The Experts below are selected from a list of 156 Experts worldwide ranked by ideXlab platform
Christian Rutz - One of the best experts on this subject based on the ideXlab platform.
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New Caledonian Crows afford invaluable comparative insights into human cumulative technological culture.
The Behavioral and brain sciences, 2020Co-Authors: Christian Rutz, Gavin R. HuntAbstract:The New Caledonian Crow may be the only non-primate species exhibiting cumulative technological culture. Its foraging tools show clear signs of diversification and progressive refinement, and it seems likely that at least some tool-related information is passed across generations via social learning. Here, we explain how these remarkable birds can help us uncover the basic biological processes driving technological progress.
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hook innovation boosts foraging efficiency in tool using Crows
Nature Ecology and Evolution, 2018Co-Authors: James J H St Clair, Shoko Sugasawa, Barbara Christina Klump, Caitlin Higgott, Nick Colegrave, Christian RutzAbstract:The New Caledonian Crow is the only non-human animal known to craft hooked tools in the wild, but the ecological benefit of these relatively complex tools remains unknown. Here, we show that Crows acquire food several times faster when using hooked rather than non-hooked tools, regardless of tool material, prey type and extraction context. This implies that small changes to tool shape can strongly affect energy-intake rates, highlighting a powerful driver for technological advancement.
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Preliminary observations of tool-processing behaviour in Hawaiian Crows Corvus hawaiiensis
Taylor & Francis Group, 2018Co-Authors: Barbara C. Klump, James J H St Clair, Bryce M. Masuda, Christian RutzAbstract:Very few animal species habitually make and use foraging tools. We recently discovered that the Hawaiian Crow is a highly skilled, natural tool user. Most captive adults in our experiment spontaneously used sticks to access out-of-reach food from a range of extraction tasks, exhibiting a surprising degree of dexterity. Moreover, many birds modified tools before or during deployment, and some even manufactured tools from raw materials. In this invited addendum article, we describe and discuss these observations in more detail. Our preliminary data, and comparisons with the better-studied New Caledonian Crow, suggest that the Hawaiian Crow has extensive tool-modification and manufacture abilities. To chart the full extent of the species’ natural tool-making repertoire, we have started conducting dedicated experiments where subjects are given access to suitable raw materials for tool manufacture, but not ready-to-use tools
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Discovery of species-wide tool use in the Hawaiian Crow
Nature, 2016Co-Authors: Christian Rutz, Shoko Sugasawa, Barbara C. Klump, Michael B Morrissey, Richard James, Lisa Komarczyk, Rosanna Leighton, Joshua Kramer, Saskia Wischnewski, James J H St ClairAbstract:Only a handful of bird species are known to use foraging tools in the wild^ 1 . Amongst them, the New Caledonian Crow ( Corvus moneduloides ) stands out with its sophisticated tool-making skills^ 2 , 3 . Despite considerable speculation, the evolutionary origins of this species’ remarkable tool behaviour remain largely unknown, not least because no naturally tool-using congeners have yet been identified that would enable informative comparisons^ 4 . Here we show that another tropical corvid, the ‘Alalā ( C. hawaiiensis ; Hawaiian Crow), is a highly dexterous tool user. Although the ‘Alalā became extinct in the wild in the early 2000s, and currently survives only in captivity^ 5 , at least two lines of evidence suggest that tool use is part of the species’ natural behavioural repertoire: juveniles develop functional tool use without training, or social input from adults; and proficient tool use is a species-wide capacity. ‘Alalā and New Caledonian Crows evolved in similar environments on remote tropical islands, yet are only distantly related^ 6 , suggesting that their technical abilities arose convergently. This supports the idea that avian foraging tool use is facilitated by ecological conditions typical of islands, such as reduced competition for embedded prey and low predation risk^ 4 , 7 . Our discovery creates exciting opportunities for comparative research on multiple tool-using and non-tool-using corvid species. Such work will in turn pave the way for replicated cross-taxonomic comparisons with the primate lineage, enabling valuable insights into the evolutionary origins of tool-using behaviour. A species-wide study shows that the Hawaiian Crow Corvus hawaiiensis is a highly proficient tool user, creating opportunities for comparative studies with tool-using New Caledonian Crows and other corvids. Birds in the Crow family are renowned for their cognitive abilities. The New Caledonian Crow Corvus moneduloides is well known for its ability to make and use foraging tools. Christian Rutz et al . show that it is not some lone outlier—it is now joined by another species from the Pacific, the Hawaiian Crow Corvus hawaiiensis , better known by its indigenous Hawaiian name 'Alalā. These birds naturally develop tool-using skills when young, and proficient tool use is a species-wide capacity. The authors can say this with confidence as the 'Alalā is extinct in the wild, and they were able to test 104 of the 109 surviving members of the species at the time, all in captivity. The research suggests that the technological skills of tropical Crows might be fostered by rather unusual ecological circumstances found on remote islands, such as reduced competition for embedded prey and low predation risk. The discovery of a second tool-using Crow species opens up exciting opportunities for comparative studies on animal tool use.
