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The ability to think about and plan for the future is a critical cognitive skill for our daily life. There is ongoing debate about whether other animals possess future thinking. Part of the difficulty in resolving this debate is that there is not a definite methodology that allow us to conclude that animals (and human children) are truly thinking about a future event. Research with humans—both children and adults- will benefit the field of comparative psychology by providing information about the range of humans' responses when they are faced with problems similar to those presented to other animals. Inspired by a problem that chimpanzees experienced in the wild, children of 4 and 5 years of age and young adults were presented with a situation in which they were expected to select two tools in order to obtain a reward. More older children than 4 years old successfully obtained the reward. Adults also succeeded at solving the problem. However, both children and adults struggled to select the two correct tools before any tool-use action was executed. While children's performance is discussed in the context of temporal components required to envisage future events, adults' performance is interpreted in the context of cognitive effort. These findings link developmental and adult cognition with comparative psychology. [ABSTRACT FROM AUTHOR]

People have a good intuition of how to move a computer mouse to place a cursor at a desired position on a screen. This is surprising because the hand and the mouse are at different locations and they generally move in different directions and over different distances. But using a computer mouse is not always intuitive: try positioning a cursor after turning the mouse by 90° in your hand. To examine when using a computer mouse is intuitive, we asked participants to move a cursor to targets on a screen by moving a mouse along a surface. We varied the orientation of this surface in space and that of the mouse in the hand. Participants performed best when the mapping between hand and cursor motion was close to what we are accustomed to, either in space or relative to the forearm. [ABSTRACT FROM AUTHOR]

Nut-cracking is often cited as one of the most complex behaviours observed in wild chimpanzees. However, the cognitive mechanisms behind its acquisition are still debated. The current null hypothesis is that the form of nut-cracking behaviour relies on variants of social learning, with some researchers arguing, more precisely, that copying variants of social learning mechanisms are necessary. However, to date, very few experiments have directly investigated the potentially sufficient role of individual learning in explaining the behavioural form of nut-cracking. Despite this, the available data provides some evidence for the spontaneous acquisition of nut-cracking by chimpanzees; later group acquisition was then found to be at least facilitated by (unspecified) variants of social learning. The latter findings are in line with both suggested hypotheses, i.e., that copying social learning is required and that other (noncopying) social learning mechanisms are at play. Here we present the first study which focused (initially) on the role of individual learning for the acquisition of the nutcracking behavioural form in chimpanzees.Wetested task-naïve chimpanzees (N = 13) with an extended baseline condition to examine whether the behaviour would emerge spontaneously. After the baseline condition (which was unsuccessful), we tested for the role of social learning by providing social information in a step-wise fashion, culminating in a full action demonstration of nut-cracking by a human demonstrator (this last condition made it possible for the observers to copy all actions underlying the behaviour). Despite the opportunities to individually and/or socially learn nutcracking, none of the chimpanzees tested here cracked nuts using tools in any of the conditions in our study; thus, providing no conclusive evidence for either competing hypothesis. We conclude that this failure was the product of an interplay of factors, including behavioural conservatism and the existence of a potential sensitive learning period for nut-cracking in chimpanzees. The possibility remains that nut-cracking is a behaviour that chimpanzees can individually learn. However, this behaviour might only be acquired when chimpanzees are still inside their sensitive learning period, and when ecological and developmental conditions allow for it. The possibility remains that nut-cracking is an example of a culture dependent trait in non-human great apes. Recommendations for future research projects to address this question are considered. [ABSTRACT FROM AUTHOR]

Adjustment of percussive movements to match the energetic requirements of the task serves as an index of skill in stone-knapping and nut-cracking. In this study, we compared strike-by-strike adjustment of percussive movements in expert bearded capuchin monkeys (Sapajus libidinosus) and (novice and expert) humans cracking palm nuts (Astrocaryum spp.) using stone hammers of varying mass. The monkeys regulated each strike's amplitude and hammer's velocity at impact to a small degree based on the propagation of a fracture in the nut's shell but overall struck a nut with consistent kinetic energy for a given hammer. They showed the smallest movement variability across strikes among all groups. Novice humans took the most strikes to crack a nut among all groups. Expert humans took the fewest strikes among all groups while showing the largest variation in hammer's kinetic energy at impact and largest movement variability across strikes. Overall, our findings confirm that expert humans can adjust their strikes more precisely to meet variable task demands and are more efficient than monkeys or novice humans in cracking nuts, but the findings also show a surprising advantage for expert monkeys over novice humans. The monkeys' strategy of striking with consistent amplitude and velocity is advantageous when hammer mass is adequate to generate sufficient kinetic energy at impact and crack open a nut in few strikes without requiring fine adjustments, explaining why the monkeys are particularly attentive to a stone's mass when choosing it as a hammer. [ABSTRACT FROM AUTHOR]

