Are kea prosocial?

Prosociality and reciprocity according to parental status, communication, and personality in domestic canaries (Serinus canaria)

Prosociality (behaviours that benefit to a recipient without necessarily involving a cost to the actor) has recently been shown to exist in various taxa, including birds. Studies on prosociality in primates found that prosocial tendencies of the subject could be related to sex and parental care, communication from the recipient, cognitive abilities and personality. To investigate the existence of such associations on birds, we conducted a Prosocial Choice Task with domestic canaries (Serinus canaria). In our experiment, the subject could choose between three options: a prosocial, a selfish, and a null option (with no cost for the subject). We also conducted a food sharing experiment and measured several personality traits. Our results highlighted high levels of prosociality and a tendency to reciprocity among reproductive mates. We found a higher propensity to be prosocial in nulliparous individuals than in individuals that have previously been parents, but better sharing abilities in parents than in nulliparous individuals. When they were recipient, parents also used communication more efficiently than nulliparous subjects. Data suggest that parental expertise could enhance subjects' skills in eliciting prosociality. We also highlighted some interaction between prosociality, learning abilities, and some personality traits, proactive individuals being fast learners and more prosocial, while reactive individuals being slow learners and more reciprocal. Our results suggest that prosociality and reciprocity could be linked to personality and cognitive abilities, and that it might be interesting to consider them as parts of individual's cognitive style.

Recent developments in parrot cognition: a quadrennial update

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 a comprehensive review on the status of the most important work done so far in parrot and corvid cognition. Nevertheless, only a little more than 4 years after this publication, more than 50 new parrot studies have been published, some of them chartering completely new territory. On the 25th anniversary of Animal Cognition we think this warrants a detailed review of parrot cognition research over the last 4 years. We aim to capture recent developments and current trends in this rapidly expanding and diversifying field.

Self-care tooling innovation in a disabled kea (Nestor notabilis)

Tooling is associated with complex cognitive abilities, occurring most regularly in large-brained mammals and birds. Among birds, self-care tooling is seemingly rare in the wild, despite several anecdotal reports of this behaviour in captive parrots. Here, we show that Bruce, a disabled parrot lacking his top mandible, deliberately uses pebbles to preen himself. Evidence for this behaviour comes from five lines of evidence: (i) in over 90% of instances where Bruce picked up a pebble, he then used it to preen; (ii) in 95% of instances where Bruce dropped a pebble, he retrieved this pebble, or replaced it, in order to resume preening; (iii) Bruce selected pebbles of a specific size for preening rather than randomly sampling available pebbles in his environment; (iv) no other kea in his environment used pebbles for preening; and (v) when other individuals did interact with stones, they used stones of different sizes to those Bruce preened with. Our study provides novel and empirical evidence for deliberate self-care tooling in a bird species where tooling is not a species-specific behaviour. It also supports claims that tooling can be innovated based on ecological necessity by species with sufficiently domain-general cognition.

Kea (Nestor notabilis) fail a loose-string connectivity task

Naïve individuals of some bird species can rapidly solve vertical string-pulling tasks with virtually no errors. This has led to various hypotheses being proposed which suggest that birds mentally simulate the effects of their actions on strings. A competing embodied cognition hypothesis proposes that this behaviour is instead modulated by perceptual-motor feedback loops, where feedback of the reward moving closer acts as an internal motivator for functional behaviours, such as pull-stepping. To date, the kea parrot has produced some of the best performances of any bird species at string-pulling tasks. Here, we tested the predictions of the four leading hypotheses for the cognition underpinning bird string-pulling by presenting kea with a horizontal connectivity task where only one of two loose strings was connected to the reward, both before and after receiving perceptual-motor feedback experience. We find that kea fail the connectivity task both before and after perceptual-motor feedback experience, suggesting not only that kea do not mentally simulate their string-pulling actions, but also that perceptual-motor feedback alone is insufficient in eliciting successful performance in the horizontal connectivity task. This suggests a more complex interplay of cognitive factors underlies this iconic example of animal problem-solving.

Individual Goffin´s cockatoos (Cacatua goffiniana) show flexible targeted helping in a tool transfer task

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 experimentally shown in chimpanzees and in Eurasian jays. Recent studies highlight the prosocial tendencies of several bird species, yet flexible targeted helping remained untested, largely due to methodological issues as such tasks are generally designed around tool-use, and very few bird species are capable of tool-use. Here, we tested Goffin's cockatoos, which proved to be skilled tool innovators in captivity, in a tool transfer task in which an actor had access to four different objects/tools and a partner to one of two different apparatuses that each required one of these tools to retrieve a reward. As expected from this species, we recorded playful object transfers across all conditions. Yet, importantly and similar to apes, three out of eight birds transferred the correct tool more often in the test condition than in a condition that also featured an apparatus but no partner. Furthermore, one of these birds transferred that correct tool first more often before transferring any other object in the test condition than in the no-partner condition, while the other two cockatoos were marginally non-significantly more likely to do so. Additionally, there was no difference in the likelihood of the correct tool being transferred first for either of the two apparatuses, suggesting that these birds flexibly adjusted what to transfer based on their partner´s need. Future studies should focus on explanations for the intra-specific variation of this behaviour, and should test other parrots and other large-brained birds to see how this can be generalized across the class and to investigate the evolutionary history of this trait.

Carrion Crows and Azure-Winged Magpies Show No Prosocial Tendencies When Tested in a Token Transfer Paradigm

To study the evolution of humans' cooperative nature, researchers have recently sought comparisons with other species. Studies investigating corvids, for example, showed that carrion crows and azure-winged magpies delivered food to group members when tested in naturalistic or simple experimental paradigms. Here, we investigated whether we could replicate these positive findings when testing the same two species in a token transfer paradigm. After training the birds to exchange tokens with an experimenter for food rewards, we tested whether they would also transfer tokens to other birds, when they did not have the opportunity to exchange the tokens themselves. To control for the effects of motivation, and of social or stimulus enhancement, we tested each individual in three additional control conditions. We witnessed very few attempts and/or successful token transfers, and those few instances did not occur more frequently in the test condition than in the controls, which would suggest that the birds lack prosocial tendencies. Alternatively, we propose that this absence of prosociality may stem from the artificial nature and cognitive complexity of the token transfer task. Consequently, our findings highlight the strong impact of methodology on animals' capability to exhibit prosocial tendencies and stress the importance of comparing multiple experimental paradigms.