Alice M I Auersperg

• University of Veterinary Medicine Vienna

Dunking behavior can be a foraging innovation in non-human animals in which food is dipped in a medium prior to consumption.1 Five functions of this behavior have previously been suggested (soaking, cleaning, flavoring, drowning, and transporting liquid).2,3,4,5,6,7,8 Although experimental reports exist,1,5,9,10,11 most dunking observations are ane...

[This corrects the article DOI: 10.1371/journal.pone.0253416.].

Utilising weight cues can improve the efficiency of foraging behaviours by providing information on nutritional value, material strength, and tool functionality. Attending to weight cues may also facilitate the optimisation of object transport. Though some animals’ ability to assess weight cues has been determined, research into whether they can ap...

The featured article by Sakurai and Tomonaga (2024) in this issue has set out to test to what extent dolphins can estimate relative differences between pairs of object numbers by echolocation. For this they used three consecutive experiments with multiple controls and compared their data statistically to existing data from visual experiments done o...

Many parrot species exhibit a high degree of limb lateralization on both the individual and species levels. In particular, the members of the cockatoo family are left-footed for food-holding at proportions reminiscent of right-handedness in humans. Here, we examine the limb lateralization of the Goffin’s cockatoo (Cacatua goffiniana), a tool-using...

School-aged children have consistently shown a surprising developmental lag when attempting to innovate solutions to tool use tasks, despite being capable of learning to solve these problems from a demonstrator. We suggest that this “innovation gap” arises from tool tasks with more complex spatial relations. Following Fragaszy and Mangalam’s new to...

Long-term memory — information retention over long timescales — can allow animals to retain foraging skills and efficiently respond to seasonal and changing environments. Most long-term memory research is with captive species, focusing on spatial, individual or object recognition, with less known about wild species and the retention of motor task a...

Goffin's cockatoos (Cacatua goffiniana) can solve a diverse set of mechanical problems, such as tool use, tool manufacture, and mechanical puzzles. However, the proximate mechanisms underlying this adaptive behavior are largely unknown. Similarly, engineering artificial agents that can as flexibly solve such mechanical puzzles is still a substantia...

Research continues to accumulate evidence that Goffin's cockatoos (Cacatua goffiniana) can solve wide sets of mechanical problems, such as tool use, tool manufacture, and solving mechanical puzzles. However, the proximate mechanisms underlying this adaptive behavior are largely unknown. In this study, we analyze how three Goffin's cockatoos learn t...

Comments on an article by Jay W. Schwartz , Kayleigh H. Pierson, and Alexander K. Reece (see record 2024-19488-001). In this issue, Schwartz et al. (2024) tackle the pitch rule in humans by testing to what extent we use pitch alone to judge emotional arousal across closely and distantly related animal species. The findings of Schwartz et al. open a...

Neophobia and neophilia can be lifesaving as they can facilitate foraging while avoiding predation or intoxication. We investigated the extent to which Goffin’s cockatoos (Cacatua goffiniana) exhibit ecollogically relevant and quantifiable neophobic responses toward specific object properties. Twelve cockatoos were presented with 12 novel objects g...

The study of animal behaviour and cognition would not be complete without investigations of wild, free-ranging individuals in their natural environment. However, direct observations of species living in dense habitats can be challenging, leading many studies to focus on attracting target species to pre-selected, monitored locations baited with food...

Foraging innovations in animals involving the processing of resources that are already edible in an unprocessed state, yet of improved quality in a processed state, are rare but important to study the evolution of food preparation. Here, we present the first scientific report of food dunking behaviours in parrots by Goffin's cockatoos, a model spec...

Innovation (i.e., a new solution to a familiar problem, or applying an existing behavior to a novel problem) plays a fundamental role in species’ ecology and evolution. It can be a useful measure for cross-group comparisons of behavioral and cognitive flexibility and a proxy for general intelligence. Among birds, experimental studies of innovation...

Prikrylová et al. (see record 2023-79461-001) contribute a paper to this issue in which they tested two-dimensional individual recognition of familiar subjects in African gray parrots. They not only tested familiar individual recognition per se but also the effect of manipulating individual and combined features in the head and the body of their st...

Tanimbar corellas, an important model in comparative cognition research, are endemic to the Tanimbar Islands, Indonesia, but were also introduced to several other locations with a tropical climate. Introduced psittacines offer valuable opportunities to test hypotheses at large temporal and spatial scales, such as geographic distribution of behaviou...