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tool bending in New Caledonian Crows
Royal Society Open Science, 2016Co-Authors: Christian Rutz, Shoko Sugasawa, Jessica Eva Megan Van Der Wal, Barbara Christina Klump, James J H St ClairAbstract:‘Betty’ the New Caledonian Crow astonished the world when she ‘spontaneously’ bent straight pieces of garden wire into hooked foraging tools. Recent field experiments have revealed that tool bending is part of the species9 natural behavioural repertoire, providing important context for interpreting Betty9s iconic wire-bending feat. More generally, this discovery provides a compelling illustration of how natural history observations can inform laboratory-based research into the cognitive capacities of non-human animals.
Russell D. Gray - One of the best experts on this subject based on the ideXlab platform.
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mental template matching is a potential cultural transmission mechanism for New Caledonian Crow tool manufacturing traditions
Scientific Reports, 2018Co-Authors: Sarah A. Jelbert, Russell D. Gray, Roger J Hosking, Adrian H TaylorAbstract:Cumulative cultural evolution occurs when social traditions accumulate improvements over time. In humans cumulative cultural evolution is thought to depend on a unique suite of cognitive abilities, including teaching, language and imitation. Tool-making New Caledonian Crows show some hallmarks of cumulative culture; but this claim is contentious, in part because these birds do not appear to imitate. One alternative hypothesis is that Crows’ tool designs could be culturally transmitted through a process of mental template matching. That is, individuals could use or observe conspecifics’ tools, form a mental template of a particular tool design, and then reproduce this in their own manufacture – a process analogous to birdsong learning. Here, we provide the first evidence supporting this hypothesis, by demonstrating that New Caledonian Crows have the cognitive capacity for mental template matching. Using a novel manufacture paradigm, Crows were first trained to drop paper into a vending machine to retrieve rewards. They later learnt that only items of a particular size (large or small templates) were rewarded. At test, despite being rewarded at random, and with no physical templates present, Crows manufactured items that were more similar in size to previously rewarded, than unrewarded, templates. Our results provide the first evidence that this cognitive ability may underpin the transmission of New Caledonian Crows’ natural tool designs.
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adaptive bill morphology for enhanced tool manipulation in New Caledonian Crows
Scientific Reports, 2016Co-Authors: Hiroshi Matsui, Gavin R. Hunt, Russell D. Gray, K Oberhofer, Naomichi Ogihara, Kevin J Mcgowan, Kumar Mithraratne, Takeshi Yamasaki, Ei Ichi IzawaAbstract:Early increased sophistication of human tools is thought to be underpinned by adaptive morphology for efficient tool manipulation. Such adaptive specialisation is unknown in nonhuman primates but may have evolved in the New Caledonian Crow, which has sophisticated tool manufacture. The straightness of its bill, for example, may be adaptive for enhanced visually-directed use of tools. Here, we examine in detail the shape and internal structure of the New Caledonian Crow’s bill using Principal Components Analysis and Computed Tomography within a comparative framework. We found that the bill has a combination of interrelated shape and structural features unique within Corvus, and possibly birds generally. The upper mandible is relatively deep and short with a straight cutting edge, and the lower mandible is strengthened and upturned. These novel combined attributes would be functional for (i) counteracting the unique loading patterns acting on the bill when manipulating tools, (ii) a strong precision grip to hold tools securely, and (iii) enhanced visually-guided tool use. Our findings indicate that the New Caledonian Crow’s innovative bill has been adapted for tool manipulation to at least some degree. Early increased sophistication of tools may require the co-evolution of morphology that provides improved manipulatory skills.
