Modularity, comparative cognition and human uniqueness

Studying the Development of Navigation Using Virtual Environments

Research on spatial navigation is essential to understanding how mobile species adapt to their environments. Such research increasingly uses virtual environments (VEs) because, although VE has drawbacks, it allows for standardization of procedures, precision in measuring behaviors, ease in introducing variation, and cross-investigator comparability. Developmental researchers have used a wide range of VE testing methods, including desktop computers, gaming consoles, virtual reality, and phone applications. We survey the paradigms to guide researchers' choices, organizing them by their characteristics using a framework proposed by Girard (2022) in which navigation is reactive or deliberative, and may be tied to sensory input or not. This organization highlights what representations each paradigm indicates. VE tools have enriched our picture of the development of navigation, but much research remains to be done, e.g., determining retest reliability, comparing performance on different paradigms, validating performance against real-world behavior and open sharing. Reliable and valid assessments available on open-science repositories are essential for work on the development of navigation, its neural bases, and its implications for other cognitive domains.

Among-individual differences in auditory and physical cognitive abilities in zebra finches

Among-individual variation in performance on cognitive tasks is ubiquitous across species that have been examined, and understanding the evolution of cognitive abilities requires investigating among-individual variation because natural selection acts on individual differences. However, relatively little is known about the extent to which individual differences in cognition are determined by domain-specific compared with domain-general cognitive abilities. We examined individual differences in learning speed of zebra finches across seven different tasks to determine the extent of domain-specific versus domain-general learning abilities, as well as the relationship between learning speed and learning generalization. Thirty-two zebra finches completed a foraging board experiment that included visual and structural discriminations, and then these same birds went through an acoustic operant discrimination experiment that required discriminating between different natural categories of acoustic stimuli. We found evidence of domain-general learning abilities as birds' relative performance on the seven learning tasks was weakly repeatable and a principal components analysis found a first principal component that explained 36% of the variance in performance across tasks with all tasks loading unidirectionally on this component. However, the few significant correlations between tasks and high repeatability within each experiment suggest the potential for domain-specific abilities. Learning speed did not influence an individual's ability to generalize learning. These results suggest that zebra finch performance across visual, structural, and auditory learning relies upon some common mechanism; some might call this evidence of "general intelligence"(g), but it is also possible that this finding is due to other noncognitive mechanisms such as motivation.

Preliminary evidence for one-trial social learning of vervet monkey alarm calling

How do non-human primates learn to use their alarm calls? Social learning is a promising candidate, but its role in the acquisition of meaning and call usage has not been studied systematically, neither during ontogeny nor in adulthood. To investigate the role of social learning in alarm call comprehension and use, we exposed groups of wild vervet monkeys to two unfamiliar animal models in the presence or absence of conspecific alarm calls. To assess the learning outcome of these experiences, we then presented the models for a second time to the same monkeys, but now without additional alarm call information. In subjects previously exposed in conjunction with alarm calls, we found heightened predator inspection compared to control subjects exposed without alarm calls, indicating one-trial social learning of 'meaning'. Moreover, some juveniles (but not adults) produced the same alarm calls they heard during the initial exposure whereas the authenticity of the models had an additional effect. Our experiment provides preliminary evidence that, in non-human primates, call meaning can be acquired by one-trail social learning but that subject age and core knowledge about predators additionally moderate the acquisition of novel call-referent associations.

Preliminary evidence for one-trial social learning of vervet monkey alarm calling

How do non-human primates learn to use their alarm calls? Social learning is a promising candidate, but its role in the acquisition of meaning and call usage has not been studied systematically, neither during ontogeny nor in adulthood. To investigate the role of social learning in alarm call comprehension and use, we exposed groups of wild vervet monkeys to two unfamiliar animal models in the presence or absence of conspecific alarm calls. To assess the learning outcome of these experiences, we then presented the models for a second time to the same monkeys, but now without additional alarm call information. In subjects previously exposed in conjunction with alarm calls, we found heightened predator inspection compared to control subjects exposed without alarm calls, indicating one-trial social learning of 'meaning'. Moreover, some juveniles (but not adults) produced the same alarm calls they heard during the initial exposure whereas the authenticity of the models had an additional effect. Our experiment provides preliminary evidence that, in non-human primates, call meaning can be acquired by one-trail social learning but that subject age and core knowledge about predators additionally moderate the acquisition of novel call-referent associations.