The use of tool sets constitutes one of the most elaborate examples of animal technology, and reports of it in nature are limited to chimpanzees and Goffin's cockatoos. Although tool set use in Goffin's was only recently discovered, we know that chimpanzees flexibly transport tool sets, depending on their need. Flexible tool set transport can be co...

Psittacines, along with corvids, are commonly referred to as ‘feathered apes’ due to their advanced cognitive abilities. Until rather recently, the research effort on parrot cognition was lagging behind that on corvids, however current developments show that the number of parrot studies is steadily increasing. In 2018, M. L. Lambert et al. provided...

The ability to gain information from one situation, acquire new skills and/or perfect existing ones, and subsequently apply them to a new situation is a key element in behavioural flexibility and a hallmark of innovation. A flexible agent is expected to store these skills and apply them to contexts different from that in which learning occurred. Go...

We want to understand how animals can learn to solve complex tasks. To achieve this, it makes sense to first hypothesize learning models and then compare these models to real biological learning data. But how to perform such a comparison is still unclear. We propose that yoking is an important component to such an analysis. In yoking, two agents ar...

The Goffin’s cockatoo (Goffin) is known for its advanced cognitive skills in the technical domain and the ability to innovate tool use in captivity. However, until recently, there were little data on the wildlife ecology of this species. Recent fieldwork in its natural habitat, the remote Tanimbar Islands in Indonesia, revealed that wild Goffins co...

Composite tool use (using more than one tool simultaneously to achieve an end) has played a significant role in the development of human technology. Typically, it depends on a number of specific and often complex spatial relations and there are thus very few reported cases in non-human animals (e.g., specific nut-cracking techniques in chimpanzees...

Despite countless anecdotes and the historical significance of insight as a problem solving mechanism, its nature has long remained elusive. The conscious experience of insight is notoriously difficult to trace in non-verbal animals. Although studying insight has presented a significant challenge even to neurobiology and psychology, human neuroimag...

Paying attention to weight is important when deciding upon an object's efficacy or value in various contexts (e.g. tool use, foraging). Proprioceptive discrimination learning, with objects that differ only in weight, has so far been investigated almost exclusively in primate species. Here, we show that while Goffin's cockatoos learn faster when add...

The use of different tools to achieve a single goal is considered unique to human and primate technology. To unravel the origins of such complex behaviors, it is crucial to investigate tool use that is not necessary for a species’ survival. These cases can be assumed to have emerged innovatively and be applied flexibly, thus emphasizing creativity...

Novel problems often partially overlap with familiar ones. Some features match the qualities of previous situations stored in long-term memory and therefore trigger their retrieval. Using relevant, while inhibiting irrelevant, memories to solve novel problems is a hallmark of behavioral flexibility in humans and has recently been demonstrated in gr...

Flexible targeted helping is considered an advanced form of prosocial behavior in hominoids, as it requires the actor to assess different situations that a conspecific may be in, and to subsequently flexibly satisfy different needs of that partner depending on the nature of those situations. So far, apart from humans such behaviour has only been ex...

Tool use research has suffered from a lack of consistent theoretical frameworks. There is a plethora of tool use definitions and the most widespread ones are so inclusive that the behaviors that fall under them arguably do not have much in common. The situation is aggravated by the prevalence of anecdotes, which have played an undue role in the lit...

Although several nonhuman animals have the ability to recognize and match templates in computerized tasks, we know little about their ability to recall and then physically manufacture specific features of mental templates. Across three experiments, Goffin cockatoos (Cacatua goffiniana), a species that can use tools in captivity, were exposed to two...

Goffin’s cockatoos, a parrot species endemic to the Tanimbar Islands in Indonesia, demonstrate remarkable cognitive skills across various technical tasks. These neophilic extractive foragers explore objects with their beak and feet, and are skilled in several modes of tool use. In this study, we confronted the animals for the first time with a vert...

Complex novel tasks are often used in animal cognition research to allow discrimination between various learning mechanisms. Successful performance relies on the capacity to identify informational cues from features in the environment. Additionally, observational learning is often considered more beneficial for survival than individual learning. De...

The ability to innovate, i.e., to exhibit new or modified learned behaviours, can facilitate adaptation to environmental changes or exploiting novel resources. We hereby introduce a comparative approach for studying innovation rate, the ‘Innovation Arena’ (IA), featuring the simultaneous presentation of 20 interchangeable tasks, which subjects enco...

Allogrooming in primates serves not only a hygienic function, but also plays a crucial role in maintaining strong affiliative bonds between group members, which in turn, underpin the emergence of cooperative behavior. In contrast, although allopreening occurs in many avian species, we know little about its social functions. Our study addresses this...

