factors that enable peace also facilitate the increased scale and destructiveness of conflict. In what follows, I explore the conditions required for peace, why they are so difficult to achieve, and when we expect peace to have emerged in the human lineage. I argue that intergroup cooperation was an important component of human relationships and a selective force in our species history beginning at least 300 thousand years. But the preconditions for peace only emerged in the past 100 thousand years and likely coexisted with intermittent intergroup violence which would have also been an important and selective force in our species' history.

We address points of confusion pertaining to interrelations among and roles of core constructs involved in the production of performance outcomes. We do so informed by the body of work derived from Brehm's seminal motivation intensity theory – in particular an elaboration from the theory concerned with fatigue influence on effort and associated cardiovascular responses in people confronted with performance challenges.

We report an experiment that unambiguously shows an effect of full-form frequency for fully regular Dutch inflected verbs falling into Clahsen's “default” category, negating Clahsen's claim that regular complex words in the default category are not stored.

Traditional lay perceptions of genetics are plagued with essentialist biases leading to some unfortunate consequences. Changes in the scientific understanding of heredity in general, and in genotype–phenotype relationships more specifically, provide a vital basis for shifting public understanding of genetics. Facilitating postgenomic literacy among the public has the potential to have translational implications in diminishing deleterious attitudes, beliefs, and behaviors.

This commentary draws connections between technological culture emergence and recent trends in using assistive technology to reduce the burden of Alzheimer's disease. By the technical-reasoning hypothesis, cognitively-impaired individuals will lack the cognitive ability to employ technologies. By the technological reserve hypothesis, social-motivational and cultural transmissibility factors can provide foundations for using technology as cognitive prosthetics even during neurodegenerative illnesses.

In discussing the effects of grandparents on child survival in natural fertility populations, Coall & Hertwig (C&H) rely extensively on the review by Sear and Mace (2008). We conducted a more detailed summary of the same literature and found that the evidence in favor of beneficial associations between grandparenting and child survival is generally weak or absent. The present state of the data on human alloparenting supports a more restricted use of the term “cooperative breeding.” Human stem family situations with celibate helpers-at-the-nest can be described as cooperatively breeding, but the term is a poor fit to many human family systems.

The commentaries on our target article, “Psychosis and Autism as Diametrical Disorders of the Social Brain,” reflect the multidisciplinary yet highly fragmented state of current studies of human social cognition. Progress in our understanding of the human social brain must come from studies that integrate across diverse analytic levels, using conceptual frameworks grounded in evolutionary biology.

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.