Intergroup conflict: origins, dynamics and consequences across taxa

Although uniquely destructive and wasteful, intergroup conflict and warfare are not confined to humans. They are seen across a range of group-living species, from social insects, fishes and birds to mammals, including nonhuman primates. With its unique collection of theory, research and review contributions from biology, anthropology and economics, this theme issue provides novel insights into intergroup conflict across taxa. Here, we introduce and organize this theme issue on the origins and consequences of intergroup conflict. We provide a coherent framework by modelling intergroup conflicts as multi-level games of strategy in which individuals within groups cooperate to compete with (individuals in) other groups for scarce resources, such as territory, food, mating opportunities, power and influence. Within this framework, we identify cross-species mechanisms and consequences of (participating in) intergroup conflict. We conclude by highlighting crosscutting innovations in the study of intergroup conflict set forth by individual contributions. These include, among others, insights on how within-group heterogeneities and leadership relate to group conflict, how intergroup conflict shapes social organization and how climate change and environmental degradation transition intergroup relations from peaceful coexistence to violent conflict.

This article is part of the theme issue ‘Intergroup conflict across taxa’.

The structure of executive functions in preschool children and chimpanzees

Executive functions (EF) are a core aspect of cognition. Research with adult humans has produced evidence for unity and diversity in the structure of EF. Studies with preschoolers favour a 1-factor model, in which variation in EF tasks is best explained by a single underlying trait on which all EF tasks load. How EF are structured in nonhuman primates remains unknown. This study starts to fill this gap through a comparative, multi-trait multi-method test battery with preschoolers (N = 185) and chimpanzees (N = 55). The battery aimed at measuring working memory updating, inhibition, and attention shifting with three non-verbal tasks per function. For both species the correlations between tasks were low to moderate and not confined to tasks within the same putative function. Factor analyses produced some evidence for the unity of executive functions in both groups, in that our analyses revealed shared variance. However, we could not conclusively distinguish between 1-, 2- or 3-factor models. We discuss the implications of our findings with respect to the ecological validity of current psychometric research.

Curricula and Teaching Methodology in the Field of Health Education: What Do We Know so Far?

Health education is the interdisciplinary branch of pedagogy, medico-biological sciences, and health sciences, which addresses issues of prevention and the adoption of practices and strategies to reduce morbidity and mortality of the general population. Curricula are the subjects comprising a course of study in a school or college. The thematic axes of the Curricula of Health Education should include microbe transmission prevention, sexual and reproductive health, voluntary blood donation, oral health, smoking prevention, mental health promotion of children and adolescents, knowledge about sunlight, hygiene and vision protection, the value of old age, accident prevention, infection prevention (HIV, hepatitis etc.), healthy posture, healthy breathing, environmental health, healthy sleep, healthy diet, healthy exercise activities, problems involved in internet technology in adolescence, the role of play in childhood, and the prevention of addictions. Both behaviorism and constructivism are equally appropriate learning theories for teaching health education. The present paper aims to summarize all the available-to-date information on these issues.

Penetrabilidad cognitiva en la percepción visual temprana: Evidencia empírica en humanos

Con base en un trasfondo teórico sobre las concepciones modulares de la mente de Fodor (2001) y Pinker (2005), el objetivo del presente texto es analizar cualitativemente la solidez de la evidencia experimental de una muestra de artículos publicados entre 2002 y 2017 que apoyan la tesis de la penetrabilidad cognitiva en la percepción visual temprana. El estudio se justifica por las implicaciones que pueden tener los resultados de estas investigaciones para las diferentes concepciones sobre arquitectura mental en funciones perceptuales, procesamiento de la información intra e intermodular e isomorfismo entre arquitectura mental y cerebral. La metodología que se utilizó para realizar este estudio implicó establecimiento de la tesis y de los criterios de inclusión de los artículos a revisar, selección final de los artículos más representativos sobre las subáreas seleccionadas, análisis de la calidad metodológica y de los resultados de éstos, identificación de aportes específicos de cada estudio a la tesis planteada e interpretación y síntesis de los hallazgos. De 26 artículos revisados sobre el tema, se reportan y analizan 7, que se consideran representativos de 4 subáreas: penetrabilidad de expectativas, de percepción del color, de rasgos faciales y de reconocimiento de objetos. Se concluye que hay amplia y sólida evidencia convergente (perceptual y neurofisiológica) a favor de los fenómenos penetrativos en la visión temprana, lo cual apoyaría indirectamente la hipótesis de permeabilidad de los módulos mentales de Pinker. Se formulan recomendaciones sobre aspectos por investigar y variables a controlar en experimentos sobre este tema.

Computational animal welfare: towards cognitive architecture models of animal sentience, emotion and wellbeing

To understand animal wellbeing, we need to consider subjective phenomena and sentience. This is challenging, since these properties are private and cannot be observed directly. Certain motivations, emotions and related internal states can be inferred in animals through experiments that involve choice, learning, generalization and decision-making. Yet, even though there is significant progress in elucidating the neurobiology of human consciousness, animal consciousness is still a mystery. We propose that computational animal welfare science emerges at the intersection of animal behaviour, welfare and computational cognition. By using ideas from cognitive science, we develop a functional and generic definition of subjective phenomena as any process or state of the organism that exists from the first-person perspective and cannot be isolated from the animal subject. We then outline a general cognitive architecture to model simple forms of subjective processes and sentience. This includes evolutionary adaptation which contains top-down attention modulation, predictive processing and subjective simulation by re-entrant (recursive) computations. Thereafter, we show how this approach uses major characteristics of the subjective experience: elementary self-awareness, global workspace and qualia with unity and continuity. This provides a formal framework for process-based modelling of animal needs, subjective states, sentience and wellbeing.