One hallmark in the evolution of cooperation is the ability to evaluate one's own payoff for a task against that of another person. To trace its evolutionary history, there has recently been a surge in comparative studies across different species. In non‐human animals, evidence of inequity aversion has so far been identified in several primate spec...

Parrots are renowned for their intelligence and ability to imitate human speech ever since they have been kept as pets. Despite of impressive pioneering work on the cognitive abilities of parrots, research on parrot cognition has only recently gained momentum, probably given the new wave of interest in possible convergent evolution of complex cogni...

Making economic decisions in a natural foraging situation that involves the use of tools may require an animal to consider more levels of relational complexity than merely deciding between an immediate and a delayed food option. We used the same method previously used with Goffin´s cockatoos to investigate the orangutans’ flexibility for making the...

Number of correct trials out of a total of 12 trials for each condition in the QAT for each individual. Binomial probabilities: * = p<0.05 (10/12 correct), ** = p<0.01 (11/12 correct); *** = p<0.001 (12/12 correct). (PDF)

Number of correct trials out of a total of 12 trials for each condition in the MT for each individual. Binomial probabilities: * = p<0.05 (10/12 correct), ** = p<0.01 (11/12 correct); *** = p<0.001 (12/12 correct). (PDF)

Results of the paired Wilcoxon tests for the first and last six trials of each condition for each test (n = 6). (PDF)

Number of correct trials out of a total of 12 trials for each condition in the TSQAT for each individual. Binomial probabilities: * = p<0.05 (10/12 correct), ** = p<0.01 (11/12 correct); *** = p<0.001 (12/12 correct). (PDF)

Results of the paired Wilcoxon tests for subjects´ performance in the ball- and stick- apparatus condition for each condition and for each test (n = 6). (PDF)

Results of the preference tests in percent (%) including all combinations (a = apple, g = grape, p = banana pellet, r = rusk; TPF = third preferred food, MPF = most preferred food). Preference test 1 was conducted before subjects entered the test, Preference test 4 was conducted after all subjects had received all test trials. Preference test 2 &3...

Names, sex and year of birth and rearing history of the six orangutans (Pongo abelii). (PDF)

Number of correct trials out of a total of 12 trials for each condition in the TST for each individual. Binomial probabilities: * = p<0.05 (10/12 correct), ** = p<0.01 (11/12 correct); *** = p<0.001 (12/12 correct). (PDF)

Number of correct trials out of a total of 12 trials for each condition in the TFT for each individual. Binomial probabilities: * = p<0.05 (10/12 correct), ** = p<0.01 (11/12 correct); *** = p<0.001 (12/12 correct). (PDF)

Experimental work on captive Goffin’s cockatoos (Cacatua goffiniana) has highlighted the remarkable cognitive abilities of this species. However, little is known about its behavior in the natural habitat on the Tanimbar Archipelago in Indonesia. In order to fully understand the evolutionary roots leading to cognitively advanced skills, such as mult...

Betty the crow astonished the scientific world as she spontaneously crafted hook-tools from straight wire in order to lift a basket out of vertical tubes. Recently it was suggested that this species' solution was strongly influenced by predispositions from behavioural routines from habitual hook-tool manufacture. Nevertheless, the task became a par...

The ability to innovatively use or even manufacture different tools depending on a current situation can be silhouetted against examples of stereotyped, inborn tool use/manufacture and is thus often associated to advanced cognitive processing. In this study we confronted non-specialized, yet innovative tool making birds, Goffin’s cockatoos (Cacatua...

Raw data: Contains the data obtained for the experiments in Microsoft excel. (XLSX)

Supplementary information: Contains details of both the training procedure as well as the results in Microsoft word. (DOCX)

The construction of novel compound tools through assemblage of otherwise non-functional elements involves anticipation of the affordances of the tools to be built. Except for few observations in captive great apes, compound tool construction is unknown outside humans, and tool innovation appears late in human ontogeny. We report that habitually too...

When tested under laboratory conditions, Goffin’s cockatoos (Cacatua goffiniana) demonstrate numerous sophisticated cognitive skills. Most importantly, this species has shown the ability to manufacture and use tools. However, little is known about the ecology of these cockatoos, endemic to the Tanimbar Islands in Indonesia. Here we provide first in...

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 feat...

So far only one bird species, a corvid, passed the mark test for mirror self-recognition (MSR) although the results have been questioned. We examined the capacity for MSR in another large-brained avian taxon, parrots, with keas ( Nestor notabilis ) and Goffin’s cockatoos ( Cacatua goffini ). After several weeks of mirror habituation, they were subj...