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modifications to the aesop s fable paradigm change New Caledonian Crow performances
PLOS ONE, 2014Co-Authors: Corina J. Logan, Sarah A. Jelbert, Alexis J. Breen, Russell D. Gray, Alex H. TaylorAbstract:While humans are able to understand much about causality, it is unclear to what extent non-human animals can do the same. The Aesop's Fable paradigm requires an animal to drop stones into a water-filled tube to bring a floating food reward within reach. Rook, Eurasian jay, and New Caledonian Crow performances are similar to those of children under seven years of age when solving this task. However, we know very little about the cognition underpinning these birds' performances. Here, we address several limitations of previous Aesop's Fable studies to gain insight into the causal cognition of New Caledonian Crows. Our results provide the first evidence that any non-human animal can solve the U-tube task and can discriminate between water-filled tubes of different volumes. However, our results do not provide support for the hypothesis that these Crows can infer the presence of a hidden causal mechanism. They also call into question previous object-discrimination performances. The methodologies outlined here should allow for more powerful comparisons between humans and other animal species and thus help us to determine which aspects of causal cognition are distinct to humans.
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Modifications to the Aesop’s Fable Paradigm Change New Caledonian Crow Performances
2014Co-Authors: Corina J. Logan, Sarah A. Jelbert, Alexis J. Breen, Russell D. Gray, Alex H. TaylorAbstract:While humans are able to understand much about causality, it is unclear to what extent non-human animals can do the same. The Aesop’s Fable paradigm requires an animal to drop stones into a water-filled tube to bring a floating food reward within reach. Rook, Eurasian jay, and New Caledonian Crow performances are similar to those of children under seven years of age when solving this task. However, we know very little about the cognition underpinning these birds ’ performances. Here, we address several limitations of previous Aesop’s Fable studies to gain insight into the causal cognition of New Caledonian Crows. Our results provide the first evidence that any non-human animal can solve the U-tube task and can discriminate between water-filled tubes of different volumes. However, our results do not provide support for the hypothesis that these Crows can infer the presence of a hidden causal mechanism. They also call into question previous object-discrimination performances. The methodologies outlined here should allow for more powerful comparisons between humans and other animal species and thus help us to determine which aspects of causal cognition are distinct t
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population genetic structure and colonisation history of the tool using New Caledonian Crow
PLOS ONE, 2012Co-Authors: Gavin R. Hunt, Russell D. Gray, Jawad Abdelkrim, Neil J GemmellAbstract:New Caledonian Crows exhibit considerable variation in tool making between populations. Here, we present the first study of the species’ genetic structure over its geographical distribution. We collected feathers from Crows on mainland Grande Terre, the inshore island of Toupeti, and the nearby island of Mare where it is believed birds were introduced after European colonisation. We used nine microsatellite markers to establish the genotypes of 136 Crows from these islands and classical population genetic tools as well as Approximate Bayesian Computations to explore the distribution of genetic diversity. We found that New Caledonian Crows most likely separate into three main distinct clusters: Grande Terre, Toupeti and Mare. Furthermore, Toupeti and Mare Crows represent a subset of the genetic diversity observed on Grande Terre, confirming their mainland origin. The genetic data are compatible with a colonisation of Mare taking place after European colonisation around 1900. Importantly, we observed (1) moderate, but significant, genetic differentiation across Grande Terre, and (2) that the degree of differentiation between populations on the mainland increases with geographic distance. These data indicate that despite individual Crows’ potential ability to disperse over large distances, most gene flow occurs over short distances. The temporal and spatial patterns described provide a basis for further hypothesis testing and investigation of the geographical variation observed in the tool skills of these Crows.
James J H St Clair - One of the best experts on this subject based on the ideXlab platform.
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hook innovation boosts foraging efficiency in tool using Crows
Nature Ecology and Evolution, 2018Co-Authors: James J H St Clair, Shoko Sugasawa, Barbara Christina Klump, Caitlin Higgott, Nick Colegrave, Christian RutzAbstract:The New Caledonian Crow is the only non-human animal known to craft hooked tools in the wild, but the ecological benefit of these relatively complex tools remains unknown. Here, we show that Crows acquire food several times faster when using hooked rather than non-hooked tools, regardless of tool material, prey type and extraction context. This implies that small changes to tool shape can strongly affect energy-intake rates, highlighting a powerful driver for technological advancement.