Different mechanisms underlie implicit visual statistical learning in honey bees and humans

The ability of developing complex internal representations of the environment is considered a crucial antecedent to the emergence of humans' higher cognitive functions. Yet it is an open question whether there is any fundamental difference in how humans and other good visual learner species naturally encode aspects of novel visual scenes. Using the same modified visual statistical learning paradigm and multielement stimuli, we investigated how human adults and honey bees (Apis mellifera) encode spontaneously, without dedicated training, various statistical properties of novel visual scenes. We found that, similarly to humans, honey bees automatically develop a complex internal representation of their visual environment that evolves with accumulation of new evidence even without a targeted reinforcement. In particular, with more experience, they shift from being sensitive to statistics of only elemental features of the scenes to relying on co-occurrence frequencies of elements while losing their sensitivity to elemental frequencies, but they never encode automatically the predictivity of elements. In contrast, humans involuntarily develop an internal representation that includes single-element and co-occurrence statistics, as well as information about the predictivity between elements. Importantly, capturing human visual learning results requires a probabilistic chunk-learning model, whereas a simple fragment-based memory-trace model that counts occurrence summary statistics is sufficient to replicate honey bees' learning behavior. Thus, humans' sophisticated encoding of sensory stimuli that provides intrinsic sensitivity to predictive information might be one of the fundamental prerequisites of developing higher cognitive abilities.

Old and New Approaches to Animal Cognition: There Is Not "One Cognition"

Using the comparative approach, researchers draw inferences about the evolution of cognition. Psychologists have postulated several hypotheses to explain why certain species are cognitively more flexible than others, and these hypotheses assume that certain cognitive skills are linked together to create a generally "smart" species. However, empirical findings suggest that several animal species are highly specialized, showing exceptional skills in single cognitive domains while performing poorly in others. Although some cognitive skills may indeed overlap, we cannot a priori assume that they do across species. We argue that the term "cognition" has often been used by applying an anthropocentric viewpoint rather than a biocentric one. As a result, researchers tend to overrate cognitive skills that are human-like and assume that certain skills cluster together in other animals as they do in our own species. In this paper, we emphasize that specific physical and social environments create selection pressures that lead to the evolution of certain cognitive adaptations. Skills such as following the pointing gesture, tool-use, perspective-taking, or the ability to cooperate evolve independently from each other as a concrete result of specific selection pressures, and thus have appeared in distantly related species. Thus, there is not "one cognition". Our argument is founded upon traditional Darwinian thinking, which-although always at the forefront of biology-has sometimes been neglected in animal cognition research. In accordance with the biocentric approach, we advocate a broader empirical perspective as we are convinced that to better understand animal minds, comparative researchers should focus much more on questions and experiments that are ecologically valid. We should investigate nonhuman cognition for its own sake, not only in comparison to the human model.

A Critical Review of Behavioral and Emotional Disinhibition

The theory of "disinhibition" has been very influential in psychiatry and neurology for over a century. Disinhibition has been used to explain clinical findings in many neurological and psychiatric disorders including dementia, traumatic brain injury, attention deficit hyperactive disorder, substance abuse, impulsivity in personality disorders, and neurodevelopmental disorders. In addition, disinhibition has been used as a unifying theory to link clinical observations with cognitive findings, and even cellular findings. This review discusses the origins and history of the theory of disinhibition and its strengths and weaknesses in four domains: face validity, consistency with other brain mechanisms, consistency with evolutionary mechanisms, and empiric support. I assert that the vagueness of the theory, inconsistency with other brain mechanisms, and lack of empiric support limit the usefulness of this theory. Alternative approaches, based on findings in other motor, language, and cognitive functions, are discussed.

Kea show three signatures of domain-general statistical inference

One key aspect of domain-general thought is the ability to integrate information across different cognitive domains. Here, we tested whether kea (Nestor notabilis) can use relative quantities when predicting sampling outcomes, and then integrate both physical information about the presence of a barrier, and social information about the biased sampling of an experimenter, into their predictions. Our results show that kea exhibit three signatures of statistical inference, and therefore can integrate knowledge across different cognitive domains to flexibly adjust their predictions of sampling events. This result provides evidence that true statistical inference is found outside of the great apes, and that aspects of domain-general thinking can convergently evolve in brains with a highly different structure from primates. This has important implications not only for our understanding of how intelligence evolves, but also for research focused on how to create artificial domain-general thought processes.

Gains v. losses, or context dependence generated by confusion?