In captivity, the Goffin’s cockatoo (Cacatua goffiniana) has shown the capacity for flexible tool use and manufacture to a degree that rivals some habitually tool using birds. Although these skills make it an important avian model species for studying physical cognition, there are no scientific records of this species using objects as tools in the...

The ability to move an object in alignment to a surface develops early in human ontogeny. However, aligning not just your own body but also the object itself in relation to a surface with a specific shape requires using landmarks rather than the own body as a frame of reference for orientation. The ability to do so is considered important in the de...

The spontaneous crafting of hook-tools from bendable material to lift a basket out of a vertical tube in corvids has widely been used as one of the prime examples of animal tool innovation. However, it was recently suggested that the animals' solution was hardly innovative but strongly influenced by predispositions from habitual tool use and nest b...

Play behaviour may be subdivided into social play, locomotor play and object play. Object play has been proposed to constitute an important factor in developing skills concerned with physical problem solving. Especially tool using species seem to benefit from object play during their ontogeny. However, object play is not easily distinguished from e...

Exploration (interacting with objects to gain information) and neophobia (avoiding novelty) are considered independent traits shaped by the socio-ecology of a given species. However, in the literature it is often assumed that neophobia inhibits exploration. Here, we investigate how different approaches to novelty (fast or slow) determine the time a...

The cognitive abilities of birds are remarkable: hummingbirds integrate spatial and temporal information about food sources, day-old chicks have a sense of numbers, parrots can make and use tools, and ravens have sophisticated insights in social relationships. This volume describes the full range of avian cognitive abilities, the mechanisms behind...

Tool use in animals can be costly as foraging tools need to be actively searched for or manufactured. Consequently, some habitually tool-using species keep their tools safe and ‘recycle’ them for further use. We tested the Indonesian Goffin's cockatoo, a parrot with the capacity but no apparent adaptive specialization for tool use to investigate ho...

Innovative tool manufacture is rare and hard to isolate in animals. We show that an Indonesian generalist parrot, the Goffin's cockatoo, can flexibly and spontaneously transfer the manufacture of stick-type tools across three different materials. Each material required different manipulation patterns, including substrates that required active sculp...

Different types of social relationships can influence individual learning strategies in structured groups of animals. Studies on a number of avian species have suggested that local and/or stimulus enhancement are important ingredients of the respective species’ exploration modes. Our aim was to identify the role of enhancement during object manipul...

Decisions involving the use of tools may require an agent to consider more levels of relational complexity than merely deciding between an immediate and a delayed option. Using a new experimental approach featuring two different types of tools, two apparatuses as well as two different types of reward, we investigated the Goffin cockatoos’ ability t...

Unusual niches as well as unpredictable or seasonal resources foster a broader spectrum of foraging techniques and often promote flexibility and physical innovations. This may lead to an increase in technical abilities, including enhanced cause-effect exploitation, the capacity to distinguish between functional and nonfunctional object properties a...

Inference by exclusion, the ability to base choices on the systematic exclusion of alternatives, has been studied in many nonhuman species over the past decade. However, the majority of methodologies employed so far are hard to integrate into a comparative framework as they rarely use controls for the effect of neophilia. Here, we present an improv...

The playful (i.e., not overtly functional) combination of objects is considered a potential ontogenetic and phylogenetic precursor of technical problem solving abilities, as it may lead to affordance learning and honing of mechanical skills. We compared such activities in 6 avian species: 3 psittaciforms (black-headed caiques, red-shouldered macaws...

In primates, complex object combinations during play are often regarded as precursors of functional behavior. Here we investigate combinatory behaviors during unrewarded object manipulation in seven parrot species, including kea, African grey parrots and Goffin cockatoos, three species previously used as model species for technical problem solving....

Tool use can be inherited, or acquired as an individual innovation or by social transmission. Having previously reported individual innovative tool use and manufacture by a Goffin cockatoo, we used the innovator (Figaro, a male) as a demonstrator to investigate social transmission. Twelve Goffins saw either demonstrations by Figaro, or 'ghost' cont...

Word File containing 1) supplementary information on subjects, 2) supplementary details on individual insertion techniques, 3) Online links to Movie files for Movie S1 & S2, 4) Supplementary individual data for social learning experiment, 5) Images of all manufactured material during manufacture experiment

The ability to represent hidden objects plays an important role in the survival of many species. In order to provide an inclusive synopsis of the current benchmark tasks used to test object permanence in animals for a psittacine representative, we tested eight Goffin cockatoos (Cacatua goffini) on Stages 3-6 of Piagetian object permanence as well a...