Tool Use Abilities Research Articles

Different ways of evolving tool-using brains in teleosts and amniotes

In mammals and birds, tool-using species are characterized by their relatively large telencephalon containing a higher proportion of total brain neurons compared to other species. Some teleost species in the wrasse family have evolved tool-using abilities. In this study, we compared the brains of tool-using wrasses with various teleost species. We show that in the tool-using wrasses, the telencephalon and the ventral part of the forebrain and midbrain are significantly enlarged compared to other teleost species but do not contain a larger proportion of cells. Instead, this size difference is due to large fiber tracts connecting the dorsal part of the telencephalon (pallium) to the inferior lobe, a ventral mesencephalic structure absent in amniotes. The high degree of connectivity between these structures in tool-using wrasses suggests that the inferior lobe could contribute to higher-order cognitive functions. We conclude that the evolution of non-telencephalic structures might have been key in the emergence of these cognitive functions in teleosts.

Left anterior supramarginal gyrus activity during tool use action observation after extensive tool use training.

The advanced use of complex tools is considered a primary characteristic of human evolution and technological advancement. However, questions remain regarding whether humans possess unique underlying brain networks that support advanced tool-using abilities. Specifically, previous studies have demonstrated the presence of a structurally and functionally unique region in the left anterior supramarginal gyrus (aSMG), that is consistently active during tool use action observation. This region has been proposed as a primary hub for integrating semantic and technical information to form action plans with tools. However, it is still largely unknown how tool use motor learning affects left aSMG activation or connectivity with other brain regions. To address this, participants with little experience using chopsticks observed an experimenter using chopsticks to perform a novel task while undergoing two functional magnetic resonance imaging (fMRI) scans. Between the scans, participants underwent four weeks of behavioral training where they learned to use chopsticks and achieve proficiency in the observed task. Results demonstrated a significant change in effective connectivity between the left aSMG and the left anterior intraparietal sulcus (aIPS), a region involved in object affordances and planning grasping actions. These findings suggest that during unfamiliar tool use, the left aSMG integrates semantic and technical information to communicate with regions involved with grasp selection, such as the aIPS. This communication then allows appropriate grasps to be planned based on the physical properties of the objects involved and their potential interactions.

Language as a Tool: Motor Proficiency Using a Tool Predicts Individual Linguistic Abilities.

Different disciplines converge to trace language evolution from motor skills. The human ability to use tools has been advocated as a fundamental step toward the emergence of linguistic processes in the brain. Neuropsychological and neuroimaging research has established that linguistic functions and tool-use are mediated by partially overlapping brain networks. Yet, scholars still theoretically debate whether the relationship between tool-use and language is contingent or functionally relevant, since empirical evidence is critically missing. Here, we measured both linguistic production and tool-use abilities in the same participants, as well as manual and linguistic motor skills. A path analysis ruling out unspecific contributions from manual or linguistic motor skills, showed that motor proficiency using a tool lawfully predicts differences in individual linguistic production. In addition, more complex tool-use reveals stronger association between linguistic production and tool mastery. These findings establish the existence of shared cognitive processes between tool-use and language.

Proprioception Is Necessary for Body Schema Plasticity: Evidence from a Deafferented Patient.

The ability of using a large variety of tools is important in our daily life. Behind human tool-use abilities lays the brain capacity to incorporate tools into the body representation for action (Body Schema, BS), thought to rely mainly on proprioceptive information. Here, we tested whether tool incorporation is possible in absence of proprioception by studying a patient with right upper-limb deafferentation. We adopted a paradigm sensitive to changes of the BS and analyzed the kinematics of free-hand movements before and after tool-use, in three sessions over a period of 2 years. In the first session, before tool-use, the kinematics of the deafferented hand was disrupted. Similarly, the first movements with the tool (a mechanical grabber elongating the arm by ~40 cm) showed an abnormal profile that tended to normalize at the end of the session. Subsequent free-hand movements were also normalized. At session 2, 6 months later, the patient exhibited normal free-hand kinematic profiles, additionally showing changes in grasping kinematics after tool-use, but no sign of tool incorporation. A follow-up 2 years later, further confirmed the normalized kinematic profile but the absence of tool incorporation. This first description of tool-use in absence of proprioception shows the fundamental role of proprioception in the update of the BS. These results provide an important further step in understanding human motor control and have implications for future development of rehabilitation programs for patients with sensory deficits.

Young children spontaneously invent wild great apes' tool-use behaviours.