Tversky and Kahneman introduced the term framing for the finding that people give different answers to the same question depending on the way it is posed. One form of framing involves presenting the same outcome as either a gain or a loss. An experiment on starlings by Marsh and Kacelnik suggests that this form of framing occurs in non-humans. We argue that the experimental result demonstrates framing in the general sense of context dependence but does not provide compelling evidence of framing in terms of gains and losses. A version of scalar utility theory which is extended to include the possibility of memory errors accounts for the data and suggests future lines of research.

Towards a comparative science of emotion: Affect and consciousness in humans and animals

The componential view of human emotion recognises that affective states comprise conscious, behavioural, physiological, neural and cognitive elements. Although many animals display bodily and behavioural changes consistent with the occurrence of affective states similar to those seen in humans, the question of whether and in which species these are accompanied by conscious experiences remains controversial. Finding scientifically valid methods for investigating markers for the subjective component of affect in both humans and animals is central to developing a comparative understanding of the processes and mechanisms of affect and its evolution and distribution across taxonomic groups, to our understanding of animal welfare, and to the development of animal models of affective disorders. Here, contemporary evidence indicating potential markers of conscious processing in animals is reviewed, with a view to extending this search to include markers of conscious affective processing. We do this by combining animal-focused approaches with investigations of the components of conscious and non-conscious emotional processing in humans, and neuropsychological research into the structure and functions of conscious emotions.

Female cognitive performance and mass are correlated with different aspects of mate choice in the zebra finch (Taeniopygia guttata)

A female's cognitive ability may influence her mate preferences through various mechanisms. These mechanisms include the direct effect of cognitive ability on the information-processing skills used during mate choice, and the indirect effect of cognitive ability on quality when females mate assortatively. Here, we examined whether the ability to learn a novel foraging task, a cognitive skill which has been associated with reproductive success in other capacities, was correlated with song preferences in female zebra finches (Taeniopygia guttata). Female preferences were measured in an operant testing chamber where hops on a perch triggered song playback. Females were given the choice of (1) conspecific vs. heterospecific song and (2) high-quality male vs. low-quality male conspecific song. We found that female performance on the novel foraging task was positively correlated with preference for conspecific song, but not with preference for high-quality male song. Instead, female mass was positively correlated with preference for high-quality male song, potentially signifying that female mass is a stronger predictor of female quality in assortative mating than female cognitive performance. Female mass and cognitive performance were unrelated. Our results suggest that the particular traits of a female that affect conspecific preference do not necessarily affect preference for high-quality males.

Measuring and understanding individual differences in cognition

Individuals vary in their cognitive performance. While this variation forms the foundation of the study of human psychometrics, its broader importance is only recently being recognized. Explicitly acknowledging this individual variation found in both humans and non-human animals provides a novel opportunity to understand the mechanisms, development and evolution of cognition. The papers in this special issue highlight the growing emphasis on individual cognitive differences from fields as diverse as neurobiology, experimental psychology and evolutionary biology. Here, we synthesize this body of work. We consider the distinct challenges in quantifying individual differences in cognition and provide concrete methodological recommendations. In particular, future studies would benefit from using multiple task variants to ensure they target specific, clearly defined cognitive traits and from conducting repeated testing to assess individual consistency. We then consider how neural, genetic, developmental and behavioural factors may generate individual differences in cognition. Finally, we discuss the potential fitness consequences of individual cognitive variation and place these into an evolutionary framework with testable hypotheses. We intend for this special issue to stimulate researchers to position individual variation at the centre of the cognitive sciences.This article is part of the theme issue 'Causes and consequences of individual differences in cognitive abilities'.

Rhesus macaques use probabilities to predict future events

Humans can use an intuitive sense of statistics to make predictions about uncertain future events, a cognitive skill that underpins logical and mathematical reasoning. Recent research shows that some of these abilities for statistical inferences can emerge in preverbal infants and non-human primates such as apes and capuchins. An important question is therefore whether animals share the full complement of intuitive reasoning abilities demonstrated by humans, as well as what evolutionary contexts promote the emergence of such skills. Here, we examined whether free-ranging rhesus macaques (Macaca mulatta) can use probability information to infer the most likely outcome of a random lottery, in the first test of whether primates can make such inferences in the absence of direct prior experience. We developed a novel expectancy-violation looking time task, adapted from prior studies of infants, in order to assess the monkeys' expectations. In Study 1, we confirmed that monkeys (n = 20) looked similarly at different sampled items if they had no prior knowledge about the population they were drawn from. In Study 2, monkeys (n = 80) saw a dynamic 'lottery' machine containing a mix of two types of fruit outcomes, and then saw either the more common fruit (expected trial) or the relatively rare fruit (unexpected trial) fall from the machine. We found that monkeys looked longer when they witnessed the unexpected outcome. In Study 3, we confirmed that this effect depended on the causal relationship between the sample and the population, not visual mismatch: monkeys (n = 80) looked equally at both outcomes if the experimenter pulled the sampled item from her pocket. These results reveal that rhesus monkeys spontaneously use information about probability to reason about likely outcomes, and show how comparative studies of nonhumans can disentangle the evolutionary history of logical reasoning capacities.