Cumulative culture is a transformative force in human evolution, but the social underpinnings of this capacity are debated. Identifying social influences on how chimpanzees acquire tool tasks of differing complexity may help illuminate the evolutionary origins of technology in our own lineage. Humans routinely transfer tools to novices to scaffold their skill development. While tool transfers occur in wild chimpanzees and fulfill criteria for teaching, it is unknown whether this form of helping varies between populations and across tasks. Applying standardized methods, we compared tool transfers during termite gathering by chimpanzees in the Goualougo Triangle, Republic of Congo, and in Gombe, Tanzania. At Goualougo, chimpanzees use multiple, different tool types sequentially, choose specific raw materials, and perform modifications that improve tool efficiency, which could make it challenging for novices to manufacture suitable tools. Termite gathering at Gombe involves a single tool type, fishing probes, which can be manufactured from various materials. Multiple measures indicated population differences in tool-transfer behavior. The rate of transfers and probability of transfer upon request were significantly higher at Goualougo, while resistance to transfers was significantly higher at Gombe. Active transfers of tools in which possessors moved to facilitate possession change upon request occurred only at Goualougo, where they were the most common transfer type. At Gombe, tool requests were typically refused. We suggest that these population differences in tool-transfer behavior may relate to task complexity and that active helping plays an enhanced role in the cultural transmission of complex technology in wild apes. [ABSTRACT FROM AUTHOR]

Producing a tool use gesture is a complex process drawing upon the integration of stored knowledge of tools and their associated actions with sensory-motor mechanisms supporting the planning and control of hand and arm actions. Understanding how sensory-motor systems in parietal cortex interface with semantic representations of actions and objects in the temporal lobe remains a critical issue and is hypothesized to be a key determinant of the severity of limb apraxia, a deficit in producing skilled action after left hemisphere stroke. We used voxel-based and connectome-based lesion-symptom mapping with data from 57 left hemisphere stroke participants to assess the lesion sites and structural disconnection patterns associated with poor tool use gesturing. We found that structural disconnection among the left inferior parietal lobule, lateral and ventral temporal cortices, and middle and superior frontal gyri predicted the severity of tool use gesturing performance. Control analyses demonstrated that reductions in right-hand grip strength were associated with motor system disconnection, largely bypassing regions supporting tool use gesturing. Our findings provide evidence that limb apraxia may arise, in part, from a disconnection between conceptual representations in the temporal lobe and mechanisms enabling skilled action production in the inferior parietal lobule. [ABSTRACT FROM AUTHOR]

Previous studies have shown that tool use affects the plasticity of the body schema. In other words, people will perceive the tool as a part of their body, and thus feel like they have "longer limbs" after using tools. However, it is unclear whether tool embodiment could spread to a limb that is not using the tool, and whether other limbs could utilize the proprioception of a limb. In Experiment 1, blindfolded participants were asked to search with a cane (Condition 1) or to walk with a cane (Condition 2). The results in Condition 1 illustrated that the tactile distance perception on the forearm was lengthened after tool use, while other body parts did not significantly change. In Condition 2, the tactile distance perception on the hand and forearm extended significantly after using tools. Additionally, tool-use training even induced an increased perception of the calf that was not using the tool. Possible interference from the difference between walking and standing was excluded in Experiment 2. These results demonstrate that the proprioception information of one limb could be exploited by another limb to extend the body schema even though that limb was not using a tool. It was also observed that the effect of direction was task-dependent in the tactile perception task. [ABSTRACT FROM AUTHOR]

In this theoretical review article, our primary goal is to contribute to the post-cognitivist understanding of learning to perceive and perceiving as learning, by discussing a framework for perception and perceptual learning initiated by James J Gibson, and extended by Eleanor J Gibson and others. This Ecological Psychology has a coherent set of assumptions based on the concept of mutualism between the perceiving organism and its surroundings, and the idea of affordances as action possibilities of the surround that are perceptible by the organism. At the same time, Ecological Psychology, broadly construed, consists of different perspectives that take different routes to address questions related to the core concepts of perceptual learning. In this article, we focus on three theoretical stances within Ecological Psychology on the issue of perceptual learning: that of Eleanor J Gibson, the current theory of direct learning by Jacobs and Michaels, and the "organicist" approach based on ideas of organicist biology and developments in evolutionary biology. We consider perceptual learning as embedded in development and evolution, and we explore perceptual learning in more depth in the context of tool use and language development. We also discuss the relation between Ecological Psychology and Enactivism on the nature of perception. In conclusion, we summarize the benefits of Ecological Psychology, as a robust but still developing post-cognitivist framework, for the study of perceptual learning and cognitive science in general. [ABSTRACT FROM AUTHOR]