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Preliminary observations of tool-processing behaviour in Hawaiian Crows Corvus hawaiiensis
Taylor & Francis Group, 2018Co-Authors: Barbara C. Klump, James J H St Clair, Bryce M. Masuda, Christian RutzAbstract:Very few animal species habitually make and use foraging tools. We recently discovered that the Hawaiian Crow is a highly skilled, natural tool user. Most captive adults in our experiment spontaneously used sticks to access out-of-reach food from a range of extraction tasks, exhibiting a surprising degree of dexterity. Moreover, many birds modified tools before or during deployment, and some even manufactured tools from raw materials. In this invited addendum article, we describe and discuss these observations in more detail. Our preliminary data, and comparisons with the better-studied New Caledonian Crow, suggest that the Hawaiian Crow has extensive tool-modification and manufacture abilities. To chart the full extent of the species’ natural tool-making repertoire, we have started conducting dedicated experiments where subjects are given access to suitable raw materials for tool manufacture, but not ready-to-use tools
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Discovery of species-wide tool use in the Hawaiian Crow
Nature, 2016Co-Authors: Christian Rutz, Shoko Sugasawa, Barbara C. Klump, Michael B Morrissey, Richard James, Lisa Komarczyk, Rosanna Leighton, Joshua Kramer, Saskia Wischnewski, James J H St ClairAbstract:Only a handful of bird species are known to use foraging tools in the wild^ 1 . Amongst them, the New Caledonian Crow ( Corvus moneduloides ) stands out with its sophisticated tool-making skills^ 2 , 3 . Despite considerable speculation, the evolutionary origins of this species’ remarkable tool behaviour remain largely unknown, not least because no naturally tool-using congeners have yet been identified that would enable informative comparisons^ 4 . Here we show that another tropical corvid, the ‘Alalā ( C. hawaiiensis ; Hawaiian Crow), is a highly dexterous tool user. Although the ‘Alalā became extinct in the wild in the early 2000s, and currently survives only in captivity^ 5 , at least two lines of evidence suggest that tool use is part of the species’ natural behavioural repertoire: juveniles develop functional tool use without training, or social input from adults; and proficient tool use is a species-wide capacity. ‘Alalā and New Caledonian Crows evolved in similar environments on remote tropical islands, yet are only distantly related^ 6 , suggesting that their technical abilities arose convergently. This supports the idea that avian foraging tool use is facilitated by ecological conditions typical of islands, such as reduced competition for embedded prey and low predation risk^ 4 , 7 . Our discovery creates exciting opportunities for comparative research on multiple tool-using and non-tool-using corvid species. Such work will in turn pave the way for replicated cross-taxonomic comparisons with the primate lineage, enabling valuable insights into the evolutionary origins of tool-using behaviour. A species-wide study shows that the Hawaiian Crow Corvus hawaiiensis is a highly proficient tool user, creating opportunities for comparative studies with tool-using New Caledonian Crows and other corvids. Birds in the Crow family are renowned for their cognitive abilities. The New Caledonian Crow Corvus moneduloides is well known for its ability to make and use foraging tools. Christian Rutz et al . show that it is not some lone outlier—it is now joined by another species from the Pacific, the Hawaiian Crow Corvus hawaiiensis , better known by its indigenous Hawaiian name 'Alalā. These birds naturally develop tool-using skills when young, and proficient tool use is a species-wide capacity. The authors can say this with confidence as the 'Alalā is extinct in the wild, and they were able to test 104 of the 109 surviving members of the species at the time, all in captivity. The research suggests that the technological skills of tropical Crows might be fostered by rather unusual ecological circumstances found on remote islands, such as reduced competition for embedded prey and low predation risk. The discovery of a second tool-using Crow species opens up exciting opportunities for comparative studies on animal tool use.
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tool bending in New Caledonian Crows
Royal Society Open Science, 2016Co-Authors: Christian Rutz, Shoko Sugasawa, Jessica Eva Megan Van Der Wal, Barbara Christina Klump, James J H St ClairAbstract:‘Betty’ the New Caledonian Crow astonished the world when she ‘spontaneously’ bent straight pieces of garden wire into hooked foraging tools. Recent field experiments have revealed that tool bending is part of the species9 natural behavioural repertoire, providing important context for interpreting Betty9s iconic wire-bending feat. More generally, this discovery provides a compelling illustration of how natural history observations can inform laboratory-based research into the cognitive capacities of non-human animals.