The variety and complexity of human-made tools are unique in the animal kingdom. Research investigating why human tool use is special has focused on the role of social learning: while non-human great apes acquire tool-use behaviours mostly by individual (re-)inventions, modern humans use imitation and teaching to accumulate innovations over time. However, little is known about tool-use behaviours that humans can invent individually, i.e. without cultural knowledge. We presented 2- to 3.5-year-old children with 12 problem-solving tasks based on tool-use behaviours shown by great apes. Spontaneous tool use was observed in 11 tasks. Additionally, tasks which occurred more frequently in wild great apes were also solved more frequently by human children. Our results demonstrate great similarity in the spontaneous tool-use abilities of human children and great apes, indicating that the physical cognition underlying tool use shows large overlaps across the great ape species. This suggests that humans are neither born with special physical cognition skills, nor that these skills have degraded due to our species’ long reliance of social learning in the tool-use domain.

Bonobos use a range of tools like early humans

Bonobos can be just as handy as chimpanzees. In fact, bonobos' tool-using abilities look a lot like those of early humans, suggesting that observing them could teach anthropologists about how one's own ancestors evolved such skills. Until now, bonobos have been more renowned for their free and easy sex lives than their abilities with tools.

Tool-use and instrumental learning in the Eurasian jay (Garrulus glandarius)

Recent research with Rooks has demonstrated impressive tool-using abilities in captivity despite this species' classification as a non-tool-user in the wild. Here, we explored whether another non-tool-using corvid, the Eurasian Jay, would be capable of similar feats and investigated the relative contributions of causal knowledge and instrumental conditioning to the birds' performance on the tasks. Five jays were tested on a variety of tasks involving water displacement. Two birds reliably interacted with the apparatuses. In these tasks, both birds showed a preference for inserting stones into a tube containing liquid over a tube containing a solid or a baited 'empty' tube and also for inserting sinkable items over non-sinkable items into a tube of water. To investigate the contribution of instrumental conditioning, subjects were then tested on a series of tasks in which different cues were made available. It was found that, in the absence of any apparent causal cues, these birds showed a clear preference for the rewarded tube when the food incrementally approached with every stone insertion, but not when it simply "appeared" after the correct number of stone insertions. However, it was found that subjects did not prefer to insert stones into a tube rewarded by the incremental approach of food if the available causal cues violated the expectations created by existing causal knowledge (i.e. were counter-intuitive). An analysis of the proportion of correct and incorrect stone insertions made in each trial across tasks offering different types of information revealed that subjects were substantially more successful in experiments in which causal cues were available, but that rate of learning was comparable in all experiments. We suggest that these results indicate that Eurasian jays use the incremental approach of the food reward as a conditioned reinforcer allowing them to solve tasks involving raising the water level and that this learning is facilitated by the presence of causal cues.

Complex tool sets for honey extraction among chimpanzees in Loango National Park, Gabon

Homo faber was once proposed as a label for humans specifically to highlight their unique propensity for tool use. However, new observations on complex tool use by the chimpanzees of Loango National Park, Gabon, expand our knowledge about tool-using abilities in Pan troglodytes. Chimpanzees in Loango, when using tools to extract honey from three types of bee nests, were observed to regularly use three- to five-element tool sets. In other words, different types of tools were used sequentially to access a single food source. Such tool sets included multi-function tools that present typical wear for two distinct uses. In addition, chimpanzees exploited underground bee nests and used ground-perforating tools to locate nest chambers that were not visible from the ground surface. These new observations concur with others from Central African chimpanzees to highlight the importance of honey extraction in arguments favoring the emergence of complex tool use in hominoids, including different tool types, expanded tool sets, multifunction tools, and the exploitation of underground resources. This last technique requires sophisticated cognitive abilities concerning unseen objects. A sequential analysis reveals a higher level of complexity in honey extraction than previously proposed for nut cracking or hunting tools, and compares with some technologies attributed to early hominins from the Early and Middle Stone Age. A better understanding of similarities in human and chimpanzee tool use will allow for a greater understanding of tool-using skills that are uniquely human.

Tool use in wild spider monkeys (Ateles geoffroyi)

Tool use has been observed in a variety of primate species, including both New and Old World monkeys. However, such reports mainly address the most prodigious tool users and frequently limit discussions of tool-using behavior to a foraging framework. Here, we present observations of novel and spontaneous tool use in wild black-handed spider monkeys (Ateles geoffroyi), where female spider monkeys used detached sticks in a self-directed manner. We introduce factors to explain Ateles tool-using abilities and limitations, and encourage the synthesis of relevant research in order to gain insight into the cognitive abilities of spider monkeys and the evolution of tool-using behaviors in primates.

Continuing Investigations into the Stone Tool-making and Tool-using Capabilities of a Bonobo (Pan paniscus)

A long-term collaborative study by palaeolithic archaeologists and cognitive psychologists has continued in its investigations into the stone tool-making and tool-using abilities of a captive bonobo (a 180 pound male, named Kanzi, aged 12 years at the time of experiments reported here). A major focus of this study has been examination of the lithic reduction strategy over time and detailed analysis of the artefacts Kanzi has produced in 2 years of experimentation since our original report. Kanzi has exhibited marked improvement in his stone-working skills, although to date the artefacts he has produced still contrast with early hominid-produced artefacts in a number of attributes. Statistical analysis revealed that Kanzi is clearly preferentially selecting larger, heavier pieces of debitage (flakes and fragments) for use as tools.