Since the discovery of mirror neurons in the 1990s, many neuroimaging studies have tackled the issue of action observation with the aim of unravelling a putative homolog human system. However, these studies do not distinguish between non-tool-use versus tool-use actions, implying that a common brain network is systematically involved in the observation of any action. Here we provide evidence for a brain network dedicated to tool-use action observation, called the tool-use observation network, mostly situated in the left hemisphere, and distinct from the non-tool-use action observation network. Areas specific for tool-use action observation are the left cytoarchitectonic area PF within the left inferior parietal lobe and the left inferior frontal gyrus. The neural correlates associated with the observation of tool-use reported here offer new insights into the neurocognitive bases of action observation and tool use, as well as addressing more fundamental issues on the origins of specifically human phenomena such as cumulative technological evolution. [ABSTRACT FROM AUTHOR]

The aim of this study is to establish the effects of stick use on rhythmic bimanual coordination in drummers. Eighteen drummers performed a rapid antiphase coordination task using their fingers and handheld drumsticks. We found no significant differences in the speed of tapping between finger and stick-use tapping, while stick-use tapping had a larger peak force and smaller variability in coordination pattern than finger tapping. As a consequence, the quotient of the number of taps divided by the variability of coordination pattern, named the bimanual performance quotient, was higher for stick-use tapping than for finger tapping. A significant correlation was found between years of drumming experience and the bimanual performance quotient for both finger and stick-use tapping, but not between the years of drumming experience and the degree of improvement in the bimanual performance quotient with stick use relative to finger tapping. These results indicate that stick use enhances drummers' bimanual coordination during rapid alternate tapping, whereas the degree of improvement with stick use does not depend on drumming experience. [ABSTRACT FROM AUTHOR]

Artificial termite-fishing tasks are a common enrichment for captive great apes, promoting species-typical behaviors. Nonetheless, whether these activities are linked to changes in other behaviors and whether these changes persist over time has seldom been investigated. We assessed whether the use of an artificial termite-fishing task was linked to changes in the solitary behavior and social dynamics in two groups of sanctuary-housed chimpanzees (Pan troglodytes). Specifically, we compared chimpanzee behavior during eight enrichment sessions distributed over a two-month period, with similar periods before and after the introduction of the enrichment. Data were collected from combined interval and continuous sampling methods and were analyzed using generalized linear mixed models. We found that participation increased across sessions and that both enrichment and participation predicted an increase in tool use and feeding and a decrease in inactivity, which were all maintained throughout the sessions. Furthermore, participation was positively associated with social proximity, revealing a gathering effect of the task. However, neither enrichment nor participation were linked to changes in abnormal, self-directed, affiliation-related or aggression-related behaviors. Overall, our results support the hypothesis that artificial termite-fishing is a suitable enrichment for captive chimpanzees, maintaining the subjects’ interest and promoting species-typical behaviors, with no negative effects on social activities.

In order to deepen the understanding of the intrinsic interactions and interplay between humans, tools, and environment from a systems perspective, research in the wild (RITW) approaches have gained traction during recent decades as they provide a higher ecological validity of findings. This paper presents a RITW study, investigating how assembly, in this case dock assembly of forwarders, was done in practice. As our theoretical foundation, we used the framework of distributed cognition, which is one of the main pillars of RITW. The findings are presented in narrative form, describing and highlighting that the workers achieve an efficient production outcome by being integral parts of the whole production process and doing so through coordination of activities benefitting the shared goal of the distributed socio-technical system.

Keywords: tool use; dog cognition; cognitive evolution; comparative cognition; methods of behavioral research EN tool use dog cognition cognitive evolution comparative cognition methods of behavioral research 1 3 3 07/24/21 20210722 NES 210722 Brooks and Yamamoto ([3]) attempt to shed new light on old facts, when they propose that dogs' notorious chewing of sticks could be an overlooked instance of tool use. Intentional behaviour in dog-human communication: an experimental analysis of "showing" behaviour in the dog. Therefore, to propose a widening of the definition in this manner, resembles a dog which tries to lift the extension of a mattress on which it is standing [but note, dogs do not do that (Lenkei et al., [14])]. [Extracted from the article]

The brain generally integrates a multitude of sensory signals to form a unified percept. Even in cursor control tasks, such as reaching while looking at rotated visual feedback on a monitor, visual information on cursor position and proprioceptive information on hand position are partially integrated (sensory coupling), resulting in mutual biases of the perceived positions of cursor and hand. Previous studies showed that the strength of sensory coupling (sum of the mutual biases) depends on the experience of kinematic correlations between hand movements and cursor motions, whereas the asymmetry of sensory coupling (difference between the biases) depends on the relative reliabilities (inverse of variability) of hand-position and cursor-position estimates (reliability rule). Furthermore, the precision of movement control and perception of hand position are known to differ between hands (left, right) and workspaces (ipsilateral, contralateral), and so does the experience of kinematic correlations from daily life activities. Thus, in the present study, we tested whether strength and asymmetry of sensory coupling for the endpoints of reaches in a cursor control task differ between the right and left hand and between ipsilateral and contralateral hemispace. No differences were found in the strength of sensory coupling between hands or between hemispaces. However, asymmetry of sensory coupling was less in ipsilateral than in contralateral hemispace: in ipsilateral hemispace, the bias of the perceived hand position was reduced, which was accompanied by a smaller variability of the estimates. The variability of position estimates of the dominant right hand was also less than for the non-dominant left hand, but this difference was not accompanied by a difference in the asymmetry of sensory coupling – a violation of the reliability rule, probably due a stronger influence of visual information on right-hand movements. According to these results, the long-term effects of the experienced kinematic correlation between hand movements and cursor motions on the strength of sensory coupling are generic and not specific for hemispaces or hands, whereas the effects of relative reliabilities on the asymmetry of sensory coupling are specific for hemispaces but not for hands.