Wild jackdaws are wary of objects that violate expectations of animacy

Nature is composed of self-propelled, animate agents and inanimate objects. Laboratory studies have shown that human infants and a few species discriminate between animate and inanimate objects. This ability is assumed to have evolved to support social cognition and filial imprinting, but its ecological role for wild animals has never been examined. An alternative, functional explanation is that discriminating stimuli based on their potential for animacy helps animals distinguish between harmless and threatening stimuli. Using remote-controlled experimental stimulus presentations, we tested if wild jackdaws (Corvus monedula) respond fearfully to stimuli that violate expectations for movement. Breeding pairs (N = 27) were presented at their nests with moving and non-moving models of ecologically relevant stimuli (birds, snakes and sticks) that differed in threat level and propensity for independent motion. Jackdaws were startled by movement regardless of stimulus type and produced more alarm calls when faced with animate objects. However, they delayed longest in entering their nest-box after encountering a stimulus that should not move independently, suggesting they recognized the movement as unexpected. How jackdaws develop expectations about object movement is not clear, but our results suggest that discriminating between animate and inanimate stimuli may trigger information gathering about potential threats.

Meta-analytic techniques reveal that corvid causal reasoning in the Aesop's Fable paradigm is driven by trial-and-error learning

The classic Aesop's fable, Crow and the Pitcher, has inspired a major line of research in comparative cognition. Over the past several years, five articles (over 32 experiments) have examined the ability of corvids (e.g., rooks, crows, and jays) to complete lab-based analogs of this fable, by requiring them to drop stones and other objects into tubes of water to retrieve a floating worm (Bird and Emery in Curr Biol 19:1-5, 2009b; Cheke et al. in Anim Cogn 14:441-455, 2011; Jelbert et al. in PLoS One 3:e92895, 2014; Logan et al. in PLoS One 7:e103049, 2014; Taylor et al. in Gray R D 12:e26887, 2011). These researchers have stressed the unique potential of this paradigm for understanding causal reasoning in corvids. Ghirlanda and Lind (Anim Behav 123:239-247, 2017) re-evaluated trial-level data from these studies and concluded that initial preferences for functional objects, combined with trial-and-error learning, may account for subjects' performance on key variants of the paradigm. In the present paper, we use meta-analytic techniques to provide more precise information about the rate and mode of learning that occurs within and across tasks. Within tasks, subjects learned from successful (but not unsuccessful) actions, indicating that higher-order reasoning about phenomena such as mass, volume, and displacement is unlikely to be involved. Furthermore, subjects did not transfer information learned in one task to subsequent tasks, suggesting that corvids do not engage with these tasks as variants of the same problem (i.e., how to generate water displacement to retrieve a floating worm). Our methodological analysis and empirical findings raise the question: Can Aesop's fable studies distinguish between trial-and-error learning and/or higher-order causal reasoning? We conclude they cannot.

Constructive anthropomorphism: a functional evolutionary approach to the study of human-like cognitive mechanisms in animals

Anthropomorphism, the attribution of human cognitive processes and emotional states to animals, is commonly viewed as non-scientific and potentially misleading. This is mainly because apparent similarity to humans can usually be explained by alternative, simpler mechanisms in animals, and because there is no explanatory power in analogies to human phenomena when these phenomena are not well understood. Yet, because it is also difficult to preclude real similarity and continuity in the evolution of humans' and animals' cognitive abilities, it may not be productive to completely ignore our understanding of human behaviour when thinking about animals. Here we propose that in applying a functional approach to the evolution of cognitive mechanisms, human cognition may be used to broaden our theoretical thinking and to generate testable hypotheses. Our goal is not to 'elevate' animals, but rather to find the minimal set of mechanistic principles that may explain 'advanced' cognitive abilities in humans, and consider under what conditions these mechanisms were likely to enhance fitness and to evolve in animals. We illustrate this approach, from relatively simple emotional states, to more advanced mechanisms, involved in planning and decision-making, episodic memory, metacognition, theory of mind, and consciousness.

The performance of cleaner wrasse, Labroides dimidiatus, in a reversal learning task varies across experimental paradigms

Testing performance in controlled laboratory experiments is a powerful tool for understanding the extent and evolution of cognitive abilities in non-human animals. However, cognitive testing is prone to a number of potential biases, which, if unnoticed or unaccounted for, may affect the conclusions drawn. We examined whether slight modifications to the experimental procedure and apparatus used in a spatial task and reversal learning task affected performance outcomes in the bluestreak cleaner wrasse, Labroides dimidiatus (hereafter “cleaners”). Using two-alternative forced-choice tests, fish had to learn to associate a food reward with a side (left or right) in their holding aquarium. Individuals were tested in one of four experimental treatments that differed slightly in procedure and/or physical set-up. Cleaners from all four treatment groups were equally able to solve the initial spatial task. However, groups differed in their ability to solve the reversal learning task: no individuals solved the reversal task when tested in small tanks with a transparent partition separating the two options, whereas over 50% of individuals solved the task when performed in a larger tank, or with an opaque partition. These results clearly show that seemingly insignificant details to the experimental set-up matter when testing performance in a spatial task and might significantly influence the outcome of experiments. These results echo previous calls for researchers to exercise caution when designing methodologies for cognition tasks to avoid misinterpretations.