Pan the Tool-Maker: Investigations into the Stone Tool-Making and Tool-Using Capabilities of a Bonobo ( Pan paniscus)

Beginning in May 1990, a long-term collaborative investigation between palaeolithic archaeologists and cognitive psychologists has focused upon the stone tool-making and tool-using abilities of a captive bonobo ( Pan paniscus). To date, this bonobo (named Kanzi) has acquired the basic skills required to produce usable flakes and fragments by hard-hammer percussion (as well as by his own innovation of throwing), although his skills in flaking stone are not yet as well developed as those exhibited by the earliest known tool-making hominids of the Oldowan industry. This research strategy allows direct comparisons and contrasts to be made between the products of modern human stone tool-makers, prehistoric proto-human tool-makers and non-human primates that have not evolved a flaked stone technology in the wild. This enables us to investigate what possible cognitive and biomechanical conditions of pre-adaptation for lithic technology may be present in extant apes. The bonobo's stone tool-making abilities are compared to those evident among early hominids in order to understand the complexities of this derived behaviour pattern in the earliest stone tool-makers. The possible evolutionary implications of this study are discussed.

Fossil primate hands: A review and an evolutionary inquiry emphasizing early forms

The paleontological evidence pertaining to the evolution of the modern diversity in structure and function of primate hands is reviewed. A reconstructed digit ofPlesiadapis shows characters and functional capacities typical of an arboreal way of life. In euprimates, we describe the strepsirhine morphotype hand, characterized by a relatively high degree of pollical divergence, features of the ulnocarpal articulation that imply an enhanced capacity for ulnar deviation, and relatively long digits; this hand is specialized for grasping. Hand remains ofSmilodectes, Adapis and a Messel adapiform reveal a remarkable diversity in carpal structure achieved in these Eocene adapiforms, due to differing locomotor evolutionary pathways. The subfossil lemuriformsMegaladapis andPalaeopropithecus both show stereotyped (but different) grasping capabilities. The simiiform morphotype hand combines a relatively low degree of pollical divergence, features of the ulnocarpal articulation that imply a limited capacity for ulnar deviation, and relatively long metacarpals and short digits. This type of hand anatomy is mechanically well-suited to arboreal palmigrade quadrupedalism. The hands ofPliopithecus andMesopithecus are generally monkey-like.Oreopithecus' hand fits with its presumed suspensory habits. The hand ofProconsul suggests palmigrade quadrupedalism and climbing.Australopithecus afarensis' hand remains primarily a branch-grasping organ, with indications of enhanced manipulatory abilities.Homo habilis andParanthropus robustus illustrate two lines of increased tool-use abilities. The euprimate morphotype hand was elongated, had a short carpus and limited mobility, but the corresponding locomotor mode remains speculative. Considerations on hand evolution in some living primate groups are included in the final summary of hand evolution in primates.

HUMAN PERFECTIBILITY

The author contends that, while understanding the role of DNA in human evolution and development is an exciting challenge for biology, it is not likely to lead to direct methods of increasing human perfectibility. The interaction of DNA with its immediate cellular environment as well as with the broader social environment is crucial and infinitely complex. Rose discusses how developmental and evolutionary biology both tend to ignore the active part an organism plays in changing its environment. The human genome makes possible the brain and the social and tool-using abilities which enable people to "transcend the limits apparently set by that very genome." Accordingly, techniques such as in vitro fertilization, gene therapy, and sperm banks will have a marginal effect on human evolution since DNA is subject to an almost infinitely varying set of environments.

The history and modern development of the art of interchangeable construction in mechanism

Beginning in May 1990, a long-term collaborative investigation between palaeolithic archaeologists and cognitive psychologists has focused upon the stone tool-making and tool-using abilities of a captive bonobo (Pan paniscus). To date, this bonobo (named Kanzi) has acquired the basic skills required to produce usable flakes and fragments by hard-hammer percussion (as well as by his own innovation of throwing), although his skills in flaking stone are not yet as well developed as those exhibited by the earliest known tool-making hominids of the Oldowan industry. This research strategy allows direct comparisons and contrasts to be made between the products of modern human stone tool-makers, prehistoric proto-human tool-makers and non-human primates that have not evolved a flaked stone technology in the wild. This enables us to investigate what possible cognitive and biomechanical conditions of pre-adaptation for lithic technology may be present in extant apes. The bonobo's stone tool-making abilities are compared to those evident among early hominids in order to understand the complexities of this derived behaviour pattern in the earliest stone tool-makers. The possible evolutionary implications of this study are discussed.