It has been hypothesized that the evolution of tool use may have served as a preadaptation for the emergence of left hemispheric specialization in motor skill in humans. Here, we tested for intermanual differences in performance on a tool use task in a sample of 206 captive chimpanzees in relation to their sex, age, and hand preference. In addition, we examined heritability in tool use skill for the entire sample, as well as within 2 genetically isolated populations of captive chimpanzees. This was done to determine the degree of reproducibility in heritability on motor performance. The results revealed a significant effect of hand preference on intermanual differences in performance. Right-handed chimpanzees performed the task more quickly with their right compared with left hand. In contrast, no significant intermanual differences in performance were found in left- and ambiguous-handed apes. Tool use performance was found to be significantly heritable for overall performance, as well as separately for the left and right hands. Further, significant heritability in tool use performance was found in both populations of apes, suggesting these results were reproducible. The results are discussed in the context of evolutionary theories of handedness and hemispheric specialization and the genetic mechanisms that underlie their expression in primates, including humans. [ABSTRACT FROM AUTHOR]

Capuchins (Sapajus apella) and squirrel monkeys (Saimiri sciureus) participated in 3 experiments in which they were presented with 2 objects, one appropriately oriented and the other inappropriately oriented to retrieve a food reward by pulling, replicating prior experiments with nonhuman primates described as evaluating "tool choice." Choice patterns were analyzed to assess whether monkeys learned that tools needed to be oriented with part of the tool on the far side of the reward to pull in the food. Both species learned to choose appropriately oriented tools after a similar number of sessions with a cane-shaped tool in the first task. Both species also transferred to a new tool shape in the second task, but squirrel monkeys' performance on particular trials suggested they did not use the functional relationship between the tool and the food to guide their choices. Tool shapes and configurations in the final task were designed to control for the potential use of extraneous spatial cues. Neither capuchins nor squirrel monkeys chose appropriately oriented tools above chance in control trials. Results suggest both species relied on other spatial cues to perform in previous tasks rather than learning to attend to the functional spatial relationship between a tool and a reward. Species differences emerged in the second task only, as capuchins mastered performance with the new tool shape faster than squirrel monkeys and seemed to use a more complex set of rules to guide their choices. [ABSTRACT FROM AUTHOR]

Here, we report an observation of a zoo‐housed common raven (Corvus corax) modifying and using a raven feather as a tool to access the food cache of her partner. We believe this record is of importance, as it represents one of the first cases of untrained common ravens spontaneously using and modifying a tool, and a rare example of a non‐human animal manufacturing a tool from a body part. This anecdotal observation suggests that tool use and tool modification may be present in the common raven behavioral repertoire in the foraging context; nevertheless, further investigations are needed to assess this possibility in more controlled settings as well as in the wild. [ABSTRACT FROM AUTHOR]

Nonhuman great apes show remarkable behavioural flexibility. Some individuals are even able to use water as a tool: They spit water into a vertical tube to make a peanut float upwards until it comes into reach (floating peanut task; FPT). In the current study, we used the FPT to investigate how visual feedback, an end-state demonstration and a social demonstration affect task performance in nonhuman great apes in three experiments. Our results indicate that apes who had acquired the solution with a clear tube maintained it with an opaque one. However, apes starting with an opaque tube failed to solve the task. Additionally, facing the peanut floating on a water-filled tube (i.e., an end-state demonstration) promoted success independent on the availability of visual feedback. Moreover, experiencing how water was poured into the tube either by a human demonstrator or by a water tap that had been opened either by the ape or a human did not seem to be of further assistance. First, this study suggests that great apes require visual feedback for solving the FPT, which is no longer required after the initial acquisition. Second, some subjects benefit from encountering the end-state, a finding corroborating previous studies. [ABSTRACT FROM AUTHOR]