How comparative psychology can shed light on human evolution: Response to Beran et al.'s discussion of "Cognitive capacities for cooking in chimpanzees"

We recently reported a study (Warneken & Rosati Proceedings of the Royal Society B, 282, 20150229, 2015) examining whether chimpanzees possess several cognitive capacities that are critical to engage in cooking. In a subsequent commentary, Beran, Hopper, de Waal, Sayers, and Brosnan Learning & Behavior (2015) asserted that our paper has several flaws. Their commentary (1) critiques some aspects of our methodology and argues that our work does not constitute evidence that chimpanzees can actually cook; (2) claims that these results are old news, as previous work had already demonstrated that chimpanzees possess most or all of these capacities; and, finally, (3) argues that comparative psychological studies of chimpanzees cannot adequately address questions about human evolution, anyway. However, their critique of the premise of our study simply reiterates several points we made in the original paper. To quote ourselves: "As chimpanzees neither control fire nor cook food in their natural behavior, these experiments therefore focus not on whether chimpanzees can actually cook food, but rather whether they can apply their cognitive skills to novel problems that emulate cooking" (Warneken & Rosati Proceedings of the Royal Society B, 282, 20150229, 2015, p. 2). Furthermore, the methodological issues they raise are standard points about psychological research with animals-many of which were addressed synthetically across our 9 experiments, or else are orthogonal to our claims. Finally, we argue that comparative studies of extant apes (and other nonhuman species) are a powerful and indispensable method for understanding human cognitive evolution.

The Pertinence of Studying Neuroethology in Nonhuman Primates for Human Behavior in Groups and Organizations

Are we the only living beings endowed with a complex communicative system and sharp sociocognitive skills? How did these remarkable abilities develop? Even raised several centuries ago, those questions are still nourishing the current research and debates. A relevant approach for identifying the dynamics in the evolution of humans’ social and communicative abilities appears to study our closest living relatives, the nonhuman primates. In this article I focus on two abilities that drove the building of our unique sociality and are still playing a crucial role in daily human behaviors in groups and organizations: (a) the origins of human language, through the study of nonhuman primates gestures, vocalizations, and facial expressions and (b) the precursors and underpinning neural mechanisms of our ability to assess others’ mental states, that is, theory of mind. In each part, examples illustrate the advantages and limitations of the different methodological approaches used in research on nonhuman primates’ communication and social abilities and discuss the results in light of the current hypotheses and still open debates on what make the singularity of our species.

Individual differences in children's innovative problem-solving are not predicted by divergent thinking or executive functions

Recent studies of children's tool innovation have revealed that there is variation in children's success in middle-childhood. In two individual differences studies, we sought to identify personal characteristics that might predict success on an innovation task. In Study 1, we found that although measures of divergent thinking were related to each other they did not predict innovation success. In Study 2, we measured executive functioning including: inhibition, working memory, attentional flexibility and ill-structured problem-solving. None of these measures predicted innovation, but, innovation was predicted by children's performance on a receptive vocabulary scale that may function as a proxy for general intelligence. We did not find evidence that children's innovation was predicted by specific personal characteristics.

Do monkeys have a theory of mind? How to answer the question?

Since Premack and Woodruf (1978), the study of mindreading abilities in nonhumans, especially primates, has been thoroughly investigated. But attempts to understand the evolution of this aspect of human intelligence have mainly focused on comparisons between apes and human infants, while relatively little is known about the abilities of monkeys. This lack of data on monkeys seems mainly due to the hypothesis of a cognitive "gap" between apes and monkeys. However, in recent years monkeys have been featuring more prominently in the landscape of social cognition research, and some of these systematic studies appear promising. This paper reviews i) current knowledge about monkeys' socio-cognitive abilities, especially regarding gaze processing, attention and intention reading, and perspective-taking, ii) alternative hypotheses regarding the underlying mechanisms of such complex behaviors, and iii) potential new perspectives and future directions for studying ToM in monkeys.

