Many have interpreted symbolic material culture in the deep past as evidencing the origins sophisticated, modern cognition. Scholars from across the behavioural and cognitive sciences, including linguists, psychologists, philosophers, neuroscientists, primatologists, archaeologists, and palaeoanthropologists have used such artefacts to assess the capacities of extinct human species, and to set benchmarks, milestones, or otherwise chart the course of human cognitive evolution. To better calibrate our expectations, the present paper instead explores the material culture of three contemporary African forager groups. Results show that, although these groups are unequivocally behaviourally modern, they would leave scant long-lasting evidence of symbolic behaviour. Artefact sets are typically small, perhaps as a consequence of residential mobility. When traded materials are excluded, few artefacts have components with moderate–to–strong taphonomic signatures. The present analyses show that artefact function influences preservation probability, such that utilitarian tools for the processing of materials and the preparation of food are disproportionately likely to contain archaeologically traceable components. There are substantial differences in material use among populations, which create important population-level variation in preservation probability, independent of cognitive differences. I discuss the factors – cultural, ecological, and practical – that influence material choice. In so doing, I highlight the difficulties of using past material culture as an evolutionary or cognitive yardstick.

We agree with Rendell and Whitehead that cetaceans acquire knowledge from caretakers and peers, and that a clear understanding of this process can provide insight into the evolution of mammalian cognition. The passive observational methods they advocate, however, are inadequate for determining what cetaceans know. Only by experimentally investigating the cognition of cetaceans can we hope to understand what they learn through social interactions.

Understanding the relationship between gesture, sign, and speech offers a valuable tool for investigating how language emerges from a nonlinguistic state. We propose that the focus on linguistic status is problematic, and a shift to focus on the processes that shape these systems serves to explain the relationship between them and contributes to the central question of how language evolves.

Although Barsalou is right in identifying the importance of perceptual symbols as a means of carrying certain kinds of content, he is wrong in playing down the inferential resources available to amodal symbols. I argue that the case for perceptual symbol systems amounts to a false dichotomy and that it is feasible to help oneself to both kinds of content as extreme ends on a content continuum. The continuum thesis I advance argues for the inferential content at one end and perceptual content at the other. In between the extremes, symbols might have aspects that are either perceptual or propositional-linguistic in character. I argue that this way of characterising the issue preserves the good sense of Barsalou's recognition of perceptual representations and yet avoids the tendency to minimise the gains won with symbolic representations vital to contemporary cognitive science.

Building a theory on extant species, as Ackermann et al. do, is a useful contribution to the field of language evolution. Here, I add another living model that might be of interest: human language ontogeny in the first year of life. A better knowledge of this phase might help in understanding two more topics among the “several building blocks of a comprehensive theory of the evolution of spoken language” indicated in their conclusion by Ackermann et al., that is, the foundation of the co-evolution of linguistic motor skills with the auditory skills underlying speech perception, and the possible phylogenetic interactions of protospeech production with referential capabilities.

According to Roberts, self-experimentation is a viable tool for idea generation in the behavioral sciences. Here we discuss some limitations of this assertion, as well as particular design and data-analytic shortcomings of his experiments.

Depue & Collins [D&C] propose a well-conceived and nicely detailed theory of the involvement of dopaminergic connections in extraversion. Since these systems are hypothesized to be associated with reward sensitivity, other neural systems that are involved with reward sensitivity should be considered as well. In this commentary it is argued that there is now enough evidence for the involvement of the left and right frontal regions of the brain in approach and withdrawal behavior that it should also be considered in theories of personality such as D&C's. Integration of predominantly subcortical and cortical theories of personality/brain function may produce a more comprehensive picture of temperament and personality.

We present arguments that the analogy between humans and social insects is coincidental, rather than based upon real similarities. In their claims, Gowdy & Krall largely omit the role of institutions in the formation of complex societies, warfare, and regulation. They also offer no strong explanation for the expansion of agriculture despite its early detrimental effects except the “mistake hypothesis” (cf. Diamond 1987).

The seemingly puzzling datum that behavior decreases after punishing stimulation while individuals are still able to remember traumatic episodes is discussed in relation to dopaminergic and noradrenergic neuromodulation. The described mechanisms may contribute to an understanding of how occurrences of learning reconsolidation yield different outcomes across intra- and extra-therapeutic settings.

Koriat and Goldsmith clearly show the need for an alternative to the storehouse metaphor; however, the alternative metaphor they choose – the correspondence metaphor – is problematic. A more suitable one is the capacity metaphor.

Psychological science can benefit from a theoretical unification with other social sciences. Social psychology in particular has gone through cycles of repression, denying itself the opportunity to see the calculating element in human interaction. A closer alignment with theories of evolution and theories of interpersonal (and intergroup) games would bring strategic reasoning back into the focus of research.