Tool use has been reported in a wide range of vertebrates, but so far not in Suidae (the pigs). Suidae are widely considered to be "intelligent" and have many traits associated with tool use, so this is surprising. Here, we report the first structured observations of umprompted instrumental object manipulation in a pig, the Visayan warty pig Sus cebifrons , which we argue qualifies as tool use. Three individuals were observed using bark or sticks to dig with. Two individuals, adult females, used the sticks or bark, using a rowing motion, during the final stage of nest building. The third individual, an adult male, attempted to use a stick to dig with. Stick and branch manipulation was observed in other contexts, but not for digging. Our observations suggest the hypothesis that the observed use of stick to dig with could have been socially learned through vertical transmission (mother-daughter) as well as horizontal transmission (female-male). When used by the females, it altered their digging affordance, and had a specific placement in the nest-building sequence. In addition to its context-specificity and its role in a functional sequence, the observed tool use is distinguished by an ambiguous function or effectiveness as a digging behaviour, and the participation of the male in a female action pattern. Observations of unprompted tool use represented for the first time in a phylogenetic family are rare. These open new possibilities for research on tool use and social learning in Suidae. [ABSTRACT FROM AUTHOR]

We describe how the graphic tuskfish Choerodon graphicus in New Caledonia uses rocks and coral heads as anvils to break open bivalves to obtain food. Video revealed that C. graphicus can make as many as 28 strikes on two anvils over 6 min in a single event. This example of tool use in fishes extends the behaviour taxonomically and geographically and supports the hypothesis that tool use may be widespread in wrasses, particularly those in the Choerodon genus. [ABSTRACT FROM AUTHOR]

Prior research shows adults believe objects exist for specialised purposes. This "one tool, one function" cognitive bias promotes efficient mastery of artefact function but could mean individuals overlook an object's suitability for other functions. Across three studies, the initial trajectory of learning about functions was investigated to better depict when adults are constrained versus open in the assignment of functions to objects. Studies 1 and 2 employed an online format to deemphasise social expectations and explore how rapidly adults make exclusive tool-function pairings. Participants showed fixity immediately upon learning an object's function. Study 3 confirmed this with an in-person design. Furthermore, Study 3 evaluated descriptions adults gave to known and novel objects; for known items, adults focussed on functions and failed to note physical features. Adults appear deeply compelled to attach functions to objects, but in so doing, they may be less likely to perceive an object's potential for other uses. [ABSTRACT FROM AUTHOR]

The ability to solve novel problems is crucial for the survival and fitness of individuals living in dynamic environments. Studies of problem-solving date back to the beginning of the past century, but our knowledge is nonetheless still limited to very few taxa. In this study, we aimed to test a species of the order Carnivora, sloth bears (Melursus ursinus), on the ability to solve a novel foraging task. Bears were individually presented with honey spread on the wall and a familiar bucket, and, depending on the condition, they had to move the bucket and climb on it to access the honey. In follow-up conditions, they also repeatedly received cues to help them solve the task: before being tested, they either observed a human experimenter solving the problem or received direct relevant experience about how to solve the task. Despite high motivation, and in contrast to our predictions, none of the tested bears used the bucket to access out-of-reach food, even when social information and direct relevant experience were provided. These findings suggest that bears in this task may have failed to cognitively represent the problem and recognize the relevant aspects that would have led to its solution. [ABSTRACT FROM AUTHOR]

The neural representation of multisensory space near the body is modulated by the active use of long tools in non-human primates. Here, we investigated whether the electrophysiological correlates of visuo-tactile integration in near and far space were modulated by active tool use in healthy humans. Participants responded to a tactile target delivered to one hand while an irrelevant visual stimulus was presented ipsilaterally in near or far space. This crossmodal task was performed after the use of either short or long tools. Crucially, the P100 components elicited by visuo-tactile stimuli was enhanced on far as compared to near space trials after the use of long tools, while no such difference was present after short tool use. Thus, we found increased neural responses in brain areas encoding tactile stimuli to the body when visual stimuli were presented close to the tip of the tool after long tool use. This increased visuo-tactile integration on far space trials following the use of long tools might indicate a transient remapping of multisensory space. We speculate that performing voluntary actions with long tools strengthens the representation of sensory information arising within portions of space (i.e. the hand and the tip of the tool) that are most functionally relevant to one's behavioural goals. [ABSTRACT FROM AUTHOR]

Interacting with manipulable objects (tools) requires the integration of diverse computations supported by anatomically remote regions. Previous functional neuroimaging research has demonstrated the left supramarginal (SMG) exhibits functional connectivity to both ventral and dorsal pathways, supporting the integration of ventrally‐mediated tool properties and conceptual knowledge with dorsally‐computed volumetric and structural representations of tools. This architecture affords us the opportunity to test whether interactions between the left SMG, ventral visual pathway, and dorsal visual pathway are differentially modulated when participants plan and generate tool‐directed gestures emphasizing functional manipulation (tool use gesturing) or structure‐based grasping (tool transport gesturing). We found that functional connectivity between the left SMG, ventral temporal cortex (bilateral fusiform gyri), and dorsal visual pathway (left superior parietal lobule/posterior intraparietal sulcus) was maximal for tool transport planning and gesturing, whereas functional connectivity between the left SMG, left ventral anterior temporal lobe, and left frontal operculum was maximal for tool use planning and gesturing. These results demonstrate that functional connectivity to the left SMG is differentially modulated by tool use and tool transport gesturing, suggesting that distinct tool features computed by the two object processing pathways are integrated in the parietal lobe in the service of tool‐directed action. [ABSTRACT FROM AUTHOR]