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experimental resource pulses influence social network dynamics and the potential for information flow in tool using Crows
Nature Communications, 2015Co-Authors: James J H St Clair, Thomas B Ryder, Robert C Fleischer, Zackory T Burns, Elaine M Bettaney, Michael B Morrissey, Brian Otis, Richard James, Christian RutzAbstract:Social-network dynamics have profound consequences for biological processes such as information flow, but are notoriously difficult to measure in the wild. We used novel transceiver technology to chart association patterns across 19 days in a wild population of the New Caledonian Crow--a tool-using species that may socially learn, and culturally accumulate, tool-related information. To examine the causes and consequences of changing network topology, we manipulated the environmental availability of the Crows' preferred tool-extracted prey, and simulated, in silico, the diffusion of information across field-recorded time-ordered networks. Here we show that network structure responds quickly to environmental change and that novel information can potentially spread rapidly within multi-family communities, especially when tool-use opportunities are plentiful. At the same time, we report surprisingly limited social contact between neighbouring Crow communities. Such scale dependence in information-flow dynamics is likely to influence the evolution and maintenance of material cultures.
Alex Kacelnik - One of the best experts on this subject based on the ideXlab platform.
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Tool-related Cognition Tool-related Cognition in New Caledonian Crows
2014Co-Authors: Lucas A. Bluff, Christian Rutz, Alex A. S. Weir, Joanna H. Wimpenny, Alex KacelnikAbstract:The extent to which non-humans understand their physical world is controversial, due to conceptual and empirical difficul-ties. We examine the evidence for physical understanding in the remarkable tool-oriented behaviour of New Caledonian Crows, which make several types of tool in the wild and show prolific tool-related behaviour in captivity. We summarize our own research into the cognitive processes involved in tool behaviour in this species, and review comparable studies in other birds and primates. Our main laboratory findings are: tool-related behaviour emerges in juvenile Crows that had no opportunity to learn from others; adult Crows can make or select tools of the appropriate length or diameter for tasks; and one Crow, at least, can bend and unbend novel material to match task requirements. Although these observations are striking, they do not prove that this species is capable of understanding physical causality, as one cannot exclude explanations based on inherited proclivities, associative learning, and generalisation. Despite this, we argue that the conventional mechanisms become less likely as such observations accumulate. We conclude that while no adequate, non-verbal test for understanding exists, continued work with New Caledonian Crows will help us to ask the right questions. Our group has studied tool-oriented behaviour (TOB) in New Caledonian Crows (Corvus moneduloides) for the past six years (Figure 1). This followed the first systematic documentation of wild New Caledonian Crow behaviour b
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monocular tool control eye dominance and laterality in New Caledonian Crows
Current Biology, 2014Co-Authors: Antone Martinho, Zackory T Burns, Auguste Marie Philippa Von Bayern, Alex KacelnikAbstract:Summary Tool use, though rare, is taxonomically widespread, but morphological adaptations for tool use are virtually unknown [1]. We focus on the New Caledonian Crow (NCC, Corvus moneduloides ), which displays some of the most innovative tool-related behavior among nonhumans [2–6]. One of their major food sources is larvae extracted from burrows with sticks held diagonally [7] in the bill, oriented with individual, but not species-wide, laterality [8, 9]. Among possible behavioral [10] and anatomical adaptations for tool use [5, 11–15], NCCs possess unusually wide binocular visual fields (up to 60 ° ), suggesting that extreme binocular vision may facilitate tool use [5]. Here, we establish that during natural extractions, tool tips can only be viewed by the contralateral eye. Thus, maintaining binocular view of tool tips is unlikely to have selected for wide binocular fields; the selective factor is more likely to have been to allow each eye to see far enough across the midsagittal line to view the tool's tip monocularly [5, 16]. Consequently, we tested the hypothesis that tool side preference follows eye preference and found that eye dominance does predict tool laterality across individuals. This contrasts with humans' species-wide motor laterality and uncorrelated motor-visual laterality [17], possibly because bill-held tools are viewed monocularly and move in concert with eyes, whereas hand-held tools are visible to both eyes and allow independent combinations of eye preference and handedness. This difference may affect other models of coordination between vision and mechanical control, not necessarily involving tools.