The evolution of general intelligence

The presence of general intelligence poses a major evolutionary puzzle, which has led to increased interest in its presence in nonhuman animals. The aim of this review is to critically evaluate this question and to explore the implications for current theories about the evolution of cognition. We first review domain-general and domain-specific accounts of human cognition in order to situate attempts to identify general intelligence in nonhuman animals. Recent studies are consistent with the presence of general intelligence in mammals (rodents and primates). However, the interpretation of a psychometric g factor as general intelligence needs to be validated, in particular in primates, and we propose a range of such tests. We then evaluate the implications of general intelligence in nonhuman animals for current theories about its evolution and find support for the cultural intelligence approach, which stresses the critical importance of social inputs during the ontogenetic construction of survival-relevant skills. The presence of general intelligence in nonhumans implies that modular abilities can arise in two ways, primarily through automatic development with fixed content and secondarily through learning and automatization with more variable content. The currently best-supported model, for humans and nonhuman vertebrates alike, thus construes the mind as a mix of skills based on primary and secondary modules. The relative importance of these two components is expected to vary widely among species, and we formulate tests to quantify their strength.

Brief Report: Chimpanzee Social Responsiveness Scale (CSRS) Detects Individual Variation in Social Responsiveness for Captive Chimpanzees

Comparative studies of social responsiveness, a core impairment in autism spectrum disorder (ASD), will enhance our understanding of typical and atypical social behavior. We previously reported a quantitative, cross-species (human-chimpanzee) social responsiveness measure, which included the development of the Chimpanzee Social Responsiveness Scale (CSRS). Here, we augment our prior CSRS sample with 25 zoo chimpanzees at three sites: combined N = 54. The CSRS demonstrated strong interrater reliability, and low-ranked chimpanzees, on average, displayed higher CSRS scores. The CSRS continues to discriminate variation in chimpanzee social responsiveness, and the association of higher scores with lower chimpanzee social standing has implications for the relationship between autistic traits and human social status. Continued comparative investigations of social responsiveness will enhance our understanding of underlying impairments in ASD, improve early diagnosis, and inform future therapies.

Human-chimpanzee differences in a FZD8 enhancer alter cell-cycle dynamics in the developing neocortex

The human neocortex differs from that of other great apes in several notable regards, including altered cell cycle, prolonged corticogenesis, and increased size [1-5]. Although these evolutionary changes most likely contributed to the origin of distinctively human cognitive faculties, their genetic basis remains almost entirely unknown. Highly conserved non-coding regions showing rapid sequence changes along the human lineage are candidate loci for the development and evolution of uniquely human traits. Several studies have identified human-accelerated enhancers [6-14], but none have linked an expression difference to a specific organismal trait. Here we report the discovery of a human-accelerated regulatory enhancer (HARE5) of FZD8, a receptor of the Wnt pathway implicated in brain development and size [15, 16]. Using transgenic mice, we demonstrate dramatic differences in human and chimpanzee HARE5 activity, with human HARE5 driving early and robust expression at the onset of corticogenesis. Similar to HARE5 activity, FZD8 is expressed in neural progenitors of the developing neocortex [17-19]. Chromosome conformation capture assays reveal that HARE5 physically and specifically contacts the core Fzd8 promoter in the mouse embryonic neocortex. To assess the phenotypic consequences of HARE5 activity, we generated transgenic mice in which Fzd8 expression is under control of orthologous enhancers (Pt-HARE5::Fzd8 and Hs-HARE5::Fzd8). In comparison to Pt-HARE5::Fzd8, Hs-HARE5::Fzd8 mice showed marked acceleration of neural progenitor cell cycle and increased brain size. Changes in HARE5 function unique to humans thus alter the cell-cycle dynamics of a critical population of stem cells during corticogenesis and may underlie some distinctive anatomical features of the human brain.

High bandwidth synaptic communication and frequency tracking in human neocortex

Neuronal firing, synaptic transmission, and its plasticity form the building blocks for processing and storage of information in the brain. It is unknown whether adult human synapses are more efficient in transferring information between neurons than rodent synapses. To test this, we recorded from connected pairs of pyramidal neurons in acute brain slices of adult human and mouse temporal cortex and probed the dynamical properties of use-dependent plasticity. We found that human synaptic connections were purely depressing and that they recovered three to four times more swiftly from depression than synapses in rodent neocortex. Thereby, during realistic spike trains, the temporal resolution of synaptic information exchange in human synapses substantially surpasses that in mice. Using information theory, we calculate that information transfer between human pyramidal neurons exceeds that of mouse pyramidal neurons by four to nine times, well into the beta and gamma frequency range. In addition, we found that human principal cells tracked fine temporal features, conveyed in received synaptic inputs, at a wider bandwidth than for rodents. Action potential firing probability was reliably phase-locked to input transients up to 1,000 cycles/s because of a steep onset of action potentials in human pyramidal neurons during spike trains, unlike in rodent neurons. Our data show that, in contrast to the widely held views of limited information transfer in rodent depressing synapses, fast recovering synapses of human neurons can actually transfer substantial amounts of information during spike trains. In addition, human pyramidal neurons are equipped to encode high synaptic information content. Thus, adult human cortical microcircuits relay information at a wider bandwidth than rodent microcircuits.