Digging for underground storage organs of plants has been reported in various populations of wild chimpanzees (Pan troglodytes). However, it is unknown so far whether chimpanzees display lateral biases in manual digging as direct observations of this behavior are still lacking. It was therefore the aim of the present study to assess, for the first time, hand preferences for digging in a group of nine captive chimpanzees. We found that with only one exception, all individuals engaged in manual digging for buried food. Five individuals displayed a significant right-hand preference, two a significant left-hand preference, and one was ambidextrous. No apparent differences between males and females were found with regard to the direction or strength of hand preferences for manual digging. Only one out of four parent–offspring pairs was congruent in their preferred hand for manual digging. Three of the eight chimpanzees who dug manually also used tools in order to excavate buried food. Among those three individuals, one displayed a significant right-, one a significant left-hand preference, and one was ambidextrous. Only one of these three chimpanzees was consistent in preferring the same hand for manual and tool digging. The present findings are in line with the notion that chimpanzees display significant hand preferences at the individual level for haptic-guided behaviors, with a tendency for the right hand. [ABSTRACT FROM AUTHOR]

Power amplification allows animals to produce movements that exceed the physiological limits of muscle power and speed, such as the mantis shrimp's ultrafast predatory strike and the flea's jump. However, all known examples of nonhuman, muscle-driven power amplification involve anatomical structures that store energy from a single cycle of muscular contraction. Here,we describe a nonhuman example of external power amplification using a constructed device: the web of the triangle-weaver spider, Hyptiotes cavatus, which uses energy stored in the silk threads to actively tangle prey from afar. Hyptiotes stretches its web by tightening a separate anchor line over multiple cycles of limb motion, and then releases its hold on the anchor line when insects strike the web. Both spider and web spring forward 2 to 3 cm with a peak acceleration of up to 772.85 m/s2 so that up to four additional adhesive capture threads contact the prey while jerking caused by the spider's sudden stop subsequently wraps silk around the prey from all directions. Using webs as external "tools" to store energy offers substantial mechanical advantages over internal tissue-based power amplification due to the ability of Hyptiotes to load the web over multiple cycles of muscular contraction and thus release more stored energy during prey capture than would be possible with muscle-driven anatomical elastic-energy systems. Elastic power amplification is an underappreciated component of silk's function in webs and shows remarkable convergence to the fundamental mechanical advantages that led humans to engineer power-amplifying devices such as catapults and ballistae. [ABSTRACT FROM AUTHOR]

Homophilous behaviour plays a central role in the formation of human friendships. Individuals form social ties with others that show similar phenotypic traits, independently of relatedness. Evidence of such homophily can be found in bottlenose dolphins (Tursiops aduncus) in Shark Bay, Western Australia, where females that use marine sponges as foraging tools often associate with other females that use sponges. 'Sponging' is a socially learned, time-consuming behaviour, transmitted from mother to calf. Previous research illustrated a strong female bias in adopting this technique. The lower propensity for males to engage in sponging may be due to its incompatibility with adult male-specific behaviours, particularly the formation of multi-level alliances. However, the link between sponging and male behaviour has never been formally tested. Here, we show that male spongers associated significantly more often with other male spongers irrespective of their level of relatedness. Male spongers spent significantly more time foraging, and less time resting and travelling, than did male non-spongers. Interestingly, we found no difference in time spent socializing. Our study provides novel insights into the relationship between tool use and activity budgets of male dolphins, and indicates social homophily in the second-order alliance composition of tool-using bottlenose dolphins. [ABSTRACT FROM AUTHOR]

In the literature on apraxia of tool use, it is now accepted that using familiar tools requires semantic and mechanical knowledge. However, mechanical knowledge is nearly always assessed with production tasks, so one may assume that mechanical knowledge and familiar tool use are associated only because of their common motor mechanisms. This notion may be challenged by demonstrating that familiar tool use depends on an alternative tool selection task assessing mechanical knowledge, where alternative uses of tools are assumed according to their physical properties but where actual use of tools is not needed. We tested 21 left brain‐damaged patients and 21 matched controls with familiar tool use tasks (pantomime and single tool use), semantic tasks and an alternative tool selection task. The alternative tool selection task accounted for a large amount of variance in the single tool use task and was the best predictor among all the semantic tasks. Concerning the pantomime of tool use task, group and individual results suggested that the integrity of the semantic system and preserved mechanical knowledge are neither necessary nor sufficient to produce pantomimes. These results corroborate the idea that mechanical knowledge is essential when we use tools, even when tasks assessing mechanical knowledge do not require the production of any motor action. Our results also confirm the value of pantomime of tool use, which can be considered as a complex activity involving several cognitive abilities (e.g., communicative skills) rather than the activation of gesture engrams. [ABSTRACT FROM AUTHOR]