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Tool-related cognition in New Caledonian Crows
2014Co-Authors: Christian Rutz, Alex Kacelnik, Alex A. S. Weir, Lucas A. Bluff, Joanna H. Wimpenny, Joanna HAbstract:The extent to which non-humans understand their physical world is controversial, due to conceptual and empirical difficulties. We examine the evidence for physical understanding in the remarkable tool-oriented behaviour of New Caledonian Crows, which make several types of tool in the wild and show prolific tool-related behaviour in captivity. We summarize our own research into the cognitive processes involved in tool behaviour in this species, and review comparable studies in other birds and primates. Our main laboratory findings are: tool-related behaviour emerges in juvenile Crows that had no opportunity to learn from others; adult Crows can make or select tools of the appropriate length or diameter for tasks; and one Crow, at least, can bend and unbend novel material to match task requirements. Although these observations are striking, they do not prove that this species is capable of understanding physical causality, as one cannot exclude explanations based on inherited proclivities, associative learning, and generalisation. Despite this, we argue that the conventional mechanisms become less likely as such observations accumulate. We conclude that while no adequate, non-verbal test for understanding exists, continued work with New Caledonian Crows will help us to ask the right questions. Our group has studied tool-oriented behaviour (TOB) in New Caledonian Crows (Corvus moneduloides) for the past six years (Figure 1). This followed the first systematic documentation of wild New Caledonian Crow behaviour b
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vocal culture in New Caledonian Crows corvus moneduloides
Biological Journal of The Linnean Society, 2010Co-Authors: Lucas A. Bluff, Alex Kacelnik, Christian RutzAbstract:While recent research suggests that some animal species may possess ‘cultural’ traditions, much of the current evidence for wild populations remains contentious. This is largely due to the difficulty of demonstrating a fundamental prerequisite for the existence of culture: social learning. As the only case where social learning has been demonstrated conclusively, and subsequently linked to spatial or temporal trait variation, avian vocal dialects are the best studied, and most widely accepted, form of animal culture. Here, we investigate the potential for vocal culture in one of the few animals for which material culture has been suggested: the New Caledonian Crow Corvus moneduloides. We show that this species: (1) possesses the capacity for social learning of vocalizations (experimental evidence in the form of a captive subject that reproduces human speech and other anthropogenic noises); and (2) exhibits significant large-scale, population-level variation in its vocalizations (cross-island playback experiments, with analyses controlling for a substantial set of potentially confounding variables). In combination, this provides strong evidence for the existence of ‘culture’ in these birds. More specifically, our findings reveal that the species exhibits sufficient social learning mechanisms, and within-population structuring, to generate and perpetuate cultural variation in at least one behavioural domain. This is a critical first step towards demonstrating cultural transmission in other behaviours, including tool manufacture and tool use, opening the door for the simultaneous investigation of vocal and material culture in a nonhuman species. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 101, 767–776.
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cognitive processes associated with sequential tool use in New Caledonian Crows
PLOS ONE, 2009Co-Authors: Joanna H. Wimpenny, Christian Rutz, Alex A. S. Weir, Lisa Clayton, Alex KacelnikAbstract:Background: Using tools to act on non-food objects—for example, to make other tools—is considered to be a hallmark of human intelligence, and may have been a crucial step in our evolution. One form of this behaviour, ‘sequential tool use’, has been observed in a number of non-human primates and even in one bird, the New Caledonian Crow (Corvus moneduloides). While sequential tool use has often been interpreted as evidence for advanced cognitive abilities, such as planning and analogical reasoning, the behaviour itself can be underpinned by a range of different cognitive mechanisms, which have never been explicitly examined. Here, we present experiments that not only demonstrate New tool-using capabilities in New Caledonian Crows, but allow examination of the extent to which Crows understand the physical interactions involved. Methodology/Principal Findings: In two experiments, we tested seven captive New Caledonian Crows in six tasks requiring the use of up to three different tools in a sequence to retrieve food. Our study incorporated several novel features: (i) we tested Crows on a three-tool problem (subjects were required to use a tool to retrieve a second tool, then use the second tool to retrieve a third one, and finally use the third one to reach for food); (ii) we presented tasks of different complexity in random rather than progressive order; (iii) we included a number of control conditions to test whether tool retrieval was goal-directed; and (iv) we manipulated the subjects’ pre-testing experience. Five subjects successfully used tools in a sequence (four from their first trial), and four subjects repeatedly solved the three-tool condition. Sequential tool use did not require, but was enhanced by, pre-training on each element in the sequence (‘chaining’), an explanation that could not be ruled out in earlier studies. By analyzing tool choice, tool swapping and improvement over time, we show that successful subjects did not use a random probing strategy. However, we find no firm evidence to support previous claims that sequential tool use demonstrates analogical reasoning or human-like planning. Conclusions/Significance: While the ability of subjects to use three tools in sequence reveals a competence beyond that observed in any other species, our study also emphasises the importance of parsimony in comparative cognitive science: seemingly intelligent behaviour can be achieved without the involvement of high-level mental faculties, and detailed analyses are necessary before accepting claims for complex cognitive abilities.