Decoding the molecular evolution of human cognition using comparative genomics

Identification of genetic and molecular factors responsible for the specialized cognitive abilities of humans is expected to provide important insights into the mechanisms responsible for disorders of cognition such as autism, schizophrenia and Alzheimer's disease. Here, we discuss the use of comparative genomics for identifying salient genes and gene networks that may underlie cognition. We focus on the comparison of human and non-human primate brain gene expression and the utility of building gene coexpression networks for prioritizing hundreds of genes that differ in expression among the species queried. We also discuss the importance of and methods for functional studies of the individual genes identified. Together, this integration of comparative genomics with cellular and animal models should provide improved systems for developing effective therapeutics for disorders of cognition.

Does metarepresentation make human mental time travel unique?

Recent neurological evidence suggests that rats can mentally represent novel spatial trajectories and then are more likely to follow these paths in the future. Consequently, it has been proposed that human and nonhuman mental time travel capacities may differ in degree rather than kind. As of yet, however, there is no evidence for the crucial and qualitatively distinct component of metarepresentation in any nonhuman animal, not even our closest great ape relatives. Metarepresentation allows humans to represent the relationship between current reality and mere representations of reality-including those of the future. Drawing on parallels with dreaming and mind-wandering, I outline the future-oriented benefits associated with uncontextualized (non-metarepresentational) representations of past and novel events, but propose that further, immense benefits flowed from the addition of metarepresentational insight. I critique previous behavioral paradigms used to assess mental time travel in animals and suggest how future-oriented metarepresentation might possibly be demonstrated nonverbally. WIREs Cogn Sci 2014, 5:519-531. doi: 10.1002/wcs.1308 For further resources related to this article, please visit the WIREs website.

CONFLICT OF INTEREST

The author has declared no conflicts of interest for this article.

The evolution of self-control

Cognition presents evolutionary research with one of its greatest challenges. Cognitive evolution has been explained at the proximate level by shifts in absolute and relative brain volume and at the ultimate level by differences in social and dietary complexity. However, no study has integrated the experimental and phylogenetic approach at the scale required to rigorously test these explanations. Instead, previous research has largely relied on various measures of brain size as proxies for cognitive abilities. We experimentally evaluated these major evolutionary explanations by quantitatively comparing the cognitive performance of 567 individuals representing 36 species on two problem-solving tasks measuring self-control. Phylogenetic analysis revealed that absolute brain volume best predicted performance across species and accounted for considerably more variance than brain volume controlling for body mass. This result corroborates recent advances in evolutionary neurobiology and illustrates the cognitive consequences of cortical reorganization through increases in brain volume. Within primates, dietary breadth but not social group size was a strong predictor of species differences in self-control. Our results implicate robust evolutionary relationships between dietary breadth, absolute brain volume, and self-control. These findings provide a significant first step toward quantifying the primate cognitive phenome and explaining the process of cognitive evolution.

Simple minds: a qualified defence of associative learning

Using cooperation in chimpanzees as a case study, this article argues that research on animal minds needs to steer a course between 'association-blindness'--the failure to consider associative learning as a candidate explanation for complex behaviour--and 'simple-mindedness'--the assumption that associative explanations trump more cognitive hypotheses. Association-blindness is challenged by the evidence that associative learning occurs in a wide range of taxa and functional contexts, and is a major force guiding the development of complex human behaviour. Furthermore, contrary to a common view, association-blindness is not entailed by the rejection of behaviourism. Simple-mindedness is founded on Morgan's canon, a methodological principle recommending 'lower' over 'higher' explanations for animal behaviour. Studies in the history and philosophy of science show that Morgan failed to offer an adequate justification for his canon, and subsequent attempts to justify the canon using evolutionary arguments and appeals to simplicity have not been successful. The weaknesses of association-blindness and simple-mindedness imply that there are no short-cuts to finding out about animal minds. To decide between associative and yet more cognitive explanations for animal behaviour, we have to spell them out in sufficient detail to allow differential predictions, and to test these predictions through observation and experiment.

Linking behavioural syndromes and cognition: a behavioural ecology perspective

With the exception of a few model species, individual differences in cognition remain relatively unstudied in non-human animals. One intriguing possibility is that variation in cognition is functionally related to variation in personality. Here, we review some examples and present hypotheses on relationships between personality (or behavioural syndromes) and individual differences in cognitive style. Our hypotheses are based largely on a connection between fast-slow behavioural types (BTs; e.g. boldness, aggressiveness, exploration tendency) and cognitive speed-accuracy trade-offs. We also discuss connections between BTs, cognition and ecologically important aspects of decision-making, including sampling, impulsivity, risk sensitivity and choosiness. Finally, we introduce the notion of cognition syndromes, and apply ideas from theories on adaptive behavioural syndromes to generate predictions on cognition syndromes.