Although tool use disorders are frequent in neurodegenerative diseases, the question of which cognitive mechanisms are at stake is still under debate. Memory-based hypotheses (i.e., the semantic knowledge hypothesis and the manipulation knowledge hypothesis) posit that tool use relies solely on stored information about either tools or gestures whereas a reasoning-based hypothesis (i.e., the technical-semantic hypothesis) suggests that loss of semantic knowledge can be partially compensated by technical reasoning about the physical properties of tools and objects. These three hypotheses were tested by comparing performance of 30 healthy controls, 30 patients with Alzheimer's disease and 13 patients with semantic dementia in gesture production tasks (i.e., pantomime of tool use, single tool use, real tool use) and tool or gesture recognition tasks (i.e., functional and contextual matching, recognition of tool manipulation). Individual, item-based patterns of performance were analyzed to answer the following question: Could participants demonstrate the use of tools about which they had lost knowledge? With this aim in mind, "validation" and "rebuttal" frequencies were calculated based on each prediction. Predictions from the technical-semantic hypothesis were more frequently observed than memory-based predictions. A number of patients were able to use and demonstrate the use of tools for which they had lost either semantic or manipulation knowledge (or both). These data lead to question the role of different types of memory in tool use. The hypothesis of stored, tool-specific knowledge does not predict accurately clinical performances at the individual level. This may lead to explore the influence of either additional memory systems (e.g., personal/impersonal memory) or other modes of reasoning (e.g., theory of mind) on tool use skills. • The relative roles of memory and reasoning in tool use skills and disorders are still under debate. • This study tested the role of semantic/gestural memory and reasoning in gesture production and gesture recognition tasks. • Gesture recognition deficits did not prevent normal gesture production, which is at odds with memory-based hypotheses. [ABSTRACT FROM AUTHOR]

Studies investigating tool use in animals that are not known tool users in the wild are important in helping to understand how and under what circumstances this ability might arise. Tool use appears to be uncommon in great tits (Parus major), with only a single documented observation in which a wild great tit used conifer needles to extract larvae from crevices in trees. In a laboratory‐based experiment, we examined whether wild‐caught great tits could learn to use tools in a similar manner. We presented the birds with two different tool use tasks in which they would need to use either a stick or a hook to extract an otherwise inaccessible meal worm from a transparent plastic tube. First, the birds passed a simpler training criterion (pulling a tool with an attached food reward) that aimed to reduce the difficulty of the task. Nevertheless, none of the individuals learnt to use tools in either of the two tasks. This result stands in stark contrast to the abilities of some corvids and parrots, which can learn to use tools in captivity, even though some of them are not tool users in the wild. We believe that tool use might be difficult for some birds to learn since the skills required for this ability seem not to be part of their natural foraging behaviour. [ABSTRACT FROM AUTHOR]

Affordances are available behaviours emerging from relations between properties of animals and their environment. In any situation, multiple behaviours are available, that is, multiple affordances exist. We asked whether participants could detect means–ends relations among affordances (i.e., higher order affordances) in the context of reaching to a maximum height. We both assessed perceived affordances and evaluated actual reaching ability. In Experiment 1, we co-varied higher order goals (reaching to touch vs reaching to grasp) and the lower order effectors used to achieve the goals (fingertips vs a hand-held tool). In Experiment 2, we varied the lower order posture from which reaching would occur (standing vs kneeling). In both experiments, perceived maximum reaching height reflected relations between lower order means (effectors and postures) and higher order ends (reaching goals), and judgments closely reflected actual performance. We conclude that participants demonstrated prospective sensitivity to higher order affordances for reaching extended across multiple levels of the means–ends hierarchy. [ABSTRACT FROM AUTHOR]

The ability to select the necessary means for a familiar task while the task itself or the respective tools are out of sight suggests a rudimentary form of planning. Here we investigated if and how a non-specialized tool using bird, the Goffin's cockatoo, can prospectively or retrospectively select the functional tool in a decision-making task featuring two different types of apparatuses and their corresponding tools. Each apparatus could only be employed with one specific type of tool. Either the apparatus was presented and occluded prior to the presentation of the tools (prospective condition) or the tools were presented and occluded prior to the presentation of the apparatus (retrospective condition). Our results suggest the birds can prospectively but not retrospectively select the correct tool, paralleling previous research in tool using apes, and indicate at least simple forms of prospective selection in the tool use of a species distantly related to primates. [ABSTRACT FROM AUTHOR]