Sarah A. Jelbert - One of the best experts on this subject based on the ideXlab platform.
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mental template matching is a potential cultural transmission mechanism for New Caledonian Crow tool manufacturing traditions
Scientific Reports, 2018Co-Authors: Sarah A. Jelbert, Russell D. Gray, Roger J Hosking, Adrian H TaylorAbstract:Cumulative cultural evolution occurs when social traditions accumulate improvements over time. In humans cumulative cultural evolution is thought to depend on a unique suite of cognitive abilities, including teaching, language and imitation. Tool-making New Caledonian Crows show some hallmarks of cumulative culture; but this claim is contentious, in part because these birds do not appear to imitate. One alternative hypothesis is that Crows’ tool designs could be culturally transmitted through a process of mental template matching. That is, individuals could use or observe conspecifics’ tools, form a mental template of a particular tool design, and then reproduce this in their own manufacture – a process analogous to birdsong learning. Here, we provide the first evidence supporting this hypothesis, by demonstrating that New Caledonian Crows have the cognitive capacity for mental template matching. Using a novel manufacture paradigm, Crows were first trained to drop paper into a vending machine to retrieve rewards. They later learnt that only items of a particular size (large or small templates) were rewarded. At test, despite being rewarded at random, and with no physical templates present, Crows manufactured items that were more similar in size to previously rewarded, than unrewarded, templates. Our results provide the first evidence that this cognitive ability may underpin the transmission of New Caledonian Crows’ natural tool designs.
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modifications to the aesop s fable paradigm change New Caledonian Crow performances
PLOS ONE, 2014Co-Authors: Corina J. Logan, Sarah A. Jelbert, Alexis J. Breen, Russell D. Gray, Alex H. TaylorAbstract:While humans are able to understand much about causality, it is unclear to what extent non-human animals can do the same. The Aesop's Fable paradigm requires an animal to drop stones into a water-filled tube to bring a floating food reward within reach. Rook, Eurasian jay, and New Caledonian Crow performances are similar to those of children under seven years of age when solving this task. However, we know very little about the cognition underpinning these birds' performances. Here, we address several limitations of previous Aesop's Fable studies to gain insight into the causal cognition of New Caledonian Crows. Our results provide the first evidence that any non-human animal can solve the U-tube task and can discriminate between water-filled tubes of different volumes. However, our results do not provide support for the hypothesis that these Crows can infer the presence of a hidden causal mechanism. They also call into question previous object-discrimination performances. The methodologies outlined here should allow for more powerful comparisons between humans and other animal species and thus help us to determine which aspects of causal cognition are distinct to humans.
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Modifications to the Aesop’s Fable Paradigm Change New Caledonian Crow Performances
2014Co-Authors: Corina J. Logan, Sarah A. Jelbert, Alexis J. Breen, Russell D. Gray, Alex H. TaylorAbstract:While humans are able to understand much about causality, it is unclear to what extent non-human animals can do the same. The Aesop’s Fable paradigm requires an animal to drop stones into a water-filled tube to bring a floating food reward within reach. Rook, Eurasian jay, and New Caledonian Crow performances are similar to those of children under seven years of age when solving this task. However, we know very little about the cognition underpinning these birds ’ performances. Here, we address several limitations of previous Aesop’s Fable studies to gain insight into the causal cognition of New Caledonian Crows. Our results provide the first evidence that any non-human animal can solve the U-tube task and can discriminate between water-filled tubes of different volumes. However, our results do not provide support for the hypothesis that these Crows can infer the presence of a hidden causal mechanism. They also call into question previous object-discrimination performances. The methodologies outlined here should allow for more powerful comparisons between humans and other animal species and thus help us to determine which aspects of causal cognition are distinct t