Rooks, Eurasian jays and NC crows have already solved the Aesop's fable paradigm, using stones to raise a water level to get a previously out of reach reward. Here we test kea parrots on their understanding of water displacement. In Experiment 1, they preferentially chose the water-filled tube over two solid substrates (sand, rocks) within 5 trials. In Experiment 2, they generalised to novel coloured substrates in the first trial. In Experiment 3, confronted with two water-filled tubes, one of which was made unsolvable by preventing the water from rising, none of the kea managed to solve the task. This suggests that their performance in Experiments 1 and 2 was reward association with the liquid-filled tube, without attendance to changes in water level. These results therefore provide no evidence of causal understanding of water displacement and highlight that such an understanding is not required for solving Aesop's Fable. [ABSTRACT FROM AUTHOR]

We can accomplish the same goal using different combinations of our body segments. This phenomenon is termed 'motor equivalence' (Lashley, 1930). A tool is an object detachable from the environment, that coupled to our body extents our capacity of exploring and changing the environment (Beck, 1980; cf. St Amant, & Horton, 2008). The process of the use of a tool has neurological implications, affording the incorporation of the tool physical properties in our neuromotor system (Maravita, & Iriki, 2004; Catela, 2007; Ferreira & Catela, 2012). Even with only one trial, reaching to a target with a light weight rod we do similar trajectories those formed without the rod (Lacquaniti, Socchting, & Terzuolo, 1982). With this paper, we intended to verify if kindergarten children would be able to perceive the affordance of rods with various lengths to reach and push a light ball into a target. The sample was composed by 13 kindergarten children (6 girls), with 3 years old. Informed consent and assent was obtained. Their arm was measured (27,8±2,3cm). Seven light rods with length differences between them of 7,5cm, starting at 22,5cm, till 67,5cm, were used; and the length of the intermediate rod (45cm) was summed to the individual arm length of the child, which was used to place him/her in front of a table with a light ball near him/her. Behind the ball there was a vertical target. So, the ball was in the extrapersonal space, i.e., the space outside the hand-reaching distance (Berti & Frassinetti, 2000); becoming in the personal space if the rod was provided, from the intermediate one till the longer one. Showing to the child one rod at a time (the child didn't touch the rod, only saw it in the hand of the experimenter), in an increasing or in a decreasing order of lengths, whose sequences where alternated among children, it was asked to him/her, for each rod, if he/she could push the ball to the target with that rod. After this condition, and for the rods where the child said that he/she could do it, the child had the opportunity to try to do it, and his/her actions were qualitatively analyzed. The Mann-Whitney test was used for intergroup comparisons and Cochran test (Q), followed by McNemar test (with Bonferroni correction), were used for intragroup comparisons, and, the Contingency coefficient was used for association between variables; for a level of significance of ,05; through the IBM-SPSS program, version 24. No significant differences were found between genders and rods' order of presentation. The results revealed that with the shortest rod (25,5cm) 46,15% of the children responded that they could, and with the following one (30cm), 53,85% also said it. For the rod with the length of 37,5cm, the affirmative answer rose to 76,92%; and for the intermediate rod stood at 69,23%. For the longer rods, values were 100% and 92,31%. Overall, there was a significant difference of positive answers between rods (Q (13,6) = 21,447, p<,002); however, no significant differences were found when paired comparisons were made. Because only with the intermediate rod a child would reach the ball, needing to totally stretch the arm, it meant that in the case of the shorter rods only if the child applied additional motor solutions he/she would reach the ball with the rod. In fact, for the shortest rod 66,7% of them extended the arm and rotated their shoulders, and 33,7% extended the arm and tilted the trunk. Arm extension with trunk forward tilt was a frequent motor solution, applied in the next rods (30cm-57,1%; 37,5cm and 45cm-40%; 52,5cm-61,5%), falling to 18,2% in the 60cm rod length, and 7,7% with the 67,5cm one. For the last two rods, the most frequent solution was elbow extension, with 72,7% of occurrences with the 60cm rod and 76,9% with the 67,5cm one. This study confirms that even before acting with the tool, the child has the capability to detect it affordances (cf. Gibson, 1979/1986), in order to use it in synergy with his/her own body' degrees of freedom (articulations of the elbow, of the trunk and of the hip). The children also revealed the capacity to incorporate the length of the rods in their actions (cf. Bongers, Michaels, & Smitsman, 2004; Bongers, Smitsman, & Michaels, 2004), exchanging from use of more degrees of freedom to less ones, as the rods became longer. As the rods became longer, the motor solutions have evolved always to the most economical solution, because extending the arm is less tiring than tilting the trunk; and, no child used only the movement of the trunk to reach the ball with the rod. So, children also detected the interplay of the affordance of the rod with their effectivities (cf. van Leeuwen, Smitsman, & van Leeuwen, 1994), because with some capacity of differentiation, they changed postural solutions according to rod length (cf. Bongers, 2001). Additionally, motor equivalence was also present, because different children have presented different solutions for the same rod length. If children with 3 years old do have the perceptual capacity to detect tool affordances and to adapt to changes in the environment, it is essential to promote perceptual-motor stimulation at the kindergarten, in order to ensure an enriched child development (cf. Smitsman, & Bongers, 2003). [ABSTRACT FROM AUTHOR]